Could a test really detect if someone is a COVID-19 ‘superspreader’?


Lara Herrero, Griffith University

Last week we heard Queensland-based biotech company Microbio had developed a test that could, according to media reports, tell whether someone is a COVID-19 superspreader.

While this may sound like an exciting prospect, there are a few questions to answer before we know what role this test might have in managing the spread of COVID-19.

First, what is a superspreader?

It’s important to understand there’s no scientific definition of a “superspreader”.

In the context of COVID-19, the term “superspreader” has been used to describe someone who can spread the virus and cause infection in many people with minimal contact.

There are many factors thought to contribute to what makes someone a superspreader. The most talked about is infectious viral load. Put simply, this is the amount of live infectious virus a person carries.

Current thinking is that people with a higher infectious viral load are more likely to infect others, but it may not be that simple.

An illustration of SARS-CoV-2, the coronavirus that causes COVID-19.
SARS-CoV-2 is the coronavirus that causes COVID-19.
Shutterstock

When a person has a COVID-19 test, the health-care worker uses a swab to collect samples from the back of the person’s nose and throat. These are the areas where the virus likes to live. The swab is then sent to a pathology lab which tests for the presence of viral genomic material.

The test returns as a positive (that is, the virus has been detected) or negative (virus not detected). There’s no indication of how much virus is present, or whether it’s replicating.




Read more:
Coronavirus: superspreading events could help make COVID-19 endemic


So, back to the new test

Microbio says the newly developed InfectID-COVID-19-R test can detect “replication-competent virus”. This essentially means the test would detect the amount of active live virus a person is carrying. Researchers believe the patient is most likely to be infectious when the virus is replicating.

Like current COVID-19 tests, the test requires a sample of viral genetic material from a patient swab. The genetic material is “extracted” from the swab (termed RNA extraction). The resulting sample is put through a machine to detect an important part of the virus genome which indicates whether the virus is alive and replicating.

InfectID-COVID-19-R claims to accurately detect a virus concentration as low as 1,500 TCID50 per millilitre with 99% specificity. (TCID50 stands for tissue culture infectious dose 50% — it’s currently the accepted standard to quantify the amount of infectious SARS-CoV-2.)

This equation may be tricky to grasp, but the important part to understand is that below this threshold, the person has a lower amount of replicating virus than the test can guarantee to detect. They can’t say for certain the person has no replicating virus.

If a person records a result above the threshold, that tells scientists the virus is alive and replicating.

The suggestion is the test will be able to quantify the amount of replicating virus present in the swab. But exactly what that means — and how the test will achieve this — is uncertain.




Read more:
A few superspreaders transmit the majority of coronavirus cases


Microbio’s media release is tight-lipped on a few key aspects of this test. We still don’t have answers to some questions, including:

  • what part of the virus genome it is detecting, and how is this different to our current diagnostic tests?

  • how does detecting this part of the virus ensure detection of replicating or “live” virus?

  • how will the test results be presented? For example, will the test provide a reference range and guide on how to interpret the result?

  • how can they prove that if a test comes back below the limit of detection for replicating virus that the person is not infectious?

In response to queries from The Conversation, Microbio’s chief scientific officer Flavia Huygens said the new test “targets the part of the virus’ genome that is present while it is replicating inside the human cell”, and that this target is different to existing COVID-19 tests. She added: “Our test detects the portion of the virus genome that is only present whilst the virus is replicating and hence is indicative that the virus is “live.”

Huygens also said the test has built-in references and guides for clinical laboratories to interpret the results.

It’s early days yet

Without more detail, it’s too early to tell just how useful this test will be.

Certainly, we need to know whether a low replicating viral load means a person is not infectious before using this test to make any decisions around quarantine. Research is still ongoing in this area.

A lecture theatre full of people.
It may be more accurate to describe ‘superspreading events’.
Shutterstock

The test hasn’t yet been approved for use. It has been independently validated by 360 biolabs, a clinical trial laboratory accredited by the Australian National Association of Testing Authorities. Huygens told The Conversation that Microbio is planning further validation of its test using patient samples.

More than a question of viral load

Currently we have no way to know who may be a superspreader. While this test might give us a measure of a person’s replicating viral load, this is only one piece of the puzzle.

As is the case for any virus, spreading SARS-CoV-2 requires more than just high viral load. It requires the right environmental conditions (for example, indoors and lower humidity), proximity to an infected person, and time (more time exposed means more chance of infection).

Therefore it’s more accurate to refer to “superspreading events” rather than to particular people as “superspreaders” more generally. Superspreading events are situations in which one person, aided by the ideal conditions, infects a large number of others.

With this in mind, limiting the time you spend in confined spaces (and wearing a mask if you can’t avoid a closed space), washing your hands and keeping your distance will be your best protection against COVID-19.




Read more:
Why do some COVID-19 tests come back with a ‘weak positive’, and why does it matter?


The Conversation


Lara Herrero, Research Leader in Virology and Infectious Disease, Griffith University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Infecting volunteers with coronavirus may be one way to test potential vaccines. But there are risks



Shutterstock

Euzebiusz Jamrozik, Monash University; Kanta Subbarao, The Peter Doherty Institute for Infection and Immunity, and Michael Selgelid, Monash University

Researchers are considering using “human challenge studies” to accelerate COVID-19 vaccine research and development. This would involve giving an experimental vaccine to healthy volunteers, then deliberately exposing them to the virus to see whether they’re protected from infection.

Challenge studies can also allow scientists to monitor the progress of infectious diseases from the moment they begin, and to study infection and immunity more closely than other types of research.

These studies can answer scientific questions in a short time. They recruit small numbers of participants — up to around 100 volunteers per study — usually young, healthy adults.

