May 20, 2:30 pm: This story has been updated to reflect new information from Dallas County that the two cases are in children younger than 12.
Two cases of a coronavirus variant that has spread catastrophically in India have been detected in the Dallas area for the first time, researchers at UT Southwestern Medical Center told The Dallas Morning News on Wednesday.
The virus, which the World Health Organization dubbed a variant of concern last week, appears to be more contagious than older coronavirus variants. It also carries mutations that help it evade human antibodies, although early testing shows that vaccines remain effective against it.
The samples were picked up by UT Southwestern researchers, who began to genetically analyze samples from coronavirus patients earlier this year.
The two Dallas-area cases are in children younger than 12 who are not yet eligible to be vaccinated. They have no recent travel history, said a Dallas County spokesperson. No further information was available about the patients at press time.
“The presence of these variants emphasizes the importance of getting vaccinated to help protect yourself, because these variants are increasingly showing that they’re able to spread more easily,” said Dr. James Cutrell, an infectious disease expert at UT Southwestern.
The variant, dubbed B.1.617.2, was first identified in India in December. Since then, it has become a dominant source of infection in the country, although it’s unclear to what extent the virus is driving the pandemic compared to other factors such as large gatherings and low vaccination rates.
The B.1.617.2 variant has also spread rapidly in the United Kingdom, threatening to derail that country’s planned June 21 reopening. British officials said they would have more data on the variant’s transmissibility in the coming days.
Its spread in the U.K. has U.S. experts on alert. They say B.1.617.2 may follow a similar trajectory to B.1.1.7, the variant first detected in the U.K. last year. The B.1.1.7 variant is now the dominant source of coronavirus infections in the U.S. and the U.K.
“If you look at the B.1.1.7 variant, basically what transpired in the U.S. was more or less identical to what transpired in the U.K.,” said Dr. James Musser of Houston Methodist Hospital, whose team has sequenced and analyzed thousands of coronavirus samples.
His team has detected seven cases of variants first identified in India, including B.1.617.2 and the closely related sub-lineage B.1.617.1 in his Houston hospital system since March. He said it’s too early to know whether the family of variants would become more dominant.
According to the Centers for Disease Control and Prevention, B.1.617.2 accounts for around 1% of all coronavirus cases in the U.S.
The arrival of the B.1.617 family of variants highlights the importance of genetic sequencing, which the CDC has been working to scale up in the U.S., experts said.
Because variants have different rates of transmission, identifying them early is important for accurate disease modeling and projections, which in turn helps health care officials better prepare for possible surges.
“One of the things that we’ll be watching very closely over the next week, the next month, is: Does this variant remain in the minority, or does it start to overtake some of the other variants and become more dominant?” said Cutrell. “If we see that, then that’s the way that we pick up on clues that there’s something different about this virus in terms of how easily it’s spread.”
