How contagious is Delta? How long are you infectious? Is it more deadly? A quick guide to the latest science


Shutterstock

Lara Herrero, Griffith UniversityDelta was recognised as a SARS-CoV-2 variant of concern in May 2021 and has proved extremely difficult to control in unvaccinated populations.

Delta has managed to out-compete other variants, including Alpha. Variants are classified as “of concern” because they’re either more contagious than the original, cause more hospitalisations and deaths, or are better at evading vaccines and therapies. Or all of the above.

So how does Delta fare on these measures? And what have we learnt since Delta was first listed as a variant of concern?




Read more:
Is Delta defeating us? Here’s why the variant makes contact tracing so much harder


How contagious is Delta?

The R0 tells us how many other people, on average, one infected person will pass the virus on to.

Delta has an R0 of 5-8, meaning one infected person passes it onto five to eight others, on average.

This compares with an R0 of 1.5-3 for the original strain.

So Delta is twice to five times as contagious as the virus that circulated in 2020.



The Conversation, CC BY-ND

What happens when you’re exposed to Delta?

SARS-CoV-2 is the virus that causes COVID-19. SARS-CoV-2 is transmitted through droplets an infected person releases when they breathe, cough or sneeze.

In some circumstances, transmission also occurs when a person touches a contaminated object, then touches their face.

Four Turkish men walk across an open town space.
One person infected with Delta infects, on average, five to eight others.
Shutterstock

Once SARS-CoV-2 enters your body – usually through your nose or mouth – it starts to replicate.

The period from exposure to the virus being detectable by a PCR test is called the latent period. For Delta, one study suggests this is an average of four days (with a range of three to five days).

That’s two days faster than the original strain, which took roughly six days (with a range of five to eight days).



The Conversation, CC BY-ND

The virus then continues to replicate. Although often there are no symptoms yet, the person has become infectious.

People with COVID-19 appear to be most infectious two days before to three days after symptoms start, though it’s unclear whether this differs with Delta.

The time from virus exposure to symptoms is called the incubation period. But there is often a gap between when a person becomes infectious to others to when they show symptoms.

As the virus replicates, the viral load increases. For Delta, the viral load is up to roughly 1,200 times higher than the original strain.

With faster replication and higher viral loads it is easy to see why Delta is challenging contact tracers and spreading so rapidly.

What are the possible complications?

Like the original strain, the Delta variant can affect many of the body’s organs including the lungs, heart and kidneys.

Complications include blood clots, which at their most severe can result in strokes or heart attacks.

Around 10-30% of people with COVID-19 will experience prolonged symptoms, known as long COVID, which can last for months and cause significant impairment, including in people who were previously well.

Woman in a mask waits in hospital waiting room.
Even previously well people can get long COVID.
Shutterstock

Longer-lasting symptoms can include fatigue, shortness of breath, chest pain, heart palpitations, headaches, brain fog, muscle aches, sleep disturbance, depression and the loss of smell and taste.

Is it more deadly?

Evidence the Delta variant makes people sicker than the original virus is growing.

Preliminary studies from Canada and Singapore found people infected with Delta were more likely to require hospitalisation and were at greater risk of dying than those with the original virus.

In the Canadian study, Delta resulted in a 6.1% chance of hospitalisation and a 1.6% chance of ICU admission. This compared with other variants of concern which landed 5.4% of people in hospital and 1.2% in intensive care.

In the Singapore study, patients with Delta had a 49% chance of developing pneumonia and a 28% chance of needing extra oxygen. This compared with a 38% chance of developing pneumonia and 11% needing oxygen with the original strain.

Similarly, a published study from Scotland found Delta doubled the risk of hospitalisation compared to the Alpha variant.

Older man with cold symptoms lays down, wrapped in a blanket, cradling his head, holding a tissue to his nose.
Emerging evidence suggests Delta is more likely to cause severe disease than the original strain.
Shutterstock

How do the vaccines stack up against Delta?

So far, the data show a complete course of the Pfizer, AstraZeneca or Moderna vaccine reduces your chance of severe disease (requiring hospitalisation) by more than 85%.

While protection is lower for Delta than the original strain, studies show good coverage for all vaccines after two doses.

Can you still get COVID after being vaccinated?

Yes. Breakthrough infection occurs when a vaccinated person tests positive for SARS-Cov-2, regardless of whether they have symptoms.

Breakthrough infection appears more common with Delta than the original strains.

Most symptoms of breakthrough infection are mild and don’t last as long.

It’s also possible to get COVID twice, though this isn’t common.

How likely are you to die from COVID-19?

In Australia, over the life of the pandemic, 1.4% of people with COVID-19 have died from it, compared with 1.6% in the United States and 1.8% in the United Kingdom.

Data from the United States shows people who were vaccinated were ten times less likely than those who weren’t to die from the virus.

The Delta variant is currently proving to be a challenge to control on a global scale, but with full vaccination and maintaining our social distancing practices, we reduce the spread.




Read more:
Why is Delta such a worry? It’s more infectious, probably causes more severe disease, and challenges our vaccines


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.

The Lambda variant: is it more infectious, and can it escape vaccines? A virologist explains


The Lambda variant accounts for almost all new cases in Peru, which has the world’s highest COVID death toll per capita.
Rodrigo Abd/AP/AAP

Adam Taylor, Griffith UniversityThe Lambda coronavirus variant was first reported in Peru in December 2020, according to the World Health Organization (WHO).