However, deliberate infection with SARS-CoV-2, the virus that causes COVID-19, involves risks to volunteers.

How do these studies differ from standard, larger studies?

Standard “field” trials for some COVID-19 vaccine candidates have already begun. Each aims to recruit at least 10,000 people. Usually, half or two-thirds receive the experimental vaccine and the rest might receive a placebo or a vaccine against another disease.

Participants then go about their daily lives. Scientists observe whether those who received the COVID-19 vaccine are less frequently infected with the virus than the other group, allowing them to determine how effective the vaccine is.

Two scientists in a lab look at a syringe.
Human challenge studies involve fewer participants than standard field trials.
Shutterstock

In large epidemics, field trials can quickly reveal whether a vaccine works. But proof may be delayed when there’s less community transmission, for example due to local public health measures.

If current field trials identify a highly effective vaccine, there might be less need for human challenge trials. However, if the first vaccines fail, or turn out to be only moderately effective, challenge studies could be used to select the next most promising candidates for future field trials.




Read more:
From adenoviruses to RNA: the pros and cons of different COVID vaccine technologies


Challenge studies need extra preparation

First, scientists need to prepare a strain of SARS-CoV-2 in the laboratory to administer to volunteers. The strain needs to be similar to the virus circulating in the community.

There’s also a need for special research facilities with health-care support and capacity to isolate participants.

Volunteers may have to remain in these facilities for 2–3 weeks to be closely monitored, and so they are not released into the community while they may be infectious.




Read more:
Coronavirus: why I support the world’s first COVID vaccine challenge trial


Past experience and recent developments

While COVID-19 challenge trials are now making news, scientists have previously conducted these kinds of experiments with many different types of microorganisms.

Such studies have been used to develop vaccines against malaria, typhoid and cholera. They have also provided unique insights into immunity to influenza and “common cold” coronaviruses.

One research centre in London has announced a plan to conduct challenge studies with SARS-CoV-2. Another centre in the United States is also preparing a strain of the virus.

Ethical and scientific questions

The World Health Organisation (WHO) convened two advisory groups, in which we were involved, to consider COVID-19 human challenge studies. One focused on ethics, the other on scientific and technical aspects.

The ethics group identified eight criteria proposed challenge studies would need to meet before going ahead.

These included the need for researchers to consult and engage with the general public before, during, and after the trials. There would also need to be careful independent expert review, and demonstration that expected benefits are likely to outweigh risks.

Relevant risks might be especially hard to predict for SARS-CoV-2, partly because it’s a new pathogen.

While young, healthy people generally fare better with COVID-19 than older adults with pre-existing conditions, there are exceptions. For example, a multisystem inflammatory syndrome has been reported in rare cases among previously healthy adults after they contracted COVID-19.




Read more:
Infecting healthy people in vaccine research can be ethical and necessary


Members of WHO’s science group agreed on a number of technical requirements for COVID-19 challenge studies to maximise volunteers’ safety and prevent wider spread of infection.

These included recruiting only healthy young adults, conducting the studies under strict biosafety procedures (for example, isolating participants), giving the virus via the nose to mimic natural infection, and carefully increasing the dose of the virus.

Group of young adult students outside looking at books and papers, studying
Only young adults without underlying health conditions could volunteer for these studies.
Shutterstock

However, the experts were split on other issues, such as whether:

  • challenge studies would actually accelerate vaccine approval

  • results in young healthy adults would demonstrate whether or not a vaccine works for older people

  • challenge trials should begin before a proven and highly effective treatment for COVID-19 becomes available.

What next?

To design an ethically acceptable challenge study, it’s important to minimise the risks to study volunteers, research staff, and the wider community.

In the future, there may be additional ways scientists can reduce the risks. They may be able to better identify those at lowest risk of severe infection, develop a weakened strain of the virus, or have a highly effective treatment on hand to use if needed.

In the meantime, scientists could obtain results relevant to COVID-19 by conducting less risky challenge studies with other viruses.

For example, challenge studies with “common cold” coronaviruses, which are being considered in Australia, could teach us about the types of immune responses that protect us against coronavirus diseases.




Read more:
Australia’s just signed up for a shot at 9 COVID-19 vaccines. Here’s what to expect


Research eventuating in safe and effective vaccines for COVID-19 could save many lives. However, whether the benefits of challenge studies in the current pandemic outweigh the risks depends on many factors.

We must carefully consider proposals for these studies in light of the current state of science and vaccine development, and update our evaluations as new data emerge.The Conversation

Euzebiusz Jamrozik, Infectious Disease Ethics Fellow, Ethox & Wellcome Centre for Ethics and Humanities, Univeristy of Oxford. Adjunct, Monash University; Kanta Subbarao, Professor, The Peter Doherty Institute for Infection and Immunity, and Michael Selgelid, Professor of Bioethics, Monash Bioethics Centre, Monash University, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why do some COVID-19 tests come back with a ‘weak positive’, and why does it matter?


Sheena G. Sullivan, WHO Collaborating Centre for Reference and Research on Influenza and Jennifer MacLachlan, The Peter Doherty Institute for Infection and Immunity

When we get a test result for a disease like COVID-19, we naturally expect it to be either positive or negative. But the results of these tests are not so black and white.

Polymerase chain reaction, or “PCR”, is the most common test to detect the presence or absence of SARS-CoV-2, the virus that causes COVID-19.

Recently, a “weak positive” case of COVID-19 was reported in the Northern Territory.

Let’s take a look at why someone might get a weak positive result.

Shouldn’t you just be ‘positive’ or ‘negative’?

PCR tests are used to detect a range of viruses and pathogens. They look for viral genetic material in a respiratory sample, such as a nose or throat swab or a saliva sample.

