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.

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



Shutterstock

Craig Lockwood and Lucy Crawford

Early COVID-19 images of swabbing from Wuhan, China, looked more like an Ebola news story — health-care workers fully encased in personal protective equipment (PPE), inserting swabs so deeply that brain injury seemed imminent.

As COVID-19 (and testing) spread around the world, there were reports of “brain scraping”, “brain stabbing” or “brain tickling” swabs. Perhaps this was your experience early in the pandemic. Perhaps these stories have put you off getting tested so far.

But if you go to a drive-through clinic today, you’re likely to have a different swab, one that’s briefly inserted and not so far up as before.

So if fear of the swab itself is holding you back from getting tested, here’s what you need to know about these gentler swabs.

‘Brain scrapers’ not used so much in drive-through clinics

The swabs that gave COVID-19 testing its reputation are the nasopharyngeal swabs. Although these are considered the “gold standard” of testing, they are undeniably uncomfortable.

You remove your mask and blow your nose to clear your nasal passages. Then you try not to sneeze, cough or gag while a health worker inserts a long, flexible shaft about 12cm up your nose and into the back of your throat (until there’s resistance). They then swivel the swab against the back of your throat.

The distance for insertion is significant. Close your eyes and imagine a thin shaft being inserted the length of the space between your nostrils and the outer opening of the ear. The health worker needs to rotate the swab to maximise contact with the contents in the back of the nose before removing it.

The swab may cause your eyes to water, a reflex cough or sneeze. Because of this risk, staff must wear full PPE to avoid risk of being exposed to and inhaling infectious particles and aerosols.

This type of swab is still used in some clinics, and different jurisdictions around the world have different testing policies.




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


You’ll be pleased to hear, things changed

As the pandemic evolved, so have methods of testing, with evidence accumulating about how well they work.

For instance, some Australians have had their saliva tested, including Victorians towards the start of the state’s second wave.




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


But more widely used now in a typical drive-through clinic are a combined swab of the throat and nose.

You’ll be pleased to know the health worker swabs your throat first before using the same swab up your nose (and not the other way around)! This is the so-called oropharyngeal/nasal swab.

First the health worker will use a tongue depressor to keep your tongue down, then swab the area behind and next to the tonsils. Then they will take a nose swab.

If they take a superficial nose swab, they will ask you to look straight ahead before gently inserting the swab upwards until there’s some resistance. Then they will hold the swab in place for 10-15 seconds while rotating it, before repeating this in the other nostril.

If they take a mid-turbinate nasal (also known as a deep nasal) swab, you will tilt your head back slightly. The health worker will then insert the swab horizontally (instead of vertically) until there’s resistance (about two to three centimetres). They will then gently rotate the swab for 10-15 seconds before repeating on the other side.

Why did the swabs change?

If someone is going to stick a swab stick up our collective noses, the test needs to be accurate and reliable.

But what if other options were almost as good, without so much invasion, coughing and increased exposure risk for health-care workers?

So from late March and into April, organisations including the US Food and Drug Administration and US Centers for Disease Control, and Australia’s Public Health Laboratory Network,
announced they would move away from the deeper nasopharyngeal swabs to using nasal swabs for this type of testing.

The recommendation in Australia is to use a combined throat/deep nasal swab but if the health worker thinks it necessary, a nasopharyngeal swab.

Since then, studies suggest the gap between absolute best (nasopharyngeal) and avoiding a gag or cough-inducing reflex (nasal) might not matter as much as once thought.

Comparative studies show throat/nasal swabs are as sensitive as nasopharyngeal to detect SARS-CoV-2, the virus that causes COVID-19.

Other studies show throat/nasal swabs are practical, cheap, accurate and reliable.

Still not convinced? Your brain really is safe

The accumulating evidence suggests the newer nasal swabs are safe, reliable, cheaper to complete, and less unpleasant. They also save expensive, higher grade PPE for where it is needed — in our health-care facilities.

So with testing rates down in Victoria and calls for more testing in New South Wales, this is a reminder we must continue to test, test, test, as well as practise hand hygiene, social distancing, and wearing masks.