It then spread to multiple countries in South America, where it currently accounts for over 20% of detected variants.

One case of Lambda was recorded in hotel quarantine in New South Wales in April.

Lambda has now been detected in more than 20 countries around the globe.

The European Centre for Disease Prevention and Control has designated Lambda a “variant under monitoring”, and Public Health England regards it as a “variant under investigation”.

In June this year, the WHO designated it a “variant of interest”. This is due to mutations thought to affect the virus’ characteristics, such as how easily it’s transmitted. Though it’s not yet concerning enough for the WHO to deem it a “variant of concern”, such as Alpha or Delta.

Epidemiological evidence is still mounting as to the exact threat Lamda poses. So, at this stage more research is required to say for certain how its mutations impact transmission, its ability to evade protection from vaccines, and the severity of disease.

Preliminary evidence suggests Lambda has an easier time infecting our cells and is a bit better at dodging our immune systems. But vaccines should still do a good job against it.

Is Lambda more infectious? And can it escape vaccines?

Mutations affecting the spike protein of the SARS-CoV-2 virus can increase infectivity, which is the ability of the virus to infect cells.

What’s more, as many of the coronavirus vaccines currently available or in development are based on the spike protein, changes to the spike protein in new variants can impact vaccine effectiveness

Lambda contains multiple mutations to the spike protein.

One mutation (F490S) has already been associated with reduced susceptibility to antibodies generated in patients who had recovered from COVID. This means antibodies generated from being infected with the original Wuhan strain of COVID aren’t quite as effective at neutralising Lambda.

Another Lambda mutation (L452Q) is at the same position in the spike protein as a previously studied mutation found in the Delta variant (L452R). This mutation in Delta not only increases the ability of the virus to infect cells, but also promotes immune escape meaning the antibodies vaccines generate are less likely to recognise it.

Both mutations F490S and L452Q are in the “receptor binding domain”, which is the part of the spike protein that attaches to our cells.




Read more:
Why is Delta such a worry? It’s more infectious, probably causes more severe disease, and challenges our vaccines


Preliminary data on the Lambda spike protein suggests it has increased infectivity, meaning it’s more easily able to infect cells than the original Wuhan virus and the Alpha and Gamma variants. These early studies also suggest antibodies generated in people receiving the CoronaVac vaccine (developed by Chinese biotech Sinovac) were less potent at neutralising the spike protein of Lambda than they were the Wuhan, Alpha or Gamma variants.

It’s worth noting infectivity is not the same as being more infectious between people. There’s not enough evidence yet that Lambda is definitely more infectious, but the mutations it has suggest it’s possible.

A separate small study, also yet to be reviewed by the scientific community, suggests the L452Q mutation in the Lambda spike protein is responsible for its increased ability to infect cells. Like the L452R mutation in the Delta variant, this study suggests the L452Q mutation means Lambda may bind more easily to the “ACE2 receptor”, which is the gateway for SARS-CoV-2 to enter our cells.

This preliminary study suggests Lambda’s spike protein mutations reduce the ability of antibodies generated by both Pfizer and Moderna’s vaccines to neutralise the virus. Also, one mutation was shown to resist neutralisation by antibodies from antibody therapy to some extent.




Read more:
What monoclonal antibodies are – and why we need them as well as a vaccine


However, these reductions were moderate. Also, neutralising antibodies are only one part of a protective immune response elicited by vaccination. Therefore, these studies conclude currently approved vaccines and antibody therapies can still protect against disease caused by Lambda.

Is it more severe?

A risk assessment released by Public Health England in July concedes there’s not yet enough information on Lambda to know whether infection increases the risk of severe disease.

The risk assessment also recommends ongoing surveillance in countries where both Lambda and Delta are present be implemented as a priority. The aim would be to find out whether Lambda is capable of out-competing Delta.

With ongoing high levels of transmission of the coronavirus, there’s a continued risk of new variants emerging. The Lambda variant again highlights the risk of these mutations increasing the ability of SARS-CoV-2 to infect cells or disrupt existing vaccines and antibody drugs.

The WHO will continue to study Lambda to determine whether it has the potential to become an emerging risk to global public health and a variant of concern.The Conversation

Adam Taylor, Early Career Research Leader, Emerging Viruses, Inflammation and Therapeutics Group, Menzies Health Institute Queensland, Griffith University

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

Why is Delta such a worry? It’s more infectious, probably causes more severe disease, and challenges our vaccines


Shutterstock

Michael Toole, Burnet InstituteWhile Australians may be focused on the havoc the Delta variant is wreaking on our shores, Delta is in fact driving waves of COVID infections all around the world.

With the World Health Organization (WHO) warning Delta will rapidly become the dominant strain, let’s take a look at this variant in a global context.

The rise and rise of Delta

The Delta variant (B.1.617.2) emerged quietly in the Indian state of Maharashtra in October 2020. It barely caused a ripple at a time when India was reporting around 40,000 to 80,000 cases a day, most being the Alpha variant (B.1.1.7) first found in the United Kingdom.

That changed in April when India experienced a massive wave of infections peaking at close to 400,000 daily cases in mid-May. The Delta variant rapidly emerged as the dominant strain in India.

The WHO designated Delta as a variant of concern on May 11, making it the fourth such variant.