We identify a sample to be positive or negative based on the number of times we need to amplify the small segments of genetic material to detect the virus — and whether this number falls below or above a certain threshold.

When there’s a lot of virus present, we only need a few cycles of amplification to detect it. When there isn’t much virus, or there’s none, we need to amplify the sample several more times until finally we cross the threshold and deem the sample negative.




Read more:
The new 15-minute test has potential, but standard tests are still the best way to track COVID-19


So in this process we can see the potential for a weak positive result. It would generally be a reading at or just above the threshold. And that threshold varies depending on the test used.

Importantly, thresholds are just the point at which we believe we’ve detected something. They’re not 100% precise. Sometimes results just above or below the threshold might be false negatives or false positives.

When might you have a weak positive result?

In most cases, the genetic material of a virus is only detectable when we’re infected and the virus is still replicating and shedding into our respiratory passages.

But sometimes, even when the virus is no longer alive and replicating, it can hang around and be detectable by PCR. In these cases, it’s unclear whether the virus is infectious.

A health worker dressed in PPE prepares to take a swab from a man in his car.
PCR tests for COVID-19 look for the genetic material of SARS-CoV-2.
Shutterstock

In the case of the NT man, he had earlier tested positive for COVID-19 in Victoria and recovered. Although he recorded a negative test before travelling to the NT, it’s likely he was still just shedding small amounts of the virus.

This may be more common among people with weaker immune systems, as it takes them longer to clear the virus from their system.

How do we handle weak positives?

A weak positive is treated as a “presumptive positive” result — we presume it to be positive, and generally classify it as such, until we have information to suggest otherwise.

National testing guidelines for COVID-19 recommend weak positive results be checked by testing the same sample again. They also recommend collecting another sample.

In some cases, retesting the original sample may give more confidence of an infection with SARS-CoV-2. But collecting and testing another sample can offer further confirmation.

The subsequent test might target a different region of the virus’ genetic material, or use a different type of test. Alternatively, the sample could be referred to a reference laboratory to verify the result using specialised tests.




Read more:
Goodbye, brain scrapers. COVID-19 tests now use gentler nose swabs


We don’t know of any publicly available data which indicate how common weak positive results are. But we don’t think they’re unusual.

It’s one of the reasons the publicly reported case numbers for COVID-19 are sometimes revised downwards, as weak positives are later confirmed to be negative after retesting.

It’s also not unique to COVID-19 or PCR — many different tests, for a variety of diseases, can produce weak positives.

But the phenomenon has a unique impact when the infection is part of a pandemic.

The danger of assumption

During a pandemic, there are implications not just for the person being tested, but for their contacts, their workplace, and the whole population.

Incorrectly assuming a weak positive result isn’t COVID-19 could lead to a person continuing to transmit the disease to others. It could also prevent them receiving the proper monitoring and, if necessary, treatment.

Conversely, assuming a weak positive result is COVID-19 when it’s actually negative could lead to the person being unnecessarily quarantined, which has potential personal, psychological and financial effects.

A man wearing a mask looks out the open window of his home.
A weak positive result which turns out to be negative could see a person isolated unnecessarily.
Shutterstock

In the case in the NT, classifying this indeterminate result as a positive case would have meant the first COVID-19 infection in two months in that state.

While the man was isolated, NT authorities didn’t count him as a case based on advice from the health department that the result was likely due to residual virus from his previous infection. They said he didn’t have any symptoms and it was highly unlikely he was infectious.

When the elimination of community transmission is being used as a criteria for border closures, individual cases can have significant flow-on effects to the whole population.

For these reasons, it’s important to appreciate the complexities of COVID-19 testing. It’s not always as simple as “positive” or “negative”.




Read more:
Worried you might test positive and put a spanner in Victoria’s COVID roadmap? Here’s why you should get tested anyway


The Conversation


Sheena G. Sullivan, Epidemiologist, WHO Collaborating Centre for Reference and Research on Influenza and Jennifer MacLachlan, Epidemiologist, WHO Collaborating Centre for Viral Hepatitis, The Peter Doherty Institute for Infection and Immunity

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Vital Signs: batch testing and contact tracing are the two keys to stop the lockdown yo-yo




Richard Holden, UNSW

Back in March and April I (and many other economists) argued for lockdowns to get COVID-19 infections under control and to give health systems time to put in place testing and tracing regimes to contain the virus in the longer term.

This was done pretty effectively everywhere in Australia except for Victoria. But if things go to plan, all states will be back on the same page by the end of October.

Or will they?

Concerns about Victoria’s contact-tracing regime remain, and although there is a lot of testing, how it is being done might not be as effective as possible.

More still needs to be done to avoid the “yo-yoing” Victorian premier Dan Andrews has warned about – in which relaxation of distancing rules leads to yet another outbreak big enough to require reimposing restrictions.

There is room for not just incremental improvement but dramatic improvement of testing and tracing.

Keeping the reproduction rate below 1

The key to avoiding the need for lockdown (unless and until a vaccine is widely deployed) is to keep what epidemiologist call the “effective” reproduction rate (R) below 1.

That is, on average each person infected with the virus must give it to less than one other person (R<1).

If R>1 infections will grow exponentially, overwhelming human contact-tracing systems and eventually the hospital system.

To keep the reproduction rate below 1 requires testing and contact tracing to be incredibly fast and effective.

Effective contact tracing

Victoria’s contact-tracing system is generally regarded as having performed poorly compared with systems such as in New South Wales.

The clunky system includes notifications of new infections still being sent by fax.

Only now is the state moving to adopt a more automated approach, using a data management system developed by IT giant Salesforce. The Victorian government rejected the system earlier in the year, on the grounds the state was too swamped by the first wave to implement and bed down a new system.