Read more:
13 insider tips on how to wear a mask without your glasses fogging up, getting short of breath or your ears hurting


The Conversation


Craig Lockwood, Associate Professor Implementation Science, JBI and Lucy Crawford, Clinical Lecturer

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

Making coronavirus testing easy, accurate and fast is critical to ending the pandemic – the US response is falling far short



There are functional tests for coronavirus, but not enough of them are being done.
AP Photo/Paul Sancya

Zoë McLaren, University of Maryland, Baltimore County

For many people in the U.S., getting tested for COVID-19 is a struggle. In Arizona, testing sites have seen lines of hundreds of cars stretching over a mile. In Texas and Florida, some people were waiting for five hours for free testing.

The inconvenience of these long waits alone discourages many people from getting tested. With the surge in cases, many public testing sites have been reaching maximum capacity within hours of opening, leaving many people unable to get tested for days. Those that do get tested often face a week-long wait to get their test results.

Every person who isn’t tested could be spreading COVID-19 unknowingly. These overstretched testing programs are a weak link in the U.S. pandemic response.

I study public health policy to combat infectious disease epidemics. The key to overcoming this pandemic is to slow transmission of the virus by preventing contagious people from infecting others. A widespread quarantine would accomplish this, but is economically and socially burdensome. Testing offers a way to identify contagious people so they can be isolated to prevent the spread of the disease. This is especially important for COVID-19 because an estimated 40% or more of all people infected with SARS-CoV-2 have few or no symptoms so testing is the only way to identify them.

Some states are doing much better than others. But as a whole, the U.S. is falling far short of the amount of testing needed to control the pandemic. What are the challenges the U.S. is facing? And what is the way forward?

A lab technician using a swab to put a sample into a rapid test machine.
Currently, rapid tests that take about 15 minutes to process are a quick and easy way to diagnose COVID-19 infections, but there are concerns about accuracy.
AP Photo/Carlos Osorio

Testing should be free, easy, fast and accurate

The ultimate goal of testing is for everyone, regardless of symptoms, to know at all times whether they are infected with the coronavirus. To achieve this level of testing, tests should be free, very easy to perform and provide accurate results quickly.

Ideally, free COVID-19 tests would be delivered to everyone directly. The tests would be simple to perform – like a saliva test – and would give a perfectly accurate result within minutes. Everyone could test themselves weekly or anytime they were going to be in close contact with other people.

In this ideal scenario, most, if not all, contagious people would be detected before they could spread the virus to others. And because of the rapid results, there would be no burden of quarantining between doing the test and getting the result.

Researchers are working on better-quality tests, but access is a problem of infrastructure, not science. Right now, nowhere in the U.S. comes close to meeting surging demand for testing.

A line of people waiting in cars in front of a sign for COVID-19 testing.
Long lines, slow turnaround times for results and shortages of testing capacity all make Texas one of the worst places to get a test in the U.S.
AP Photo/David J. Phillip

One of the worst cases: Texas

The difficulty of getting a COVID-19 test varies by state, but currently, people in Texas face some of the biggest obstacles, which results in far fewer tests being done than is needed to control the pandemic.

First, Houston – which is experiencing a surge in cases – and many testing sites across the state recommend or offer testing only to people who have symptoms, were exposed to a COVID-19 case or are a member of a high-risk group.

Even people recommended for testing still face challenges. It is possible to request an appointment for a free COVID-19 test, but testing facilities can handle only so many patients a day and testing slots fill up quickly. Even if someone gets an appointment, they may face an hours-long wait at the testing site.

Finally, public health experts recommend that people who may have been exposed to COVID-19 should quarantine at home for 14 days or until they receive a negative test result. In Texas, patients are supposed to get results through an online portal in three to five days, but many labs have been taking seven to nine days to return results. These long delays mean people face a much higher burden of quarantining while waiting for results.

All of these challenges make it clear that Texas is simply not testing enough people to keep the spread of COVID-19 in check.

To gauge the success of COVID-19 testing programs, epidemiologists use a measure called test positivity. This is simply the percentage of tests that come back positive. The lower the test positivity, the better, because that means very few cases are going undetected. A high test-positivity rate is usually a sign that only the sickest people are getting tested and many cases are being missed.

The World Health Organization guidelines say that if more than 1 out of 20 COVID-19 tests comes back positive – a test positivity of more than 5% – this is an indication that a lot of cases are not diagnosed and the epidemic is not under control. Texas currently has a test-positivity of around 16%, which means that a lot of infected people are not getting tested and may be unknowingly spreading the disease.