The Delta variant rapidly spread around the world and has been identified in at least 98 countries to date. It’s now the dominant strain in countries as diverse as the UK, Russia, Indonesia, Vietnam, Australia and Fiji. And it’s on the rise.

In the United States, Delta made up one in five COVID cases in the two weeks up to June 19, compared to just 2.8% in the two weeks up to May 22.

Meanwhile, the most recent Public Health England weekly update reported an increase of 35,204 Delta cases since the previous week. More than 90% of sequenced cases were the Delta variant.

In just two months, Delta has replaced Alpha as the dominant strain of SARS-CoV-2 in the UK. The increase is primarily in younger age groups, a large proportion of whom are unvaccinated.

2 key mutations

Scientists have identified more than 20 mutations in the Delta variant, but two may be crucial in helping it transmit more effectively than earlier strains. This is why early reports from India called it a “double mutant”.

The first is the L452R mutation, which is also found in the Epsilon variant, designated by the WHO as a variant of interest. This mutation increases the spike protein’s ability to bind to human cells, thereby increasing its infectiousness.

Preliminary studies also suggest this mutation may aid the virus in evading the neutralising antibodies produced by both vaccines and previous infection.

A woman wearing a mask crosses the street in New York.
Evidence shows the Delta variant is more infectious. We can understand why by looking at its mutations.
Shutterstock

The second is a novel T478K mutation. This mutation is located in the region of the SARS-CoV-2 spike protein which interacts with the human ACE2 receptor, which facilitates viral entry into lung cells.

The recently described Delta Plus variant carries the K417N mutation too. This mutation is also found in the Beta variant, against which COVID vaccines may be less effective.




Read more:
What’s the ‘Delta plus’ variant? And can it escape vaccines? An expert explains


One good thing about the Delta variant is the fact researchers can rapidly track it because its genome contains a marker the previously dominant Alpha variant lacks.

This marker — known as the “S gene target” — can be seen in the results of PCR tests used to detect COVID-19. So researchers can use positive S-target hits as a proxy to quickly map the spread of Delta, without needing to sequence samples fully.

Why is Delta a worry?

The most feared consequences of any variant of concern relate to infectiousness, severity of disease, and immunity conferred by previous infection and vaccines.

WHO estimates Delta is 55% more transmissible than the Alpha variant, which was itself around 50% more transmissible than the original Wuhan virus.

That translates to Delta’s effective reproductive rate (the number of people on average a person with the virus will infect, in the absence of controls such as vaccination) being five or higher. This compares to two to three for the original strain.

There has been some speculation the Delta variant reduces the so-called “serial interval”; the period of time between an index case being infected and their household contacts testing positive. However, in a pre-print study (a study which hasn’t yet been peer-reviewed), researchers in Singapore found the serial interval of household transmission was no shorter for Delta than for previous strains.

One study from Scotland, where the Delta variant is predominating, found Delta cases led to 85% higher hospital admissions than other strains. Most of these cases, however, were unvaccinated.

The same study found two doses of Pfizer offered 92% protection against symptomatic infection for Alpha and 79% for Delta. Protection from the AstraZeneca vaccine was substantial but reduced: 73% for Alpha versus 60% for Delta.

A study by Public Health England found a single dose of either vaccine was only 33% effective against symptomatic disease compared to 50% against the Alpha variant. So having a second dose is extremely important.

In a pre-print article, Moderna revealed their mRNA vaccine protected against Delta infection, although the antibody response was reduced compared to the original strain. This may affect how long immunity lasts.




Read more:
The symptoms of the Delta variant appear to differ from traditional COVID symptoms. Here’s what to look out for


A global challenge to controlling the pandemic

The Delta variant is more transmissible, probably causes more severe disease, and current vaccines don’t work as well against it.

WHO warns low-income countries are most vulnerable to Delta as their vaccination rates are so low. New cases in Africa increased by 33% over the week to June 29, with COVID-19 deaths jumping 42%.

There has never been a time when accelerating the vaccine rollout across the world has been as urgent as it is now.

WHO chief Tedros Adhanom Gebreyesus has warned that in addition to vaccination, public health measures such as strong surveillance, isolation and clinical care remain key. Further, tackling the Delta variant will require continued mask use, physical distancing and keeping indoor areas well ventilated.The Conversation

Michael Toole, Professor of International Health, Burnet Institute

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

The UK variant is likely deadlier, more infectious and becoming dominant. But the vaccines still work well against it


Kirsty Short, The University of Queensland

New research published this week in the British Medical Journal found the coronavirus variant originating in the United Kingdom, called B.1.1.7, is substantially more deadly than the original strain of SARS-CoV-2.

The authors say the B.1.1.7 variant is between 32 and 104% deadlier. However, it’s important to recognise these data were only collected from one group of people so more research is needed to see if these numbers hold true in other groups of patients.

The B.1.1.7 variant is becoming the dominant virus in many parts of the world, and is more infectious than the original strain (UK authorities have suggested it’s up to 70% more transmissible). This makes sense because a virus can become more transmissible as it evolves. However, it’s actually a strange thing for a virus to become more deadly over time (more on that later).

The good news is preliminary data suggest COVID vaccines still perform very well against this variant.

What did the study find?