My University of NSW colleague, epidemiologist Raina MacIntyre, has observed that Victoria’s health system was less prepared than NSW because of 20 years of governments “stripping the health system bare”, and that:

No health workforce in the world, no matter how organised, well-resourced and efficient, can do manual contact tracing successfully when an epidemic becomes too large.

We could go down the more aggressive digital contact-tracing path akin to South Korea. But as the Financial Times has noted, the Korean systems:

include an extensive trawl of data from other sources, such as security cameras and credit card transactions, as well as smartphone apps that use wireless signals to detect who might have encountered an infected individual.

Given the relatively low voluntary uptake of the Australian government’s COVIDSafe smartphone tracing app, getting enough people to use it to make it effective will also require strong incentives – or compulsion.

Now, I’m strongly for such incentives (as well as smarter testing). But given the amount of bedwetting about the existing COVIDSafe app from the libertarian right and some elements of the soft left (who are paranoid about every smart light bulb spying on us), this is unlikely to happen.




Read more:
Vital Signs: Modelling tells us the coronavirus app will need a big take-up, economics tells us how to get it


Batch testing

The other crucial tool to keep R below 1 is efficient and large-scale testing.

Australia did well early in the pandemic ramping up testing capacity. Test results have been typically returned within a few days, though there have also been reports of results taking more than five days.



What we have not done is embrace the benefits of targeted batch testing.

Batch testing is a way to cost-effectively test large numbers of people by pooling together samples – say by postcode.

If the pooled sample comes back negative, then everyone who contributed to the batch is cleared. If it is positive, more targeted testing is done, using smaller batches (by suburb, then residential block, then by household).




Read more:
Vital Signs: We’re testing 50,000 Australians a day for COVID-19. Should it be 6.5 million?


As I’ve noted before, the optimal batch size depends on the base rate of the virus in the community. But this general idea has been around since World War II and is well understood. It is a way to stretch resources to test more of the population more often.

For Australia at this point of the pandemic, this kind of testing would enable rapid detection and isolation of any new infections, allowing social and economic activity to get back to a new normal.

The strategy going forward

Once the Victorian outbreak is under control, we need to reopen Australia’s internal borders. Then we can start thinking about easing external border restrictions with places such as New Zealand.

All of this will require keeping the reproduction rate below 1, which means catching any new infections fast. Really fast.

Yo-yoing lockdowns are costly and to be avoided if at all possible.

Automated contact tracing could help a lot, as could smart and aggressive batch testing. We should be doing both until a vaccine is deployed.

Some commentators talk about “living with this virus” which is basically code for letting it rip. Instead, what we need to do is engage in “relentless suppression” to keep the reproduction rate low and our economy open.The Conversation

Richard Holden, Professor of Economics, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Worried you might test positive and put a spanner in Victoria’s COVID roadmap? Here’s why you should get tested anyway


Breanna Wright, Monash University

Victoria’s much-anticipated roadmap out of lockdown was released on Sunday, bringing with it a clear outline of how (and provisionally when) Victoria will see an easing of restrictions.

The plan is transparent about the case numbers, or lack of them, required for the state to move to each progressive stage. For example, moving to the second step, provisionally scheduled for September 28, will require an average of 30-50 new cases per day over a 14-day period.

Victorians are suffering from lockdown fatigue. They’re exhausted and drained. The reopening of playgrounds, the singles bubble, shortening the curfew, and an extra hour of daily exercise are all gestures to keep them going during this difficult time. But many people are still desperate for the lockdown to end.

Lockdown won’t be over until the number of positive cases falls. And there’s a risk that a desire to end restrictions might discourage Victorians from getting tested, for fear of adding to the numbers and prolonging the lockdown.

Not getting tested?

The way society views an illness affects how people who have it or might have it feel and behave. Since the beginning of the pandemic, terms such as “COVID suspect” or “superspreader” have risked creating a sense of shame for those who contract the virus.

Those feeling unwell may not want to be seen as “part of the problem”. We know from other diseases, when there is stigma attached to being sick, people with symptoms are less likely to seek care. No Victorian will want to be blamed for restrictions lasting any longer than they have to.




Read more:
Why children and teens with symptoms should get a COVID-19 test, even if you think it’s ‘just a cough’


Testing is still vital

Nevertheless, it is crucial people continue to get tested. Without this information, it will be impossible for the government to negotiate a safe path out of restrictions. Gaps in our knowledge could mean the decision-makers don’t have enough confidence to progress to the next step.

Analysts already know when there are gaps in our understanding. Earlier this week, evidence of the coronavirus was found in sewage from Apollo Bay, about 200 kilometres southwest of Melbourne, despite no one in the area having tested positive.

Test results are just one piece of data — albeit a crucial one — that informs our understanding of the situation. Testing actually helps us move forward faster, not slower.

How to encourage testing

There are several ways to ensure the number of COVID-19 tests remains high. More than 2,403,388 tests have now been done in Victoria, 12,938 on Sunday.

1. Create a sense of pride in getting tested

Obviously, low numbers of positive tests are good. But high numbers of negative tests are much more informative than no test results at all. Telling your friends you’ve been tested, or posting it on social media, should be a source of pride that you’re doing your bit for Team Victoria.

2. Remove the stigma and shame

We should also work to remove the stigma of contracting COVID-19 — no one is catching it on purpose, after all. Campaigns such as Melbourne Strong aim to help people who are struggling in lockdown, and we should extend this kind of support to those going through COVID-19 itself.