A doctor using a nasal swab to test a state senator of New Mexico.
In New Mexico, it is relatively easy to get a test, so more people are getting tested.
AP Photo/Cedar Attanasio

One of the best cases: New Mexico

In stark contrast to Texas is New Mexico, which has one of the strongest testing programs in the U.S.

First, public health officials there encourage everyone to get tested for COVID-19 regardless of symptoms or exposure. The state has also prohibited health providers from charging patients for tests. People seeking a test have the option to walk in or to make an appointment ahead of time, whichever is more convenient.

All of this relatively good access to testing has resulted in one of the highest per capita testing rates in the country, at over 20,000 tests per 100,000 people, and a test-positivity rate of around 4%. New Mexico’s testing program is diagnosing a relatively high proportion of cases despite the state experiencing a recent surge.

[Expertise in your inbox. Sign up for The Conversation’s newsletter and get expert takes on today’s news, every day.]

New Mexico still has room for improvement. Long lines, wait times and limited capacity are becoming more common as cases surge, but the foundation of a strong testing program has helped the state cope with the increase in cases.

The big-picture problems

The pre-pandemic infectious disease testing capabilities in the U.S. are clearly unable to meet the current demand. A nationwide response is needed, and there are three things that Congress, the federal government and local governments can do to help ensure COVID-19 tests will be easy to get, fast and accurate.

First, Congress can provide funding to stimulate the testing supply chain, scale up existing testing programs and promote innovation in test development. Second, governments can improve the management and coordination of testing programs to more efficiently use existing resources. And third, innovative testing methods that reduce the need for lab capacity – like paper-strip tests and pooled testing – need be approved and implemented more quickly.

Every little improvement in testing capabilities means more COVID-19 cases can be caught before the virus is transmitted. And slowing the spread of the virus is the key to overcoming the pandemic.The Conversation

Zoë McLaren, Associate Professor of Public Policy, University of Maryland, Baltimore County

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

Victoria hits bleak record of 484 new cases, NSW at a critical point — if you feel sick, get tested then stay home


Hassan Vally, La Trobe University

Too many people are going out while experiencing COVID-19 symptoms or while awaiting test results, Victorian Premier Daniel Andrews said on Wednesday, after the state hit a bleak new record of 484 new cases. The state’s previous worst daily case number was 428 last Friday.

It’s always a shock to see a new record number, and certainly these numbers are bigger than we would have hoped. While it’s a psychological blow, it’s not cause for panic. Thankfully, we are not seeing a doubling or tripling of case numbers, which really would ring alarm bells.




Read more:
A $200 fine for not wearing a mask is fair, as long as free masks go to those in need


Too many people going out while sick

Andrews chastised people for taking too long to get tested after first experiencing symptoms, which include fever, cough and sore throat. He said:

From 3,810 cases, which are the cases between July 7 and July 21, I’m very unhappy and very sad to have to report that nearly nine in ten – or 3,400 cases – did not isolate between when they first felt sick and when they went to get a test […]

That means people have felt unwell and just gone about their business. They have gone out shopping, they have gone to work, they have been at the height of their infectivity and they have just continued on as usual […] The one and only thing that you can and must do when you feel sick is to go and get tested. Nothing else is acceptable.“

He also said 53% those 3,810 cases “did not isolate, that is, did not stay at home and have no contact with anybody else — between when they had their test taken and when they got the results of that test.”

Unless people stay home when unwell and isolate while awaiting test results, the case numbers will continue to climb, Andrews said.

The premier noted self-isolation would leave some people with no income, and urged people in that situation to call 1800 675 398 to apply for an emergency A$1500 payment.

It’s good to see the premier acknowledge income as one of the major drivers for these behaviours; people may not always have the financial flexibility to do the right thing.

Hopefully, making more people aware of the emergency payment option will help counteract this.

The government may have to work harder to ensure people know to self-isolate, and that the emergency payment is available, and I suspect this will be promoted more widely.

NSW at a critical point

In New South Wales, Premier Gladys Berejiklian said there were 16 new cases in the 24 hours to 8pm last night, all traced to known clusters. She called on people to avoid crowded places, wash hands, stay home if unwell and get tested if they have even mild symptoms.