There are two ways to check if someone has this variant. The first is by doing full genomic sequencing, which takes time and resources. The other, easier way, is to analyse results from the standard PCR test, which normally takes a swab from your nose and throat.

This test targets two viral genes in the swab sample, one of which doesn’t work very well with this variant (it’s called the “S-gene”). So if someone was positive for one of these genes, but negative for the “S-gene”, there’s a good chance they’re infected with the B.1.1.7 variant.

The study authors looked at the S-gene status of 109,812 people with COVID, and looked at how many died. They found S-gene negative people had a higher chance of dying 28 days after testing positive for the virus. The study “matched” patients in the S-gene positive and S-gene negative groups based on various factors (including age) to ensure these factors didn’t confound the results.




Read more:
UK, South African, Brazilian: a virologist explains each COVID variant and what they mean for the pandemic


This matches a report from the UK government’s New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG), which said in January there’s a “realistic possibility” infection with this strain is linked with a higher chance of death.

With increased death from a variant, you would also expect to see increased hospitalisations and ICU admissions in places where the variant is surging. We’re still waiting for better data on this, but one Danish study suggested an increased risk of hospitalisation from this variant.

But why is it more deadly?

Viruses have a selective advantage (meaning they’re more likely to outcompete other viruses) if they’re able infect more hosts. It’s also advantageous for the virus if they can evade the host’s immune response, because it helps them survive longer and reproduce more.

But it’s actually quite strange for this variant to be more deadly. There’s not a selective advantage for a virus to kill its host, because it might kill its host before they transmit the virus.

Scientists still need to find out why this variant is more deadly, and how it came about.

One possibility is this variant’s increased disease severity is linked to its increased transmissibility. For example, it could be that because it’s more infectious, it’s leading to larger clusters of infection including in places like aged care homes, which we know are linked to more deaths. We don’t know for sure yet.

Vaccines still respond well to this variant

It’s important to note the current crop of vaccines still perform well against the variant.

A slight drop in the numbers of neutralising antibodies responding to the B.1.1.7 virus was recorded after vaccination with vaccines from Novavax and Moderna. But the protection these vaccines offer should still be sufficient to prevent severe disease. This variant also had a negligible impact on the function of T-cells, which can kill virus-infected cells and help control the infection.

Preliminary data suggest people given the AstraZeneca vaccine also experienced a mild decrease in the number of circulating antibodies when infected with the B.1.1.7 variant. But again, the effect was relatively modest, and the authors say the efficacy of the vaccine against this variant is similar to that of the original Wuhan strain of the virus.




Read more:
COVID-19 vaccine FAQs: Efficacy, immunity to illness vs. infection (yes, they’re different), new variants and the likelihood of eradication


It’s becoming dominant

The B.1.1.7 variant is becoming the dominant strain in many parts of the world. The ABC reports it’s dominant in at least 10 countries.

In the UK it represents around 98% of new cases, and up to 90% of new cases in some parts of Spain.

In Denmark, new cases from this variant were around 0.3% in November last year, rising to 65% of new cases in February. It accounts for more than two-thirds of new cases in the Netherlands.

In the United States, the states of Florida, Texas and California (among others) are seeing significant increases in the number of cases from this variant.

It’s possible the spread of this variant is even higher than reported. The ability to detect its spread is dependent on how often genomic sequencing is done, and many countries aren’t currently in the position to do regular genomic testing.

There’s a suggestion from some researchers and commentators the variant is linked with a surge in cases among kids. However, this observation remains largely anecdotal and it’s unclear if this simply reflects rising total case numbers in certain places.The Conversation

Kirsty Short, Senior Lecturer, The University of Queensland

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

WHO reform: a call for an early-warning protocol for infectious diseases


Peter Gluckman and Alexander Gillespie, University of Waikato

The World Health Organization (WHO) has come in for its share of criticism for its handling of the COVID-19 pandemic. While some faults are the responsibility of the WHO, others were caused by member states, which did not always act as quickly as they should have.

In our opinion, the fundamental problem was that the WHO’s current information sharing, response and organisational structure to deal with infectious diseases that may spread across borders quickly and dangerously is out of date.

We argue the global population deserves a better model — one that delivers information about the risk of emergent infectious diseases faster and in a way that is transparent, verifiable and non-politicised.

Preparing for the next pandemic

More than one million people have died of COVID-19, and that number could double before the pandemic is brought under control.

COVID-19 is not the first pandemic, nor will it be the last. The WHO was also criticised after the 2014 Ebola epidemic.




Read more:
The WHO’s coronavirus inquiry will be more diplomatic than decisive. But Australia should step up in the meantime


Global responses to such threats have precedents dating back to 1851 and the development of stardardised quarantine regulations. The international initiatives that have since followed, punctuated by the formation of leading international bodies such as the WHO in 1946, represent incremental progress. The most recent iteration of work in this area is the International Health Regulations of 2005.

We suggest a new protocol should be added to the WHO. We have drafted a tentative discussion document, which is available upon request, based on the following six broad ideas.




Read more:
The next once-a-century pandemic is coming sooner than you think – but COVID-19 can help us get ready


1. The WHO remains the central decision-making body

We want to strengthen the collection and sharing of information related to infectious diseases, but we believe the WHO must remain the international entity that interprets the material, raises alerts for the global community and organises responses.