3. Promote positive messaging

It’s important to remember how far we’ve come since the peak of Victoria’s second wave. On July 30 there were 723 new cases; on Monday we had 41. We also now know the targets we need to hit to end the restrictions, and Premier Daniel Andrews has raised the possibility they could even be lifted early. Influential community messengers can help reinforce this message of hope.

4. Make testing easier

The Victorian government has tried to make testing as easy as possible, through measures such as mobile testing, incentive payments and research into faster tests. They should also consider keeping information on wait times for different testing sites up to date, as for many places it is not currently available.




Read more:
Goodbye, brain scrapers. COVID-19 tests now use gentler nose swabs


There’s no easy road out of this pandemic, but now we have the roadmap and we know where we need to get to. So if you have COVID-19 symptoms, don’t hesitate to get tested. You’ll be doing yourself and the whole state a favour.The Conversation

Breanna Wright, Research fellow, BehaviourWorks Australia, Monash Sustainable Development Institute, Monash University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Do I need a referral for a COVID-19 test? What happens if you test positive? Your coronavirus questions answered


Trent Yarwood, The University of Queensland

As COVID-19 cases surge in Victoria and NSW, authorities have again urged anyone with symptoms, including cough, fever, or sore throat, to get tested. Most results should be available within a few days and people should self-isolate while they’re awaiting results.

Victorian Premier Daniel Andrews said today Victoria recorded 275 new COVID-19 cases. Mask-wearing whenever outside the home will be mandatory for residents of metropolitan Melbourne and Mitchell Shire from Wednesday at 11:59pm.

NSW Premier Gladys Berejiklian said there were 20 new cases in NSW today, and urged residents to avoid crowded places, consider wearing a mask when physical distancing wasn’t possible, and minimise any non-essential travel.

Here are the most important things to know about testing.




Read more:
Got a COVID-19 test in Victoria and still haven’t got your results? Here’s what may be happening — and what to do


Do I need a referral to get a COVID-19 test?

For the vast majority of people, no — you don’t need a referral to get tested at dedicated public COVID-19 testing clinic.

However, you will need a pathology request form if you plan to get tested at a private pathology clinic.

COVID-19-testing clinics in NSW are listed here, and Victorian testing sites (including pop-up clinics) are listed here. The Victorian Department of Health and Human Services says on it website:

Please call ahead before visiting a testing site, unless you choose to be tested at a pop-up testing site.

Testing locations are listed on each state or territory’s health departments, including for Queensland, Western Australia, South Australia, Northern Territory and the Australian Capital Territory.

Start by seeing if there is a pop-up drive-through or walk-through clinic near you. Some public sector fever clinics have a booking system to reduce wait times but many of the pop-up testing drive-through sites will allow you just to show up in your car.

Do not walk unannounced into a private pathology clinic, hospital emergency department or into your GP’s surgery.

If you can’t get to a dedicated public COVID-19 testing clinic, call your GP and ask for a telehealth consult. The GP can organise a pathology request form to be sent electronically to a private pathology clinic and will advise you on how to get tested there.

While you’re waiting for your test results, it’s important to stay at home in case you are infectious.




Read more:
Explainer: what’s the new coronavirus saliva test, and how does it work?


What happens if I test positive?

You will be notified if you’ve tested positive to COVID-19. If you were tested at a private clinic, you may receive a call from your GP who ordered the test, or from the public health team.

If you were tested at a public testing site like a drive-through clinic, a state government public health official will contact you. They will usually do the contact tracing at the same time.

Their job is to find out about anyone else you may have given the virus to while you’ve been infectious. They will usually ask where you’ve been and who you’ve seen in the last few days before you became ill.

There are national guidelines for management of coronavirus, but how they are implement is usually a state decision. Generally, the facility where you got the test will tell you how long you need to isolate for.

It’s important to ask as many questions as possible when you’re informed of your result.


The Conversation, CC BY-ND

How can I get tested? Is there a blood test?

Most tests will usually be done by a swab around the back of the throat and the nose. Some sites will either just swab your throat, or just your nose, but the gold standard at the moment is to swab both.

There’s also a new saliva test, which tests a sample you spit into a small container. It’s used in limited circumstances where it’s not possible to take a nasal swab, such as with young children resisting a swab.

The problem is saliva seems to have less of the virus in it than sputum (which is collected from the back of the nose and throat), so a saliva test result may not be as reliable.

There are currently two types of blood tests. One is an antibody test, which can measure whether you’ve already had the virus and recovered. But it’s not very useful because health authorities are more concerned about finding out who has the virus now, so they can do contact tracing.

Researchers from Monash University announced recently they’ve able to detect positive COVID-19 cases using blood samples in about 20 minutes, and identify whether someone has contracted the virus.

However, it’s very new research and likely won’t be rolled out on a large scale very soon. The researchers said last week they’re seeking commercial and government support to upscale production.

Despite problems with new types of tests, in a pandemic it’s important to research and trial novel testing methods that can help us fight the virus.

The most important thing you can do to help stop the spread is to try to maintain physical distancing as much as you can. Wash your hands frequently, and if you develop any symptoms — even very minor ones — err on the side of getting tested.




Read more:
Which face mask should I wear?


The Conversation


Trent Yarwood, Infectious Diseases Physician, Senior Lecturer, James Cook University and, The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Got a COVID-19 test in Victoria and still haven’t got your results? Here’s what may be happening — and what to do


Hassan Vally, La Trobe University

Stories are emerging of Victorians who have followed advice and sought a COVID-19 test, only to find they’re still waiting to hear results more than five days later.

The scale of testing underway in Victoria — and Australia’s testing rates are among the highest in the world — means it’s likely this will happen from time to time. It’s unclear if this is happening to many people or to just a handful.

Nevertheless, it’s evidently happening to some people and we can piece together some information about what may be contributing to this problem, and what you can do if it happens to you.




