A COVID-19 mutant named KP.2 has now replaced JN.1 as the main epidemic strain in the United States, and KP.2 is the descendant pedigree of Omicron mutant JN.1.
COVID-19 added new variants. According to the data released by the U.S. Centers for Disease Control and Prevention (CDC) on May 10, a COVID-19 mutant named KP.2 has now replaced JN.1 as the main epidemic strain in the United States. However, the latest April data released by the Chinese Center for Disease Control and Prevention shows that the variant has not yet spread domestically.
According to the latest data released by the US CDC on Friday, the KP.2 mutant accounted for 28% of the COVID-19 infection in the US in the two weeks up to May 11, and only 6% in mid April.
The COVID-19 KP.2 variant was detected in the sewers of the United States in March this year, accounting for only 1% of COVID-19 infection cases at that time, and has spread rapidly since then. In early May, the World Health Organization (WHO) listed KP.2 subspecies as a variant under monitoring. Maria Van Kerkhove, technical director of COVID-19, WHO, said earlier that KP.2 is the descendant pedigree of the Omikjon variant JN.1, which is currently the main epidemic strain in the world, and KP.2 spike protein has additional mutations.
However, as of now, there are no signs of KP.2 variant transmission in China. According to the latest data released by CDC, from April 1 to April 30, 2024, 31 provinces (autonomous regions, municipalities directly under the Central Government) and Xinjiang Production and Construction Corps reported 11299 valid genome sequences of COVID-19, all of which are Omikron variants, from local cases. The main prevalent strains are the JN.1 series variant strains, with the top three being JN.1, JN.4, and JN.16, respectively.
The World Health Organization has stated that as JN.1 continues to mutate, new variants will emerge and the virus’s evolution will continue to be closely monitored.
Some scientists collectively refer to KP.2 and another variant called KP.1.1 as “FLiRT”, which share the same key mutation, but KP.1.1 does not spread as quickly as KP.2. Infectious disease experts suggest that additional mutations may make it easier for the virus to bypass the immune protection provided by vaccines or previous infections.
According to a preprint study conducted by a Japanese laboratory, the protective effect of the current COVID-19 vaccine in the United States against KP.2 may not be as good as that against JN.1. But this study also suggests that the efficiency of KP.2 in infecting cells may be lower, which means higher doses of the virus are needed to infect humans.
COVID-19 is still mutating, which also brings new challenges to vaccination decision-making. Last week, the US Food and Drug Administration (FDA) postponed an advisory committee meeting that was originally scheduled to decide on the vaccine version for autumn updates.
The spokesman of the US FDA said that since the major epidemic strains of COVID-19 had recently been observed to have changed, additional time was needed to obtain more new monitoring data on COVID-19 epidemic strains, so as to better provide information for the discussion and recommendations of the Committee.
According to the US Centers for Disease Control and Prevention, only a quarter of American adults have received the updated COVID-19 booster vaccine. Against the background of the sudden drop in vaccine demand, AstraZeneca said last week that it would stop the production and sales of COVID-19 vaccine globally.
Nevertheless, some vaccine giants still haven’t stopped the research and development work related to COVID-19 vaccine. On May 10 local time, Sanofi, a French pharmaceutical company, and Novavax, an American vaccine company, announced that they had reached a joint exclusive licensing agreement to jointly commercialize COVID-19 vaccine and develop new influenza and COVID-19 joint vaccine.