How can we stop the winter “triple” respiratory viruses from ruining the upcoming holiday trip and family gatherings? People know when they have it covid symptoms, But does a small sneeze at the end of the corona virus, for example, mean it’s still contagious?
So many covid questions!
It’s a good time to learn what scientists know and still don’t know about how often people get sick from viral diseases — Covid, influenza, RSV — that are spreading across the US.
How long will I have covid?
If you are exposed to someone who tests positive for Covid, symptoms of any of the Omicron subtypes generally appear after two to four days.
How contagious you are is related to how much virus is in your body, known as viral load. According to Dr. Chanu Ray, a professor of medicine at Harvard Medical School, your viral load can peak after the onset of symptoms. This means they can be highly contagious the day before symptoms appear and at least for the first two or three days.
Your infectiousness will decrease over time as your immune system reduces your viral load.
“If people are still very, very symptomatic, have a lot of coughing and a lot of upper respiratory infections, they’re probably more contagious,” Dr. Lisa said. Harvard Medical School infectious disease expert A. Cosimi.
But it can be difficult to determine whether you are somewhat contagious in the days when the number of cases of Covid is declining.
of Centers for Disease Control and Prevention It recommends that people experiencing moderate to severe symptoms self-isolate for 10 days. If you have mild Covid, to protect others, consider yourself contagious for at least five days from the time symptoms appear, or five days after you test positive, which is considered day zero, the CDC recommends.
A study of 66 people with severe covid disease Published In July, the New England Journal of Medicine reported that the median time until the participants were infectious was six days during the peak of the delta variant of the virus and eight days during the omicron wave.
as one October study Among 4,565 people infected with Covid, he said: “Overall, current data suggest that infectiousness beyond 10 days (using viral culture as a proxy) is rare but possible.”
The investigators called for more research on whether people remain contagious after this point.
However, various infectious disease experts report that there are cases of immunocompromised people who have been contagious for months.
As far as relying on covid tests to determine if a person is still contagious, PCR tests are good at diagnosing covid. They are not reliable for determining persistent infectivity, as they detect harmless fragments of the virus for weeks or months after infection.
Rapid at-home antigen tests are also imperfect. Researchers test whether they can grow the virus in the lab by taking a sample of the coronavirus, known as viral culture tests, which are the best proxy for infectious diseases. But everyday people don’t have access to such challenges.
In the near future Research Three-quarters of the 40 people who tested positive for Covid-19 tested positive within six days of their first test or the onset of symptoms.
As part of the study, participants received tests known as virus culture, where scientists see if they can grow the virus taken from a swab in the lab. It is considered the best proxy for infectious diseases.
At that time, about half of the group had a negative viral culture test, indicating that they were not infectious.
Cosimi, an infectious disease expert at Harvard Medical School who led the study, said that after five days of covid — if people test negative when they get better and still have lingering symptoms — they probably aren’t contagious.
He also said that if immunocompromised people feel better on day 11 but still test positive on an antigen test, it is “highly unlikely” they are still contagious.
According to the CDC, if you are symptom-free after five days, or if your Covid symptoms are improving and you have not had a fever for 24 hours, you can end your isolation period.
You can go out for six to 10 days, but you have to wear a mask.
You don’t need to try to end your isolation period in these contexts. The CDC says you can take off the mask early if you test negative on two consecutive rapid antigen tests 48 hours apart.
There is a condition though.
“You still have to wear a mask until day 10 because theoretically you’re still contagious, even if your level of infection is reduced,” Ray said.
How often is it contagious? Did I get covid or am I fully vaccinated and got the infection?
Most of the studies, however, looked at patients affected by the older variants, Rhee said.
“The effect of early immunity on infectious diseases is unclear for omicron variants.”
On average, unvaccinated people take longer to overcome infection, said Dr. Jonathan H. Grad, associate professor of immunology and infectious diseases at the Harvard T.H. Chan School of Public Health and senior author of a recent article in the journal eLife. He and his colleagues came to this conclusion.
“We don’t know about the duration. Contagion” Grad said in an email.
Am I contagious if I am taking Paxlovide?
Research Published In July, taking paxolovide in clinical infectious diseases accelerated the clearance of the corona virus, which the authors said could reduce the infection.
The latest Research It has raised doubts about whether paxlovide is driving cases of viral rebound, because people who don’t take paxlovide also relapse.
“What we don’t know is whether or not those resets are contagious,” said Dr. Donald Milton, a professor of environmental and occupational health at the University of Maryland.
Therefore, CDC recommends restarting the isolation clock at day zero if a rebound occurs.
How long will I catch the flu or other viral illnesses?
With colds, RSV (respiratory syncytial virus), and the flu, people generally get sick a day or two before and a few days after the onset of symptoms.
The CDC recommends that people with the flu stay home for at least 24 hours without using fever-reducing medications or until the fever subsides after their symptoms improve — at least four to five days after getting sick.
2010 Research He identified a link between a reduction in influenza symptoms, particularly fever, and a reduction in viral shedding, which indicates infectivity.
“If you’re really sick, if you have a fever, you can be contagious for a little bit longer,” said Aubrey Gordon, an associate professor of epidemiology at the Michigan School of Public Health. “The level of symptoms can be a guide to when you need to stay at home. But that doesn’t mean mild symptoms aren’t contagious.
Classic common cold symptoms include congestion, cough, runny nose and low-grade fever. some Cold symptoms can last from 10 to 14 daysAccording to the CDC.
For the flu – which can include RSV in adults, a virus that can pose a serious threat to children under 2 – Dr David Strain, senior clinical lecturer at the University of Exeter Medical School, said: “It’s mostly you. It’s only contagious as long as you have symptoms.
This article was originally published by NBCNews.com