Read more:
Eradication, elimination, suppression: let’s understand what they mean before debating Australia’s course


What to do if it happens to you in Victoria

Firstly, if you are showing symptoms and still waiting on results of a test, it’s important you do not go out. Of course, that will grow increasingly difficult the longer you wait for a test result but self-isolating while awaiting test results is a crucial part of the pandemic management strategy.

Victorian health minister Jenny Mikakos said on Twitter results are usually available within 1-3 days or “sometimes longer” and referred people to a health department fact sheet.

The factsheet says:

Victorian and interstate labs are working around the clock to process all the tests, but with so many coming in every day, sometimes it takes a little longer to confirm the results.

It lists phone numbers to try if you haven’t got your result within the expected time frame.

Information from a Victorian health department factsheet.
DHHS

The factsheet doesn’t say what to do if you did the test using a home testing kit but the Victorian Department of Health and Human Services later tweeted to say:

Of course, if all else fails it might be simplest just to go and get another test.




Read more:
Australia’s coronavirus testing rates are some of the best in the world – compare our stats using this interactive


Why might this be happening?

Again, we must acknowledge the enormous scale of the testing program underway in Victoria.

On Wednesday alone, 28,607 tests were undertaken in Victoria, and the total number of tests undertaken since January 1 is now at 1,225,999, Victorian Premier Daniel Andrews said in his Thursday press briefing.

Widespread testing is one of the best things we can do to control the spread of coronavirus, and these numbers are very impressive.

Many of these tests will be processed at laboratories in other states, as it is not possible for Victorian labs to test so many samples on their own.

A health department factsheet dated June 25, 2020 said:

Laboratories in Victoria, with surge staff capacity, can process 18,000 tests a day, noting that turn-around times are adversely affected when there is sustained testing above 14,000 tests per day.

New South Wales, South Australia, Queensland and Tasmania have agreed to provide surge lab capacity of over 4,000 tests a day. Private laboratories can also provide surge capacity of around 13,500 tests a day through their interstate operations. This will allow for at least 25,000 Victorian tests to be processed a day. There are currently sufficient test kits to meet this level of demand.

In addition, private pathology providers can draw on interstate supply chains. Safeguards, including repeat testing, will manage the risk of false positive tests.

So if you’ve got a test but haven’t heard back, it’s possible the delay is caused by test samples needing to be taken to interstate labs (which adds time) and the huge scale of testing underway.

It’s also possible there may have been some other problem with the test, so make sure you double check at the testing centre.

Who should get tested and why testing is important?

The Victorian health department says on its website:

Testing is currently available for people with the following symptoms, however mild: fever, chills or sweats, cough, sore throat, shortness of breath, runny nose, and loss of sense of smell or taste. The test takes around a minute and involves a swab from the back of your throat and nose.

The less invasive saliva test may also be available for some people in certain places and circumstances, the department has said.

Despite any difficulties you may be experiencing in getting tested or in getting your results, it’s vital to understand how critical getting tested is to protecting the community from this coronavirus. By being tested you are helping limit the spread of COVID-19. You are potentially helping save lives. The Conversation

Hassan Vally, Associate Professor, La Trobe University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why children and teens with symptoms should get a COVID-19 test, even if you think it’s ‘just a cough’


Christopher Blyth, University of Western Australia

A Victorian teenager holidaying on the NSW South Coast has been diagnosed with COVID-19, NSW chief health officer Kerry Chant said on Wednesday.

The revelation follows reports senior students at Al-Taqwa College in Melbourne are now considered the main source of Victoria’s second-biggest COVID-19 cluster.

These cases serve as a reminder that although children and teens are considered less likely than adults to catch and spread COVID-19, everyone with symptoms should get a test — including children and teens.

Children, teens and COVID-19 risk: what we know so far

In my field, paediatric infectious disease, new research is emerging all the time about how SARS-CoV-2 (the virus that causes COVID-19) affects children and teens. In short, the evidence so far says:

  • children and teens can contract and spread the disease — but compared to adults, several studies suggest that they are less likely to.

  • children and teens are much less likely to get severely unwell, be hospitalised or die compared to adults and older people.

  • tragically, children and babies overseas have died of COVID-19, but compared with adults, this is much less common. Thankfully, it has not yet occurred in Australia.

The current thinking is that for most of Australia, the benefit of keeping schools open outweighs the risk. (In metropolitan Melbourne and Mitchell Shire, however, school holidays have been extended for all students except for those in year 11 and 12 or specialist schools.)

In Australia, the youngest COVID-19 death has been a person in their 40s. Less than 7% of all cases in Australia have so far have been recorded in children and teenagers. This proportion may rise, depending on the demographics in areas where community transmission is occurring.

What about older teens?

The risk of becoming unwell with COVID-19 increases with age. We know older teens are very different to young teens, both in growth and development but also in their activities – many of these activities put older teens at greater risk.

As Victoria’s Chief Health Officer Brett Sutton has said

They are older kids, they tend to have more transmission that is akin to adults if they’re not doing the physical distancing appropriately.

And if teens do develop COVID-19, the disease can move incredibly quickly from person to person and may soon reach populations with much greater risk, such as older people.

That’s why the very best strategy we have is to get tested.

Most children or teens with COVID-19, and indeed most people, will experience a mild illness that improves by itself. However, a small proportion of the community will become severely unwell. I’d be encouraging parents to remember that having a test is not just about the child; it’s about the community, children, parents and grandparents.

Most children or teens, and indeed most people, who get COVID-19 will experience a mild illness that improves by itself.
Shutterstock

Younger kids and the constant runny nose or cough

As we head into winter time, we’re starting see more children and adults with common cough and cold viruses. For many parents of younger children, runny noses and coughs are a constant part of life during this time.

