Taking a deeper look at the types of COVID viruses circulating in some hospital patients, researchers at the University of Miami’s Miller School of Medicine have identified a scattering of genetic footprints, with one viral culprit out-competing the others and surging to become the predominant strain.
That version of the virus, called B.1.1.7, or the “U.K. variant,” has been in Florida since late last year, scientists agree, and is destined to become the main strain here, perhaps as soon as this month.
Researchers at UM examined nearly 500 samples of the COVID virus, the bulk of them from patients at Miami-Dade County’s Jackson Health public hospital facilities, and found that B.1.1.7 caused more than 25% of the infections. The U.K. variant is thought to be more infectious but not genetically distinct enough from the original virus to cause concerns about vaccines not working.
But the team also identified more troublesome variants, including three samples of a COVID virus first identified in Brazil that contains the same mutation as a South African variant that derailed the AstraZeneca-Oxford vaccine trial in that country.
They discovered rare variants first sequenced in Saudi Arabia, Aruba and Israel, as well as domestically identified strains — two samples of the California variant, and one sample of a strain first identified in New York.
“Our first couple of sequencing runs, we were surprised to see such a diverse array,” said Dr. David Andrews, a pathologist and University of Miami professor who is leading the research. “ ... We found the two California variants right away.”
Somewhat reassuring is that the most concerning version of the virus, the Brazilian variant, or P1, is being detected at what Andrews called “a very low prevalence.”
Researchers in Brazil and scientists from Imperial College London have recently suggested that the strain that took off in the Brazilian city of Manaus over the winter was spurred on largely by reinfections, and may be more transmissible.
Five cases of that variant have been confirmed in Florida so far, and the U.S. Centers for Disease Control and Prevention added one case of the South African variant on Monday.
Listen to today's top stories from the Miami Herald:
Florida an incubator for COVID variants
Florida has for several weeks led the country in confirmed cases of the U.K. variant, about 600, or 25% of the country’s 2,400 confirmed cases, according to the CDC.
But the real number of cases caused by the U.K. variant is likely much higher, about 25% to 30% of new cases in Florida, according to projections from the private commercial lab, Helix. Those estimates are in line with the findings from UM in hospital patients.
“We know from the experience in the U.K. that this variant is more readily transmissible from person to person, so it is very concerning,” said Mary Jo Trepka, an infectious disease epidemiologist at Florida International University.
Trepka said that competitive advantage explains why it’s been discovered in such high numbers in local hospital patients, despite decreasing cases.
“I think that people are losing track of the fact that [cases] are coming down, but they’re not nearly as low as they were in the fall,” Trepka said. “We still have a very high level of COVID-19 in the community.”
Just as Florida has led the country in variants of the COVID virus, South Florida has led the state. The region also has the highest population density, but its international travel patterns have raised concerns, particularly the Brazilian variant.
Trepka said that travel patterns from tourists and residents alike could be contributing to the concentration of COVID virus variants in Miami.
“Under no circumstances are we an isolated community, quite the opposite,” Trepka said. “Other places in Florida don’t have near the number of international visitors.”
El Nuevo Herald Staff writer Ana Claudia Chacin contributed to this report.