HILLSBOROUGH COUNTY, Fla. — The World Health Organization classified the B.1.617 COVID-19 strain first identified in India as a variant of global concern. 

At a virtual press conference on Monday, WHO COVID-19 Technical Lead Dr. Maria Van Kerkhove told reporters that teams within the organization have been discussing what they know about this variant for several days. She said early studies show the strain may be more transmissible.

"Even though there is increased transmissibility demonstrated by some preliminary studies, we need much more information about this virus variant in this lineage, in all of the sub lineages," Van Kerkhove said. "We need more sequencing, targeted sequencing to be done and to be shared in India and elsewhere so that we know how much of this virus is circulating."

B.1.617 was first identified in India and scientists say it has branched off into three sub lineages.

"It's one of the three branches, that's actually the variant of concern," said virologist Dr. Michael Teng, an associate professor of medicine with the University of South Florida's College of Medicine.

According to Centers for Disease Control and Prevention data for April 11-24, the most common branch, B.1.617.1, made up just .2% of U.S. cases. Teng said it's hard to say what we'll see in this country, but notes the UK is seeing an exponential increase in cases of the variant.

"Case numbers are coming down, so any increase in percentage is going to magnified by the decrease in numbers, but it is a little concerning that it seems to be transmitting a little better than expected in the UK," Teng said.

Van Kerkhove noted that any circulating strain has the potential to infect, which is why she said it's important to continue taking steps to prevent infection.

The WHO's weekly epidemiological update on the pandemic says the impact of B.1.617 on vaccines and therapeutics remains uncertain.