To these parents I would say: if it is a new cough, a new fever or sore throat, consider getting the child tested. This is particularly important for those living in places where community transmission is occurring, such as Victoria.

Some children, particularly through winter, will have an ongoing sniffle or cough and one infection will roll into the next. In this situation, the thing to watch for is a worsening of a fever or cough. If this happens, do not hesitate to get tested.


The Conversation, CC BY-ND

Testing is a key strategy

To sum it up, testing is one of the key strategies to contain the spread of COVID-19 in Australia. One needs only look to Victoria to see what can happen when flare-ups occur. Although some of the public health interventions may appear draconian, we have to make sure people who are infectious are separated from those who are susceptible.

If your child is showing symptoms, you might be tempted to think “it’s just a cough” — and most of the time it will be just a cough. It’s not that we think every child with a cough has got coronavirus, but early detection — along with other measures such as physical distancing, staying home if unwell and hand hygiene — is absolutely crucial in our response.The Conversation

Christopher Blyth, Paediatrician, Infectious Diseases Physician and Clinical Microbiologist, University of Western Australia

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Why some people don’t want to take a COVID-19 test


Jane Williams, University of Sydney and Bridget Haire, UNSW

Last week, outgoing chief medical officer Brendan Murphy announced all returned travellers would be tested for COVID-19 before and after quarantine.

Some were surprised testing was not already required. Others were outraged some 30% of returned travellers in hotel quarantine in Victoria had declined to be tested.

This week, Victorian premier Daniel Andrews said more than 900 people in two Melbourne “hotspots” had declined door-to-door testing.

Again, there was outrage. People refusing COVID-19 tests were labelled selfish and rude.

A positive test result, together with contact tracing, gives public health authorities important information about the spread of SARS-CoV-2, the coronavirus that causes COVID-19, in a community.

So why might people at higher risk of a positive result be reluctant testers? And what can we do to improve testing rates?

The many reasons why

Reluctance to be tested for COVID-19 is not unique to returned travellers in hotel quarantine or people living in “hotspot” suburbs.

In the week ending June 28, FluTracking, a voluntary online surveillance system, reported only 46% of people with a fever and cough had gone for a COVID-19 test.

That can be for a variety of reasons.

A medical test result is not a neutral piece of information. People may refuse medical testing (if they have symptoms) or screening (if no symptoms) of any type because they want to avoid the consequences of a positive result.

Alternatively, they might want to avoid the perceived burden of the test procedure itself.

Reasons may relate to potentially losing money or work

Many reasons for avoiding testing are likely to be structural: a casualised workforce means fewer workers with sick leave and a higher burden associated with having to isolate while waiting for test results. After a COVID-19 test in NSW, for instance, this can take 24-72 hours.

Then there’s the issue of precarious work. If people can’t attend work, either waiting at home for test results or recovering from sickness, they may lose their job altogether.




Read more:
If we want workers to stay home when sick, we need paid leave for casuals


In the case of hotel quarantine, a positive result on day ten will mean a longer stay in isolation. Hotel quarantine is not an easy experience for many, particularly if quarantining alone.

An extension of time at a point where the end is in sight may be a very difficult proposition to stomach, such that avoiding testing is a preferable option.

Another structural issue is whether governments have done enough to reach linguistically diverse communities with public health advice, which Victoria’s chief health officer Brett Sutton recently admitted may be an issue.

Through no fault of their own, may people who don’t speak English as a first language, in Victoria or elsewhere, may not be getting COVID-19 health advice about symptoms, isolation or testing many of us take for granted.




Read more:
Multilingual Australia is missing out on vital COVID-19 information. No wonder local councils and businesses are stepping in


People might fear the procedure or live with past traumas

Reasons may be personal and include fear of the test procedure itself (or fear it will hurt their children), distrust in government or public health systems, and worry about the extent of public health department scrutiny a positive result will bring.

People may also feel unprepared and cautious in the case of door-knocking testing campaigns.

We can’t dismiss these concerns as paranoid. Fears of invasive procedures are associated with past trauma, such as sexual abuse.

People who have experienced discrimination and marginalisation may also be less likely to trust governments and health systems.

COVID-19 can also lead to social stigma, including blame and ostracism, even after recovery.

As with any health-related decision, people usually consider, consciously or not, whether benefits outweigh harms. If the benefit of a test is assumed to be low, particularly if symptoms are light or absent, the balance may tip to harms related to discomfort, lost income or diminished freedoms.

Should we force people to get tested?

Although federal and state laws can compel certain people to undergo testing under limited circumstances, acting chief medical officer Paul Kelly said it was “a last resort”.

Forcing a person to undergo a test contravenes that person’s right to bodily integrity. This is the right to make decisions about what happens to your own body, without outside coercion.

It also involves medical personnel having to override their professional responsibility to obtain voluntary and informed consent.

Some states have indicated they will introduce punishments for refusing testing. They include an extension of hotel quarantine and the potential for fines for people not willing to participate in community testing.




Read more:
Lockdown returns: how far can coronavirus measures go before they infringe on human rights?


Forced testing will backfire

We don’t think forced testing is the way to go. A heavy-handed approach can create an antagonistic and mistrustful relationship with public health institutions.

The current situation is not the only infectious disease emergency we will face. Removing barriers to participating in public health activities, in the immediate and long term, will enable people to comply with and help build trusted institutions. This is likely to create an enduring public good.

Victoria is trying to make testing easier. It is offering a test that takes a saliva sample rather than a nasal swab, which is widely perceived to be unpleasant.




Read more:
Explainer: what’s the new coronavirus saliva test, and how does it work?