Berejiklian said from Friday, NSW businesses breaking rules on COVID-Safe registration, and breaching caps on group bookings, would “be fined — worse than that, if you breach again you will be shut down”.

NSW is on especially high alert. Despite this, it’s somewhat reassuring to know the state’s new cases can be traced to known outbreaks. However NSW residents are not out of the woods yet.

Speculation is rife that further lockdowns might be on the way in NSW. While nothing should be off the table, it doesn’t appear NSW is anywhere near this point yet. The state has more than enough capacity to bring things under control from where the numbers sit now.




Read more:
Vaccine progress report: the projects bidding to win the race for a COVID-19 vaccine


Today’s news serves as a grim reminder we must all follow the golden rules of pandemic management: get tested if you experience even mild symptoms, stay home if unwell or awaiting test results, wash your hands often, physically distance from others, limit social gatherings, and wear a mask if you can’t physically distance (face-coverings will be mandatory for residents of metropolitan Melbourne and Mitchell Shire as of midnight Wednesday).

As to where things move from here, much of that is in our hands as individuals. Each of us, by doing everything we can to prevent the spread of the virus, can make a massive contribution to saving lives and defeating COVID-19.

The silver lining is that we know what’s needed. What we’re being asked to do is not easy, but we do know how to bring this coronavirus pandemic under control. We’ve done it before and we can do it again.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.

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.

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


Richard Holden, UNSW

As Victoria grapples with a second-wave outbreak of COVID-19, the importance of large-scale testing has again been highlighted.

Without its “testing blitz” aiming at 10,000 tests a day, the extent of the outbreak would have been invisible for much longer.




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


Australia-wide, we’ve so far achieved a seven-day rolling average of a little more than 50,000 tests a day.



Since the beginning of the pandemic, proponents of mass testing having been arguing the need to test dramatically larger numbers.

One is US economist Paul Romer, who shared the 2018 Nobel Prize for economics for his work on the importance of knowledge and ideas in the economy. In late March he modelled a “frequent testing policy” in which:

7% of the population is randomly selected for testing each day. Over the 500 days illustrated in the plots and the animation, this means that the average person is tested about 30 times in 500 days – roughly once very two weeks.

This rate of testing would mean testing close to 2 million Australians a day. But even that is probably not enough.

The mathematics of mass testing

To appreciate why an even large number of tests is needed, imagine purely random testing is being used. That is, testing not focused on “hot spots” as has been the case in Melbourne.

Testing, tracing and isolating will only be effective if, on average, the process identifies cases before those people transmit the virus. Epidemiologists call the number of infections caused by a single case the “reproduction” (R) number. If it’s less than 1, the pandemic will die out. If it’s more than 1, the virus spreads.

When uncontrolled, COVID-19 spreads roughly once every six days. This corresponds to a reproduction number of 2.5 over the 15 days a person with COVID-19 is generally infectious.

Moreover, as Romer notes, current tests are far from perfect. He assumes a 20% false negative rate (tests results saying someone doesn’t have COVID-19 when they do) and a 1% false positive rate (results saying someone has it when they don’t).

The mathematics says to control the disease we need to test the entire population roughly every four days.

In a paper published by Harvard University’s Edmond J. Safra Center for Ethics, Divya Siddarth and Glen Weyl] calculate the 20% who are false negatives will, on average, pass the virus to 2.5 people. The other 80% of cases are caught on average halfway through the testing cycle.

To put it in basic maths terms, if we test people every “x” days, we catch those infections on average after half that time (x/2 days). To keep the effective reproduction rate at, say, 0.75 we need “x” to be 3.75. That means testing everyone roughly once every four days.

And that would mean testing more than 6.5 million Australians a day. Yikes!

Asymptomatic cases

Given the scale needed to make random testing a success, it is perhaps not surprising authorities have opted for targeted testing – focusing on transmission hot spots.

But Siddarth and Weyl explain the fatal flaw with any testing strategy reacting only to symptomatic cases:

By the time symptomatic patients show up, they will already have infected .833 people. Furthermore, 20% of those infected will be asymptomatic throughout the time they have the disease, and 20% of those tested will yield false negatives. This means that a policy of only testing those who present with symptoms and only quarantining those who test positive will lead an average infected individual to infect others at a rate of 1.4.