Despite retaining the centrality of the WHO, we suggest a new protocol to provide the basis for the independent collection, sharing and transfer of information between countries and with the WHO. Fundamentally, we want the early-warning science to be divorced from the policy responses.

2. Obligation to issue risk warning

A clear and binding legal principle needs to be explicitly written into international law: namely, that there is an obligation to pass on, as quickly as possible, information about a hazardous risk discovered in one country that could be dangerous to others.

The international community first saw this thinking in the 1986 Convention on Early Notification of a Nuclear Accident, developed after the Chernobyl incident. We believe the same thinking should be carried over to the early notification of infectious disease threats, as they are just as great.

3. Independence in science

We need legally binding rules for the collection and sharing of information related to infectious diseases. These rules must be detailed, but have the capacity to evolve. This principle is already developing, beginning with innovative solutions to problems like regional air pollution, which separates scientists from decision-makers and removes any potential for partisan advice.

The core of this idea needs to be adapted for infectious diseases and placed within its own self-contained protocol. Signatories can then continually refine the scientific needs, whereby scientists can update what information should be collected and shared, so decision-makers can react in good time, with the best and most independent information at their fingertips.

4. Objectivity and openness

We must articulate the principle that shared scientific information should be as comprehensive, objective, open and transparent as possible. We have borrowed this idea from the Intergovernmental Panel on Climate Change (IPCC) but it needs to be supplemented by the particular requirement to tackle emergent infectious disease risks.

This may include clinical and genetic information and the sharing of biological samples to allow rapid laboratory, medical and public health developments. Incomplete information should not be a reason to delay and all information should be open source. It will also be important to add a principle from international environmental law of acting in a precautionary manner.

In the case of early notification about infectious diseases, we contend that even if there is a lack of scientific certainty over an issue, it is not a reason to hold back from sharing the information.

5. Deployment to other countries

We realise information sometimes needs to be verified independently and quickly. Our thinking here has been guided by the Chemical Weapons Convention and the use of challenge inspections. This mechanism, in times of urgency, allows inspectors to go anywhere at any time, without the right of refusal, to provide independent third-party verification.

In the case of infectious diseases, a solution might be that in times of urgency, if 75% of the members of the new protocol agree, specialist teams are deployed quickly to any country to examine all areas (except military spaces) from where further information is required. This information would then be quickly fed back into the mechanisms of the protocol.

6. Autonomy and independent funding

We suggest such a protocol must be self-governing and largely separate from the WHO, and it is essential it has its own budget and office.

This will increase the autonomy of the early-warning system and reduce the risks of being reliant on the WHO for funding (with all the vagaries that entails). If well designed, the protocol should provide a better way for state and non-state actors to contribute.

The goodwill and financial capacity of international philanthropy, transnational corporations and civil society will need to be mobilised to a much greater degree to fund the new protocol.


The authors worked with Sir Jim McLay, whose leadership contribution and input on the proposed protocol has been integral to the project.The Conversation

Peter Gluckman, Director of Koi Tū, the Centre for Informed Futures; former Chief Science Advisor to the Prime Minister of New Zealand and Alexander Gillespie, Professor of Law, University of Waikato

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

How long are you infectious when you have coronavirus?



Shutterstock

Tambri Housen, Australian National University; Amy Elizabeth Parry, Australian National University, and Meru Sheel, Australian National University

As the coronavirus pandemic stretches on, a small proportion of Australians infected have now died, while most have either recovered, or are likely to recover over the next few weeks.

One thing many of us want to know is for how long people who have SARS-CoV-2, the virus that causes COVID-19, are able to pass it on to someone else.

Let’s look at what the science tells us so far.

How long does it take to get sick?

The “incubation period” is the time between being exposed to the virus and the onset of symptoms.

For COVID-19, the incubation period ranges from 1 to 14 days. But most people who develop COVID-19 symptoms do so 4 to 6 days after exposure.




Read more:
Coronavirus: how long does it take to get sick? How infectious is it? Will you always have a fever? COVID-19 basics explained


How long are you infectious?

The “infectious period” means the time you’re able to spread the virus to someone else.

For COVID-19, there is emerging evidence to suggest the infectious period may start 1 to 3 days before you develop symptoms.

The most infectious period is thought to be 1 to 3 days before symptoms start, and in the first 7 days after symptoms begin. But some people may remain infectious for longer.

Commonly reported symptoms for COVID-19 – such as fever, cough and fatigue – usually last around 9 to 10 days but this can be longer.


The Coversation, CC BY-ND

Why are some people infectious for longer?

Typically with viruses, the higher the viral load (the more virus circulating in the body), the higher the risk of transmission through known transmission pathways.

A study conducted in Hong Kong looking at viral load in 23 patients diagnosed with COVID-19 found higher viral loads in the first week of illness.

Another study from China looking at 76 hospitalised patients found that by 10 days after symptom onset, mild cases had cleared the virus. That is, no virus was detectable through testing.

However, severe cases have much higher viral loads and many continue to test positive beyond the 10 days after symptoms start.

So the more severe the illness and the higher the viral load, the longer you continue to shed the virus and are infectious.




Read more:
How can I treat myself if I’ve got – or think I’ve got – coronavirus?


When are you no longer infectious?

If someone has been symptom-free for 3 days and they developed their first symptoms more than 10 days prior, they are no longer considered to be infectious.

But we’re not sure whether people are infectious when they have recovered but the virus can still be detected in their bodies.

