The United States is currently in the midst of a COVID-19 wave driven by the JN.1 variant, which is causing a surge in hospitalizations and deaths across the country. However, for most people, the new variant does not appear to cause more severe symptoms.
For this reason, many wonder if we should continue taking samples from our nasal passages with coronavirus tests at the first sign of congestion or pain. How effective are rapid home tests against the new variant?
Here’s what you need to know:
Do I still need to get a Covid test?
The flu and some viruses that cause colds circulate along with COVID-19. So there are good reasons to know what virus you have, especially if there is a higher risk of getting very sick.
“It’s important to know if you have COVID-19 or the flu or something that’s not viral at all, like strep throat, because they have different treatments,” said Dr. Abraar Karan, an infectious disease physician at Stanford Medicine. “They have different treatments, and the sooner it is treated, the better the result will be.”
For a healthy 25-year-old, it is still useful to get tested. If someone in the household has a weak immune system or is fighting cancer, for example, it is important to isolate themselves if it is coronavirus.
“Remember that for all of these viruses or bacterial infections, the degree of contagion is different, as is the severity of the disease you can get,” Karan said.
Joseph Petrosino, professor of Molecular Biology and Microbiology at Baylor College of Medicine, acknowledged that while it may not be as necessary for young, healthy people to take a test at home, it can be useful to know if it is COVID-19 in case of someone ending up with long-term symptoms.
“There are healthy people, runners or people who exercise, who also suffer from long-term coronavirus,” he said. “You really never know. “It’s difficult to predict just based on comorbidity factors alone.”
Otherwise, for someone who is low risk, receiving a positive COVID-19 test is not going to change treatment much. Whether it’s coronavirus, a cold, or the flu, you need to get plenty of rest, stay hydrated, and stay away from others.
How does the new variant affect testing?
According to experts, there is no data to indicate that the JN.1 variant influences the results of a rapid home test.
“I haven’t seen anything to suggest that the new variants have evaded detection by testing,” Karan said. “Certainly, that’s happened in the past with other diagnoses early in the pandemic, but right now the tests should detect these variants.”
Susan Butler-Wu, a clinical pathologist at the Keck School of Medicine at the University of Southern California, said that although she has not seen data on this variant, if it is anything like others and it will not be a problem. In reality, rapid tests look for a part of the virus that has less likely to mutate and evade.
“There is always the fear that some mutation will occur that will make the tests not work, but so far that has not been the case,” Butler-Wu said.
What is the best time for testing?
In the early days of the pandemic, before most people had any form of immunity from infection or from vaccines, a person’s viral load was at its peak when symptoms first appeared.
Now, according to a study published last fall in the journal Clinical Infectious Diseases by researchers at Harvard Medical School, virus levels may be higher within days of contracting the disease. They found that in people with existing immunity, the level of virus peaks around the fourth day of symptoms.
This means that if someone gets tested too early in the illness, can be negative.
“Your symptoms could be due to your immune response,” Karan explained. “Having some inflammation causes symptoms, and that’s also stopping the virus from building up very quickly, so your initial test could be negative.”
The Centers for Disease Control and Prevention (CDC) continues to recommend testing immediately if you think you have been exposed to COVID-19 and have symptoms such as congestion, cough, or body aches.
If you have been exposed but do not have symptoms, the CDC recommends that you wait five days.
There is a misconception that rapid testing is “one and done,” Butler-Wu said.
“If you have symptoms and the first test is negative, you have to repeat it,” he explained.
The CDC’s official recommendation is that if you have symptoms, get a rapid test and, if negative, repeat it 48 hours later.
I have tested positive. Am I contagious?
Rapid home tests are a good way to find out if someone is contagious.
Simply put, rapid tests require a higher level of virus to test positive, and higher levels of virus usually mean someone is more contagious.
However, They have some limitations.
Karan stated that although at the beginning of the disease they can be good indicators of contagion, they are not so reliable at the end of it.
There is data where rapid tests came back positive, but when samples were taken from people, the virus could not be cultured, meaning these people were unlikely to be contagious, Karan said.
A 2022 study by researchers at Harvard Medical School suggests that only half of the people that test positive after five days are actually contagious.
“After that period of time, if your rapid test is positive it is no guarantee that you will still be contagious.”
