This dilemma has been faced by many Americans during the pandemic. Yet, it keeps coming up again and again. This is particularly true if you feel better but are still positive for COVID-19.
Even though there have been new subvariants, the fundamental rules of the game haven’t changed. The Centers for Disease Control and Prevention states that someone can stop isolating after five consecutive days if they are fever-free for 24 hrs and feel better aEUR” for five more days. As long as they continue to wear a mask for five more days.
These rules have been criticized by some researchers, citing research that suggests some people can remain infected after five days. Experts recommend waiting to test negative at home before you go out.
However, if you feel good, it can be frustrating for you to wait. This is especially true if your test results are within the past 10 days.
James Hay, an infectious disease researcher, recalls the time his sister tested positive for two more weeks earlier in the year. Their family planned to gather over the holiday “aEUR”, which included an older relative, who was susceptible to COVID.
Hay, a Harvard T.H. Research Fellow, says, “That was just not worth it.” Chan School of Public Health. “Using a mask to go shopping is a different risk assessment.”
It is tempting to try to escape isolation because it promises an easy answer. Unfortunately, aEUR” and perhaps not surprising aEUR”, the science is still not fully settled.
Dr. Emily Landon is an infectious disease specialist at UChicago Medicine. She says, “We don’t have anything that proves you are contagious” These rapid antigen tests are the best we have.
Rapid antigen tests are different from PCR tests which look for genetic material. They instead search for proteins inside the virus. A positive test is usually indicative of the presence or potential spread of an infectious virus. Scientists can test for the presence of infectious virus by taking samples from infected people and then trying to cultivate it in a laboratory. This is known as a viral culture.
Most people who become infected do not test positive for antigens 10 days after symptoms begin.
Hay says, “If your body has enough virus to make one of these tests positive it means that your body isn’t yet completely cleared of the infection.”
However, there are no definitive studies that show how likely it is for a positive rapid test to translate into the possibility of infecting another person. Dr. Geoffrey Baird is the chair of the laboratory medicine and pathology department at the University of Washington School of Medicine.
He says, “The answer is clear as water.”
Infectious disease experts differ on how much stock to take to get a quick test result when someone is infected.
Baird points to the fact that these tests weren’t meant to be used as isolation cards. He says that relying on the test results to determine if you are still infected is dangerous.
He says, “There is actually a lot of discrepancy than anyone would like with.”
Baird says that a positive antigen test could be essentially detecting leftover virus “garbage”. This can include dead viruses, mangled or virulent viruses and viruses that are “90% packed together but not going to work.” The amount of infection can vary according to the person’s immune system, the variants and the stage.
Baird didn’t bother to take a quick test for COVID when he was recently diagnosed. He had to decide when it was okay to return to work. He felt better after a week and returned to work, where everyone must wear an N95 mask.
Even though it’s not perfect, not everyone dislikes the rapid antigen test.
Landon states that it is extra information that can help you make a decision. This is especially important if people rely on the CDC guidance for how to end isolation. She says that some people may still be infected after five days.
Landon co-authored a study that examined health care workers at University of Chicago who were infected, but felt generally better. They went to be tested after five days. After six days, more than half of the participants tested positive for antigens.
This is consistent with other research. One study that examined data from San Francisco’s January omicron surge testing sites found that many people still tested positive five days later. The CDC also found that about half of those tested positive for the antigen test were still positive after five to nine days following diagnosis or symptom onset.
She says, “It would be prudent to follow the test and say, ‘I don’t want to leave my isolation until my test is negative.'”
Scientists at Harvard and MIT have preliminary data that shows about 25% of patients with COVID-19 were symptomatic. The virus could be cultured within eight days following onset of symptoms or the first test.
Hay warns that there are many variables in these studies, including small sample sizes, different populations, how rapid tests are performed, who is being tested, and how well they are vaccinated.
He says, “This explains a lot about the variation across studies but I think it’s still fairly consistent as an overall finding, that if your antigen is positive, then you are quite likely to become infectious.”
Some research aligns more closely with the CDC isolation guidelines, which assumes that most people will not become infected after five days. Preprint studies of nearly 100 college students vaccinated at Boston University suggest that most were not infected after five days.
Dr. Karen Jacobson from Boston University School of Medicine, one of the authors of the study, says that only 17% of patients we examined still had viable COVID after five days. Very few people had virus that could be cultured after symptoms onset.
According to her study, a negative rapid antibody test on day 5 is a good indicator that the virus can be cultured in a laboratory. This means that anyone with a negative rapid antigen test on day 5 or more after initial diagnosis was not likely to have any further detectable virus.
Jacobsen says, “The flip side was the fact that half of those who had positive rapid tests still had culturable viruses.” “If you are positive, this is something we have started to frame, and I believe many others do as well.
The final decision about whether you want to travel the world is down to your context. Landon suggests that you think twice before spending time with high-risk people.
She says, “If you’re thinking of going to the nursing home to see your grandmother, now is not the right time.”
If you have an urgent task, don’t be afraid to leave your home. She suggests that you go for it, but she advises that you keep your mask on.