This may encourage parents to have their children tested. The test is less sensitive, however, so the gains in increased uptake may be lost in a larger number of false negatives (people who have the virus but test negative).

Ultimately, we need to understand why people refuse testing, and to refine public health approaches to testing that support individuals to make decisions in the public interest.The Conversation

Jane Williams, Researcher at the Centre for Values, Ethics and the Law in Medicine (VELiM), University of Sydney and Bridget Haire, Postdoctoral Research Fellow, Kirby Institute, UNSW

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Explainer: what’s the new coronavirus saliva test, and how does it work?


Deborah Williamson, The Peter Doherty Institute for Infection and Immunity; Allen Cheng, Monash University, and Sharon Lewin, The Peter Doherty Institute for Infection and Immunity

A cornerstone of containing the COVID-19 pandemic is widespread testing to identify cases and prevent new outbreaks emerging. This strategy is known as “test, trace and isolate”.

The standard test so far has been the swab test, in which a swab goes up your nose and to the back of your throat.

But an alternative method of specimen collection, using saliva, is being evaluated in Victoria and other parts of the world. It may have some benefits, even though it’s not as accurate.




Read more:
Victoria is on the precipice of an uncontrolled coronavirus outbreak. Will the new measures work?


Saliva testing can reduce risks for health workers

The gold standard for detecting SARS-CoV-2 (the coronavirus that causes COVID-19) is a polymerase chain reaction (PCR). This tests for the genetic material of the virus, and is performed most commonly on a swab taken from the nose and throat, or from sputum (mucus from the lungs) in unwell patients.

In Australia, more than 2.5 million of these tests have been carried out since the start of the pandemic, contributing significantly to the control of the virus.

Although a nasal and throat swab is the preferred specimen for detecting the virus, PCR testing on saliva has recently been suggested as an alternative method. Several studies demonstrate the feasibility of this approach, including one conducted at the Doherty Institute (where the lead author of this article works). It used the existing PCR test, but examined saliva instead of nasal samples.




Read more:
Keep your nose out of it: why saliva tests could offer a better alternative to nasal COVID-19 swabs


The use of saliva has several advantages:

  • it is easier and less uncomfortable to take saliva than a swab

  • it may reduce the risk to health-care workers if they do not need to collect the sample

  • it reduces the consumption of personal protective equipment (PPE) and swabs. This is particularly important in settings where these might be in short supply.

But it’s not as sensitive

However, a recent meta-analysis (not yet peer-reviewed) has shown detection from saliva is less sensitive than a nasal swab, with a lower concentration of virus in saliva compared to swabs. It’s important to remember, though, this data is preliminary and must be treated with caution.

Nonetheless, this means saliva testing is likely to miss some cases of COVID-19. This was also shown in our recent study, which compared saliva and nasal swabs in more than 600 adults presenting to a COVID-19 screening clinic.

Of 39 people who tested positive via nasal swab, 87% were positive on saliva. The amount of virus was less in saliva than in the nasal swab. This most likely explains why testing saliva missed the virus in the other 13% of cases.

The laboratory test itself is the same as the PCR tests conducted on nasal swabs, just using saliva as an alternative specimen type. However, Australian laboratories operate under strict quality frameworks. To use saliva as a diagnostic specimen, each laboratory must verify saliva specimens are acceptably accurate when compared to swabs. This is done by testing a bank of known positive and negative saliva specimens and comparing the results with swabs taken from the same patients.

When could saliva testing be used?

In theory, there are several settings where saliva testing could play a role in the diagnosis of COVID-19. These may include:

  • places with limited staff to collect swabs or where high numbers of tests are required

  • settings where swabs and PPE may be in critically short supply

  • some children and other people for whom a nasal swab is difficult.

The use of saliva testing at a population level has not been done anywhere in the world. However, a pilot study is under way in the United Kingdom to test 14,000 health workers. The US Food and Drug Administration recently issued an emergency approval for a diagnostic test that involves home-collected saliva samples.

In Australia, the Victorian government is also piloting the collection of saliva in limited circumstances, alongside traditional swabbing approaches. This is to evaluate whether saliva collection is a useful approach to further expanding the considerable swab-based community testing occurring in response to the current outbreaks in Melbourne.




Read more:
These 10 postcodes are back in Stage 3 coronavirus lockdown. Here’s what that means


A saliva test may be better than no test at all

Undoubtedly, saliva testing is less sensitive than a nasal swab for COVID-19 detection. But in the midst of a public health crisis, there is a strong argument that, in some instances, a test with moderately reduced sensitivity is better than no test at all.

The use of laboratory testing in these huge volumes as a public health strategy has not been tried for previous infectious diseases outbreaks. This has required a scaling up of laboratory capacity far beyond its usual purpose of diagnosing infection for clinical care. In the current absence of a vaccine, widespread testing for COVID-19 is likely to occur for the foreseeable future, with periods of intense testing required to respond to local outbreaks that will inevitably arise.

In addition to swab-free specimens like saliva, testing innovations include self-collected swabs (which has also been tested in Australia), and the use of batch testing of specimens. These approaches could complement established testing methods and may provide additional back-up for population-level screening to ensure testing is readily available to all who need it.


This article is supported by the Judith Neilson Institute for Journalism and Ideas.The Conversation

Deborah Williamson, Professor of Microbiology, The Peter Doherty Institute for Infection and Immunity; Allen Cheng, Professor in Infectious Diseases Epidemiology, Monash University, and Sharon Lewin, Director, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne and Royal Melbourne Hospital and Consultant Physician, Department of Infectious Diseases, Alfred Hospital and Monash University, The Peter Doherty Institute for Infection and Immunity

This article is republished from The Conversation under a Creative Commons license. Read the original article.