LOS ANGELES, April 26 (Xinhua) -- A new Omicron subvariant is spreading in the United States and has drawn concern for its high transmissibility and new symptoms.
The subvariant XBB.1.16, referred to as "arcturus", is responsible for 9.6 percent of current COVID-19 cases in the country, up from 5.7 percent the week prior, according to data from the U.S. Centers for Disease Control and Prevention.
Omicron subvariant XBB.1.5 remains the dominant strain in the United States and accounted for 73.6 percent of new COVID-19 cases.
The World Health Organization (WHO) has elevated XBB.1.16 as a new variant of interest. It is a descendant of the recombinant XBB, which is a mashup of two BA.2 sublineages.
XBB.1.16 does have a mutation that makes it a little more transmissible, a little more infectious, said Neha Narula with Stanford Health Care, adding they are seeing an uptick in children.
"When it comes to symptoms we are still seeing things like sore throat, cough, fever, but the new symptom people are talking about is the symptom of conjunctivitis, or as we know it more commonly -- pink eye. It is happening in both children and adults," Narula told CBS.
"With the prior strain we were seeing more colds and fever, cough, headaches even, pink eye wasn't as common. With this particular strain we are seeing this more commonly and in more patients," she said.
The new subvariant has one additional mutation in the spike protein which in lab studies shows increased infectivity as well as potential increased pathogenicity, according to Maria Van Kerkhove, the WHO's COVID-19 technical lead.
Higher levels of infectivity are being reported with newer variants, but overall, they tend to be causing less-severe disease, which is likely the result of higher vaccination rates, higher rates of immunity from previous infection, and lower pathogenicity of recent variants, according to the Mayo Clinic.
The new strain was first detected in January and since then has been discovered in over 30 countries. The WHO is monitoring XBB.1.16, which is contributing to a recent surge of COVID-19 cases in India.
Experts warned the percentage of XBB.1.16 is expected to increase in the United States in the coming weeks, possibly become the next dominant coronavirus strain in the country.