One study from Hong Kong found the virus could be detected for 20 days or longer after the initial onset of symptoms in one-third of patients tested.

Another study from China found found the virus in a patients’ faecal samples five weeks after the first onset of symptoms.

But the detection of the virus doesn’t necessarily mean the person is infectious. We need more studies with larger sample sizes to get to the bottom of this question.

Should you get tested again before going back into the community?

Due to a global shortage of coronavirus tests, the Commonwealth and state governments have strict criteria about who should be tested for COVID-19 and when.




Read more:
Who can get tested for coronavirus?


People who have been self-quarantining, because they had contact with a confirmed case of COVID-19 and have completed their 14-day quarantine period without developing symptoms, can return to the community. There is no requirement to be tested prior to returning to the community. It is, however, recommended they continue to practise social distancing and good hygiene as a precaution.

The requirements are different for people who have been diagnosed with COVID-19.

At present, re-testing people who have experienced mild illness, and have recovered from COVID-19 is not recommended. A person is considered safe to return to the community and discontinue self-isolation if they are no longer infectious. This means they developed their first symptoms more than 10 days prior and have not experienced any symptoms for at least 3 days (72 hours).

For people who have been hospitalised with more severe illness, the testing requirements before discharge are different. They will have two swabs taken 24 hours apart to check if they have cleared the virus. If the swabs are both negative, they can be discharged and don’t require further self-isolation.

If one or both tests are positive but the person is well enough to go home, they must continue to self-isolate for at least 10 days since they were discharged from hospital and they have not experienced any symptoms for at least 3 days.

There are also different testing requirements for people working or living in high-risk settings. If you work or live in a high-risk setting you should consult with your health care provider on re-testing requirements.The Conversation

Tambri Housen, Epidemiologist | Senior Research Fellow, National Centre for Epidemiology and Population Health, Australian National University; Amy Elizabeth Parry, Epidemiologist | PhD Candidate, National Centre for Epidemiology and Population Health, Australian National University, and Meru Sheel, Epidemiologist | Senior Research Fellow, Australian National University

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

Egyptian Couple Shot by Muslim Extremists Undaunted in Ministry


Left for dead, Christians offer to drop charges if allowed to construct church building.

CAIRO, Egypt, June 9 (CDN) — Rasha Samir was sure her husband, Ephraim Shehata, was dead.

He was covered with blood, had two bullets inside him and was lying facedown in the dust of a dirt road. Samir was lying on top of him doing her best to shelter him from the onslaught of approaching gunmen.

With arms outstretched, the men surrounded Samir and Shehata and pumped off round after round at the couple. Seconds before, Samir could hear her husband mumbling Bible verses. But one bullet had pierced his neck, and now he wasn’t moving. In a blind terror, Samir tried desperately to stop her panicked breathing and convincingly lie still, hoping the gunmen would go away.

Finally, the gunfire stopped and one of the men spoke. “Let’s go. They’re dead.”

 

‘Break the Hearts’

On the afternoon of Feb. 27, lay pastor Shehata and his wife Samir were ambushed on a desolate street by a group of Islamic gunmen outside the village of Teleda in Upper Egypt.

The attack was meant to “break the hearts of the Christians” in the area, Samir said.

The attackers shot Shehata twice, once in the stomach through the back, and once in the neck. They shot Samir in the arm. Both survived the attack, but Shehata is still in the midst of a difficult recovery. The shooters have since been arrested and are in jail awaiting trial. A trial cannot begin until Shehata has recovered enough to attend court proceedings.

Despite this trauma, being left with debilitating injuries, more than 85,000 Egyptian pounds (US$14,855) in medical bills and possible long-term unemployment, Shehata is willing to drop all criminal charges against his attackers – and avoid what could be a very embarrassing trial for the nation – if the government will stop blocking Shehata from constructing a church building.

Before Shehata was shot, one of the attackers pushed him off his motorcycle and told him he was going to teach him a lesson about “running around” or being an active Christian.

Because of his ministry, the 34-year-old Shehata, a Coptic Orthodox Christian, was arguably the most visible Christian in his community. When he wasn’t working as a lab technician or attending legal classes at a local college, he was going door-to-door among Christians to encourage them in any way he could. He also ran a community center and medical clinic out of a converted two-bedroom apartment. His main goal, he said, was to “help Christians be strong in their faith.”

The center, open now for five years, provided much-needed basic medical services for surrounding residents for free, irrespective of their religion. The center also provided sewing training and a worksite for Christian women so they could gain extra income. Before the center was open in its present location, he ran similar services out of a relative’s apartment.

“We teach them something that can help them with the future, and when they get married they can have some way to work and it will help them get money for their families,” Shehata said.

Additionally, the center was used to teach hygiene and sanitation basics to area residents, a vital service to a community that uses well water that is often polluted or full of diseases. Along with these services, Shehata and his wife ran several development projects, repairing the roofs of shelters for poor people, installing plumbing, toilets and electrical systems. The center also distributed free food to the elderly and the infirm.

The center has been run by donations and nominal fees used to pay the rent for the apartment. Shehata has continued to run the programs as aggressively as he can, but he said that even before the shooting that the center was barely scraping by.

“We have no money to build or improve anything,” he said. “We have a safe, but no money to put in it.”

