Covid: When is the most likely virus to infect others?

Best friend-let’s call him John-I recently called and asked for advice. He woke up with severe muscle aches and malaise. Unsurprisingly, worried that it could be COVID-19, he asked if he should go to work, run to take a test, or stay home. I didn’t know what to do because I had no other symptoms such as fever, cough, or shortness of breath. Of course, this could be another respiratory infection such as the flu or cold, but what about COVID-19? What is the risk of him transmitting the virus to others?

To understand when people with COVID-19 are most likely to get infected, our team conducted a recently published study. Lancet microorganisms..

Viral load (how the viral load in the body changes during infection), viral shedding (the length of time it takes to shed the viral genetic material, not necessarily humans are infected), and isolation I investigated three things. Live virus (a better indicator of human infectivity because it is tested to see if the live virus is isolated and replicated in the laboratory).

Viral load was found to peak in the throat and nose (This is believed to be the main source of infection) Very early stages of illness, especially from the first day of symptoms to the fifth day of symptoms- Mild symptoms..

We also found that for several weeks, genetic material was detected in throat swabs and stool samples. However, no live virus was found in samples collected for more than 9 days. Some people, especially those with severe illness or weakened immunity (such as chemotherapy), Longer viral sheddingThe results suggest that people infected with SARS-CoV-2 are likely to be very infectious a few days before and 5 days after the onset of symptoms.

By comparison, the viral load of Sars peaks 10-14 days after the onset of symptoms, and in the case of Mers it peaks 7-10 days (both Sars and Mers are diseases caused by the coronavirus). .. This explains why infection with these viruses was effectively reduced by quickly finding and quarantining the symptomatic person. It also explains why it was so difficult to contain COVID-19 because it spreads so rapidly in the early stages of the disease.

Contact tracing and modeling studies have also shown that infection is highest during the first 5 days of experiencing symptoms.by Recent researchThe most infectious period is within about 5 days after the onset of symptoms. A Taiwanese and UK contact tracing study found that most contacts were infected if exposed to an infected person within 5 days of the onset of symptoms.

By the time most people get the test results, they may already be the most infected. This early viral load peak suggests that people with COVID-19 need to self-quarantine as soon as symptoms begin without waiting for test results to prevent future infections.

John quickly quarantined himself and called everyone he had contacted in the last few days. The next day he woke up with a mild fever. He couldn’t take the test right away, but could make an appointment later. Results were available by day 5 of his condition. He tested positive for COVID.

Fortunately, John managed to quarantine himself throughout the most infectious period, and his contacts immediately began quarantining.

John was lucky to work from home and get paid.But according to UK survey, Only 1 in 5 can self-quarantine. Barriers include having children at home, having low incomes, experiencing greater financial difficulties during a pandemic, and being a major worker such as a nurse or teacher. And so on.

Government can help more

If your living conditions do not allow quarantine, if you are doing a job that you cannot do from home and your job does not provide sick leave, how can the diagnosis help? And how can a diagnosis help if your family depends on your income to meet basic needs, or if access to your care is related to your employment? ??

This highlights why people with COVID-19 should focus on helping them self-isolate early in the course of their illness. There are four ways to help people self-quarantine:

1. Reducing income to avoid excessive pressure to work when sick (In the UK, 29% of salaries are eligible for sick leave.).
2. Housing for underprivileged communities, especially those who live in crowded homes and those who live with vulnerable people, Vermont, In the United States.
3. A service that supports people who are self-isolated, as is done in New York And many Southeast Asian countries.
4. Remove and consider barriers to access to healthcare Shorten quarantine – 5-7 days after onset of symptoms.. This covers the most infectious periods and may improve the ability of people to adhere to quarantine. In September, France reduced the case isolation period to 7 days, and Germany is considering reducing it to 5 days. The benefits of shortening quarantine can go beyond offsetting risks to the community.

With these measures in place, you can be in a better position to overcome the pandemic.

Huge sevic, Clinical Lecturer, Infectious Diseases and Medical Virology, University of St Andrews And Antonia Ho, Senior clinical lecturer, University of Glasgow

This article will be republished from conversation Under a Creative Commons license.Read Original work..