For most of this year, the JN.1 variant of the coronavirus accounted for the vast majority of coronavirus cases. However, a variant called KP.2 is now becoming popular. The variant, which accounted for just 1% of U.S. cases in mid-March, now accounts for more than a quarter.
KP.2 belongs to a subset of coronavirus variants that scientists have cheekily dubbed “FLiRT,” after the letters in the mutation's name. Dr. David Ho, a virologist at Columbia University, said these are descendants of JN.1 and that KP.2 is “very, very close” to JN.1. However, Dr. Ho conducted early clinical tests using cells and found that slight differences in KP.2's spike protein may increase its ability to evade human immune defenses, making it more capable than JN.1. This suggests that it may be slightly more contagious.
Although the number of cases does not appear to be on the rise, researchers and doctors are watching closely to see whether this variant will cause a summer surge.
“I don't think anyone necessarily expected things to suddenly change,” said Dr. Mark Sala, co-director of Northwestern Medicine's COVID-19 Center in Chicago. But KP.2 will likely “become our new standard,” he said. Here's what you need to know:
Current Covid Spread
Experts say it will take weeks to see if KP.2 will lead to an increase in coronavirus cases, noting there is limited understanding of how the virus is spreading. did. Since the public health emergency ended, there has been less hard data on cases, and doctors said fewer people are using coronavirus tests.
But what we do know is reassuring. Despite changing variants, CDC data shows only “minimal” levels of the virus are circulating in wastewater nationwide, with fewer emergency department visits and hospitalizations from early March to April. It decreased towards the end of the year.
“We don't want to say we already know everything about KP.2,” said Dr. Ziyad Al Ali, director of research and development at the Department of Veterans Affairs St. Louis Health System. “But at this point, there are no signs of anything ominous.”
Protection from vaccines and past infections
Experts say that even if you have been infected with JN.1, you can be reinfected with KP.2, especially if it has been more than a few months since your last infection with the coronavirus. Ta.
KP.2 targets XBB.1.5, a variant that is markedly different from JN.1 and its descendants, so even people who have received the latest vaccines can be infected, Dr. Ho said. An early version of a paper published by Japanese researchers in April suggested that KP.2 may be more adept than JN.1 at infecting people vaccinated with the latest coronavirus vaccine. Ta. (The study has not yet been peer-reviewed or published.) A CDC spokesperson said the agency continues to monitor how well the vaccine performs against KP.2.
Still, as with previous infectious diseases, doctors said the vaccine offers some protection, especially against severe disease. At this time, there is no reason to believe that KP.2 causes more severe illness than other strains, a CDC spokesperson said. However, people over 65, pregnant, or immunocompromised are still at higher risk of serious complications from the coronavirus.
Dr. Peter Chin-Hong, an infectious disease expert at the University of California, San Francisco, said these groups may be especially willing to get vaccinated if they don't already have the latest vaccines. The CDC recommends that people 65 and older who have already received one dose of the latest vaccine receive a booster shot at least four months later.
“Even though deaths and hospitalizations are at an all-time low, I am still caring for patients with COVID-19,” he said. “And they all have one unifying theme: They're older and haven't had their latest shots.”
Latest information on symptoms and long-lasting coronavirus
Doctors said the symptoms of both KP.2 and JN.1, which currently account for about 16 percent of cases, are similar to those seen with other variants. These include sore throat, runny nose, cough, head and body aches, fever, congestion, fatigue, and in severe cases, shortness of breath. Although fewer people are now losing their sense of taste or smell than at the beginning of the pandemic, some people may still experience these symptoms.
Dr Chin-Hong said patients are often surprised to learn that diarrhea, nausea and vomiting can also be symptoms of coronavirus, and can confuse these problems with signs of norovirus infection.
For many people who have already had coronavirus, reinfection is often as severe or milder than the initial infection. Fikadou Tafesse, a virologist at Oregon Health and Science University, said new cases of COVID-19 are less common now than they were at the beginning of the pandemic, but repeated infections can lead to COVID-19. He said there is an increased risk of But researchers are still trying to determine how much, and this is one of many questions scientists are trying to answer as the pandemic continues to evolve.
“That's the nature of viruses,” Dr. Tafesse says. “It keeps mutating.”