 

Tense Atmosphere

In the weeks before the shooting, Teleda and the surrounding villages were gripped with fear.

Christians in the community had been receiving death threats by phone after a Muslim man died during an attack on a Christian couple. On Feb. 2, a group of men in nearby Samalout tried to abduct a Coptic woman from a three-wheeled motorcycle her husband was driving. The husband, Zarif Elia, punched one of the attackers in the nose. The Muslim, Basem Abul-Eid, dropped dead on the spot.

Elia was arrested and charged with murder. An autopsy later revealed that the man died of a heart attack, but local Muslims were incensed.

Already in the spotlight for his ministry activities, Shehata heightened his profile when he warned government officials that Christians were going to be attacked, as they had been in Farshout and Nag Hammadi the previous month. He also gave an interview to a human rights activist that was posted on numerous Coptic websites. Because of this, government troops were deployed to the town, and extremists were unable to take revenge on local Christians – but only after almost the
entire Christian community was placed under house arrest.

“They chose me,” Shehata said, “Because they thought I was the one serving everybody, and I was the one who wrote the government telling them that Muslims were going to set fire to the Christian houses because of the death.”

Because of his busy schedule, Shehata and Samir, 27, were only able to spend Fridays and part of every Saturday together in a village in Samalut, where Shehata lives. Every Saturday after seeing Samir, Shehata would drive her back through Teleda to the village where she lives, close to her family. Samalut is a town approximately 105 kilometers (65 miles) south of Cairo.

On the afternoon of Feb. 27, Shehata and his wife were on a motorcycle on a desolate stretch of hard-packed dirt road. Other than a few scattered farming structures, there was nothing near the road but the Nile River on one side, and open fields dotted with palm trees on the other.

Shehata approached a torn-up section of the road and slowed down. A man walked up to the vehicle carrying a big wooden stick and forced him to stop. Shehata asked the man what was wrong, but he only pushed Shehata off the motorcycle and told him, “I’m going to stop you from running around,” Samir recounted.

Shehata asked the man to let Samir go. “Whatever you are going to do, do it to me,” he told the man.

The man didn’t listen and began hitting Shehata on the leg with the stick. As Shehata stumbled, Samir screamed for the man to leave them alone. The man lifted the stick again, clubbed Shehata once more on the leg and knocked him to the ground. As Shehata struggled to get up, the man took out a pistol, leveled it at Shehata’s back and squeezed the trigger.

Samir started praying and screaming Jesus’ name. The man turned toward her, raised the pistol once more, squeezed off another round, and shot Samir in the arm. Samir looked around and saw a few men running toward her, but her heart sank when she realized they had come not to help them but to join the assault.

Samir jumped on top of Shehata, rolled on to her back and started begging her attackers for their lives, but the men, now four in all, kept firing. Bullets were flying everywhere.

“I was scared. I thought I was going to die and that the angels were going to come and get our spirits,” Samir said. “I started praying, ‘Please God, forgive me, I’m a sinner and I am going to die.’”

Samir decided to play dead. She leaned back toward her husband, closed her eyes, went limp and tried to stop breathing. She said she felt that Shehata was dying underneath her.

“I could hear him saying some of the Scriptures, the one about the righteous thief [saying] ‘Remember me when you enter Paradise,’” she said. “Then a bullet went through his neck, and he stopped saying anything.”

Samir has no way of knowing how much time passed, but eventually the firing stopped. After she heard one of the shooters say, “Let’s go, they’re dead,” moments later she opened her eyes and the men were gone. When she lifted her head, she heard her husband moan.

 

Unlikely Survival

When Shehata arrived at the hospital, his doctors didn’t think he would survive. He had lost a tremendous amount of blood, a bullet had split his kidney in two, and the other bullet was lodged in his neck, leaving him partially paralyzed.

His heartbeat was so faint it couldn’t be detected. He was also riddled with a seemingly limitless supply of bullet fragments throughout his body.

Samir, though seriously injured, had fared much better than Shehata. The bullet went into her arm but otherwise left her uninjured. When she was shot, Samir was wearing a maternity coat. She wasn’t pregnant, but the couple had bought the coat in hopes she soon would be. Samir said she thinks the gunman who shot her thought he had hit her body, instead of just her arm.

The church leadership in Samalut was quickly informed about the shooting and summoned the best doctors they could, who quickly traveled to help Shehata and Samir. By chance, the hospital had a large supply of blood matching Shehata’s blood type because of an elective surgical procedure that was cancelled. The bullets were removed, and his kidney was repaired. The doctors however, were forced to leave many of the bullet fragments in Shehata’s body.

As difficult as it was to piece Shehata’s broken body back together, it paled in comparison with the recovery he had to suffer through. He endured multiple surgeries and was near death several times during his 70 days of hospitalization.

Early on, Shehata was struck with a massive infection. Also, because part of his internal tissue was cut off from its blood supply, it literally started to rot inside him. He began to swell and was in agony.

“I was screaming, and they brought the doctors,” Shehata said. The doctors decided to operate immediately.

When a surgeon removed one of the clamps holding Shehata’s abdomen together, the intense pressure popped off most of the other clamps. Surgeons removed some stomach tissue, part of his colon and more than a liter of infectious liquid.

Shehata could not eat normally and lost 35 kilograms (approximately 77 lbs.). He also couldn’t evacuate his bowels for at least 11 days, his wife said.