Being above 1, this means the virus still grows exponentially.




Read more:
Coronavirus: asymptomatic people can still develop lung damage


Testing with contact tracing

A better solution is to test based on rigorous contact tracing of known infections. This is why governments pinned such great hopes on the technology of tracing apps such as Australia’s COVIDSafe.

Siddarth and Weyl consider a kind of best-case scenario that traces everyone an infectious person has come into contact with, and everyone those people have come into contact with as well. They calculate this could lead to tracking down 75% of cases. Other transmission would be pursued through prompt testing of everyone with symptoms.

In the US this would require about 2 million tests a day. In Australia it would need about 150,000 tests a day – three times as many tests as are being done now.

Group testing

An intriguing solution is “group testing”. This idea has been around since the 1940s and involves pooling patient specimens for testing. If the pooled test is negative, the whole group is cleared. If the test is positive, more focused testing is done to identify individual cases.




Read more:
Group testing for coronavirus – called pooled testing – could be the fastest and cheapest way to increase screening nationwide


The question, then, is what is the optimal group-testing strategy? For instance, what is the best group size to choose? Should some people be placed in multiple groups? Should there be multiple stages of group testing?

In a US National Bureau of Economic Research working paper published this month, four scholars from the University of California Berkeley show how machine learning can help to determine the optimal strategy.

For example, optimal group test size depends on the prevalence of the virus in the population. By estimating individual risk profiles – a person’s age, pre-existing health problems, where they live, if they work in a job that exposes them to risks, and so on – it is possible to target tests more efficiently than if treating everyone as equally at risk.

The goal is to improve predictive accuracy by incorporating as many observable characteristics that may influence risk as possible. This is a classic problem for “supervised machine learning”. Using machine learning could make group testing perhaps four to five times more efficient, the Berkeley researchers suggest.

Done this way, we might be able to achieve an effective strategy by testing as few as 30,000 to 40,000 Australians a day.

But the approach will need to be very different from now.

Our pre-vaccine future

Until an effective vaccine is found and widely deployed, testing is crucial to control COVID-19.

As the Berkeley authors emphasise, modern analytic techniques can make “high-frequency, intelligent group testing a powerful new tool in the fight against COVID-19, and potentially other infectious diseases”.

We need all the tools we can find.The Conversation

Richard Holden, Professor of Economics, UNSW

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.

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


Adam Kamradt-Scott, University of Sydney

Data on COVID-19 testing rates per thousand people show that Australia is doing extremely well compared to many other countries.

This gives us a reasonable level of confidence that we are detecting most of the COVID-19 cases across the country.

The prospects of elimination remain elusive but even with the current outbreak in Victoria, Australia is continuing to maintain a high level of surveillance.

In terms of the broader consequences, including deaths per 1,000 people, Australia is among the best in the world when it comes to responding to the pandemic.

That doesn’t mean we can afford to be complacent. To retain this current status, we need to maintain a high level of testing. We also need every person in Australia to take the coronavirus threat seriously and stick to the basics: physical distancing, staying home if unwell, washing hands, and getting tested if you have any symptoms at all.




Read more:
Cases, deaths and coronavirus tests: how Australia compares to the rest of the world


Use the tool below, which uses data from Our World in Data, to explore how each country compares on:

  • the total number of COVID-19 cases
  • the total number of cases per million people
  • the number of daily new confirmed cases
  • the number of daily new confirmed cases per million people.

On COVID-19 fatalities for each country, you can see:

  • the total number of deaths
  • the total number of deaths per million people
  • the number of daily new deaths
  • the number of daily new deaths per million people.

And for tests performed by each country (except China, which Our World in Data says has limited publicly available data on testing rates nationwide), you can see:

  • the total number of tests performed
  • the total tests per thousand people
  • the number of daily new tests
  • the number of daily new tests per 1,000 people.
Data visualisation: Kaho Cheung https://observablehq.com/@unkleho/covid-19-bubble-chart-with-d3-render. Data source: Our World in Data https://ourworldindata.org. New deaths, cases and tests refers to new daily confirmed deaths, cases and tests. Countries with a population under 1 million not shown.



Read more:
Coronavirus pandemic shows it’s time for an Australian Centre for Disease Control – in Darwin


The Conversation


Adam Kamradt-Scott, Associate professor, University of Sydney

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.