A new Covid variant from China called NB.1.8.1 is spreading rapidly in California, health officials have warned. This strain is highly contagious and has been detected in several US states, causing concern among medical experts. The California Department of Public Health confirmed the presence of NB.1.8.1 this week, marking California as the sixth state in the US where the variant has been found.
Since March, the variant has appeared in travelers arriving in Washington, Virginia, Hawaii, Rhode Island, and New York City. Data shows that NB.1.8.1 was first detected in March and has been increasing steadily, especially since May 1. In California, the variant’s share of Covid cases rose from 2 percent in April to 19 percent recently. This increase suggests that the variant could lead to more infections and hospitalizations.
Laboratory tests indicate that NB.1.8.1, first identified in China in January, spreads faster than the Covid strains currently circulating in the US. The World Health Organization reports that NB.1.8.1 now makes up over half of all Covid cases worldwide. Some doctors in California are urging officials to bring back mask mandates to help control the virus, similar to measures taken in places like Hong Kong.
The California Department of Public Health said that Covid continues to circulate and future seasonal rises in cases are likely. While NB.1.8.1 is spreading, it is not yet common enough in the US to be officially tracked by the CDC. The dominant strain in the US remains LP.8.1, which accounts for 73 percent of infections. Current vaccines target the JN.1 variant, a predecessor of LP.8.1, and officials believe these vaccines still offer protection.
There have been recent policy changes as well. Health Secretary Robert F. Kennedy Jr. has moved to restrict access to the Covid vaccine for healthy children and pregnant women, though the CDC still includes the vaccine in its recommended schedule for children. In California, Covid test positivity rates stood at 2.1 percent as of April 19, which is consistent with previous weeks. Hospitalizations were slightly down, with 1.3 per 100,000 people hospitalized, compared to 1.6 the week before.
Across the US, test positivity dropped from 2.9 percent on May 17 to 2.7 percent by May 24. Emergency room visits related to Covid also fell by 6.5 percent in that period. However, in China, the number of seriously ill respiratory patients with Covid increased from 3.3 to 6.3 percent over the past month. The proportion of emergency room patients testing positive jumped from 7.5 to 16.2 percent.
Taiwan has reported a 78 percent increase in Covid emergency room admissions in the week leading up to May 3. Hong Kong is facing its highest hospital admission rate in a year, which health experts link to the new NB.1.8.1 variant. Symptoms of this variant include fever, chills, cough, shortness of breath, fatigue, muscle aches, headache, loss of taste or smell, sore throat, congestion, nausea, vomiting, and diarrhea.