Despite the doctors’ best efforts, infections continued to rage through Shehata’s body, accompanied by alarming spikes in body temperature.

Eventually, doctors sent him to a hospital in Cairo, where he spent a week under treatment. A doctor there prescribed a different regimen of antibiotics that successfully fought the infection and returned Shehata’s body temperature to normal.

Shehata is recovering at home now, but he still has a host of medical problems. He has to take a massive amount of painkillers and is essentially bedridden. He cannot walk without assistance, is unable to move the fingers on his left hand and cannot eat solid food. In approximately two months he will undergo yet another surgery that, if all goes well, will allow him to use the bathroom normally.

“Even now I can’t walk properly, and I can’t lift my leg more than 10 or 20 centimeters. I need someone to help me just to pull up my underwear,” Shehata said. “I can move my arm, but I can’t move my fingers.”

Samir does not complain about her condition or that of Shehata. Instead, she sees the fact that she and her husband are even alive as a testament to God’s faithfulness. She said she thinks God allowed them to be struck with the bullets that injured them but pushed away the bullets that would have killed them.

“There were lots of bullets being shot, but they didn’t hit us, only three or four,” she said. “Where are the others?”

Even in the brutal process of recovery, Samir found cause for thanks. In the beginning, Shehata couldn’t move his left arm, but now he can. “Thank God and thank Jesus, it was His blessing to us,” Samir said. “We were kind of dead, now we are alive."

Still, Samir admits that sometimes her faith waivers. She is facing the possibility that Shehata might not work for some time, if ever. The couple owes the 85,000 Egyptian pounds (US$14,855) in medical bills, and continuing their ministry at the center and in the surrounding villages will be difficult at best.

“I am scared now, more so than during the shooting,” she said. “Ephraim said do not be afraid, it is supposed to make us stronger.”

So Samir prays for strength for her husband to heal and for patience. In the meantime, she said she looks forward to the day when the struggles from the shooting are over and she can look back and see how God used it to shape them.

“There is a great work the Lord is doing in our lives, we may not know what the reason is now, but maybe some day we will,” Samir said.

 

Government Opposition

For the past 10 years, Shehata has tried to erect a church building, or at a minimum a house, that he could use as a dedicated community center. But local Muslims and Egypt’s State Security Investigations (SSI) agency have blocked him every step of the way. He had, until the shooting happened, all but given up on constructing the church building.

On numerous occasions, Shehata has been stopped from holding group prayer meetings after people complained to the SSI. In one incident, a man paid by a land owner to watch a piece of property near the community center complained to the SSI that Shehata was holding prayer meetings at the facility. The SSI made Shehata sign papers stating he wouldn’t hold prayer meetings at the center.

At one time, Shehata had hoped to build a house to use as a community center on property that had been given to him for that purpose. Residents spread a rumor that he was actually erecting a church building, and police massed at the property to prevent him from doing any construction.

There is no church in the town where Shehata lives or in the surrounding villages. Shehata admits he would like to put up a church building on the donated property but says it is impossible, so he doesn’t even try.

In Egypt constructing or even repairing a church building can only be done after a complex government approval process. In effect, it makes it impossible to build a place for Christian worship. By comparison, the construction of mosques is encouraged through a system of subsidies.

“It is not allowed to build a church in Egypt,” Shehata said. “We can’t build a house. We can’t build a community center. And we can’t build a church.”

Because of this, Shehata and his wife organize transportation from surrounding villages to St. Mark’s Cathedral in Samalut for Friday services and sacraments. Because of the lack of transportation options, the congregants are forced to ride in a dozen open-top cattle cars.

“We take them not in proper cars or micro-buses, but trucks – the same trucks we use to move animals,” he said.

The trip is dangerous. A year ago a man fell out of one of the trucks onto the road and died. Shehata said bluntly that Christians are dying in Egypt because the government won’t allow them to construct church buildings.

“I feel upset about the man who died on the way going to church,” he said.

 

Church-for-Charges Swap

The shooters who attacked Shehata and Samir are in jail awaiting trial. The couple has identified each of the men, but even if they hadn’t, finding them for arrest was not a difficult task. The village the attackers came from erupted in celebration when they heard the pastor and his wife were dead.

Shehata now sees the shooting as a horrible incident that can be turned to the good of the believers he serves. He said he finds it particularly frustrating that numerous mosques have sprouted up in his community and surrounding areas during the 10 years he has been prevented from putting up a church building, or even a house. There are two mosques alone on the street of the man who died while being trucked to church services, he said.

Shehata has decided to forgo justice in pursuit of an opportunity to finally construct a church building. He has approached the SSI through church leaders, saying that if he is allowed to construct a church building, then he will take no part in the criminal prosecution of the shooters.

“I have told the security forces through the priests that I will drop the case if they can let us build the church on the piece of land,” he said.

The proposal isn’t without possibilities. His trial has the potential of being internationally embarrassing. It raises questions about fairness in Egyptian society during an upcoming presidential election that will be watched by the world.

Regardless of what happens, Shehata said all he wants is peace and for the rights of Christians to be respected. He said that in Egypt, Christians have less value than the “birds of the air” mentioned in the Bible. According to Luke 12:6, five sparrows sold for two pennies in ancient times.

“We are not to be killed like birds, slaughtered,” he said. “We are human.”

Report from Compass Direct News