CHARLOTTE AMALIE — Mutant strains of COVID-19 present the greatest risk of infection to people in the U.S. Virgin Islands because the B117 and the delta variant are at least 50 percent more transmissible than previous versions of coronavirus, health experts warn.
The delta variant (first detected in India in late 2020) already accounts for 95 percent of all new coronavirus cases in the United Kingdom and in April the alpha variant (first detected in the UK and better known as B117) became the dominant strain of COVID-19 in the United States.
“A variant like delta that has more transmissibility will lead to more hospitalizations and more deaths among a population that has low vaccination coverage,” Dr. Henry Walke, director of the CDC’s division of preparedness and emerging infections, said.
Meanwhile, the Virgin Islands Department of Health said this week that twenty-seven additional COVID samples have tested positive for the highly contagious UK variant — a clear indication that the B117 variant is making inroads into the USVI.
“Confirmation is pending until next week, VIDOH said. “Those samples are from cases on St. Thomas and St. Croix.”
Some 19 USVI samples of people who tested positive for coronavirus have been sent to Yale University for further testing to officially confirm that it is the highly-contagious UK COVID-19 strain that is now affecting people here.
“As new positive cases rise amongst unvaccinated individuals, there is a greater chance for the virus to mutate,” the VIDOH said. “These mutations can quickly spread across the islands and are known to be highly contagious.”
The department said Yale University will conduct full scientific sequencing of the samples to determine if it is B117, the British mutation of coronavirus that anticipated the now prevalent “delta variant.”
“B117 is estimated to be 40 percent to 80 percent (with most estimates occupying the middle to higher end of this range) more transmissible than the wild-type SARS-CoV-2, the original strain,” VIDOH said.
“Fortunately, we do not have the Delta strain in the territory yet. It has been identified in Puerto Rico in a traveler,” the health department said. According to the Wall Street Journal, the Delta variant is considerably more transmissible than older strains of the virus and the infection is more likely to result in hospitalization.
What caused COVID-19 to change to a new variant?
All viruses — including SARS-CoV-2, the virus that causes COVID-19 — evolve over time, according to a World Health Organization “explainer.” When a virus replicates or makes copies of itself, it sometimes changes a little bit, which is normal for a virus, WHO said. These changes are called “mutations.” A virus with one or more new mutations is referred to as a “variant” of the original virus.
When a virus is widely circulating in a population and causing many infections, the likelihood of the virus mutating increases. The more opportunities a virus has to spread, the more it replicates – and the more opportunities it has to undergo changes.
Most viral mutations have little to no impact on the virus’s ability to cause infections and disease. But depending on where the changes are located in the virus’s genetic material, they may affect a virus’s properties, such as transmission (for example, it may spread more or less easily) or severity (for example, it may cause more or less severe disease).
The V.I. Health Department said it is monitoring the progress of COVID-19 mutations on neighboring islands as inter-island travel can add to the spread of the virus. Mutations make the virus more virulent and could potentially cause it to be resistant to the vaccine in the future, the department said.
“The sooner more residents get vaccinated, the risk will decrease. It is important for everyone 12 and older to get the COVID-19 vaccine,” VIDOH said.
Relative to the B117 variant first found in London, scientists said the mutation changes the spike protein found on the surface of the virus by increasing its ability to latch onto human cells — allowing the virus to spread much faster than the dominant strain.
“Every mutation buys the virus a lottery ticket. Sometimes that lottery ticket comes up with a mutation which enables it to transmit to more people,” Bill Hanage, an associate professor of epidemiology at the Harvard T.H. Chan School of Public Health, said.
The variant has at least 23 new genetic changes, which is an unusually high number, according to scientists. The spike protein contains amino acids that use furin, a body enzyme that breaks down cell coatings and allows Covid-19 to penetrate.
A number of other strains have since emerged, including one from South Africa named B.1.351, which contains traits similar to the strain first reported in the UK but with another mutation named E484K that isn’t present in the UK variant.
The delta variant of the coronavirus is spreading rapidly in the United States spurred on by local surges that disproportionately affect rural communities and isolated communities.
According to the Wall Street Journal, researchers believe that the E484K mutation has changed the shape of COVID-19’s spike protein, which the virus uses to attach to and infect human cells.
One of the more recent and trending strains, called Delta has been affecting the UK and has caused a delay to the long-awaited easing of COVID-induced restrictions in Britain. However, British data show that vaccines offer somewhat diminished protection against infection with the variant but substantial protection against severe illness, especially after the full two doses, according to the Wall Street Journal.
Almost 80 percent of adults have received at least one dose of vaccine in the UK and 57 percent are fully vaccinated. That compares with 64 percent and 54 percent in the United States, respectively, the newspaper reported.
What impact do the new variants of the COVID-19 virus have on vaccines?
The COVID-19 vaccines that are currently in development or have been approved are expected to provide at least some protection against new virus variants because these vaccines elicit a broad immune response involving a range of antibodies and cells. Therefore, changes or mutations in the virus should not make vaccines completely ineffective. In the event that any of these vaccines prove to be less effective against one or more variants, it will be possible to change the composition of the vaccines to protect against these variants.
Data continues to be collected and analysed on new variants of the COVID-19 virus. WHO is working with researchers, health officials and scientists to understand how these variants affect the virus’s behaviour, including their impact on the effectiveness of vaccines, if any. See WHO’s Disease Outbreak News to get up-to-date information on the impact of COVID-19 virus variants on the effectiveness of the different vaccines. This is an area where the evidence remains preliminary and is developing quickly.
While we are learning more, we need to do everything possible to stop the spread of the virus in order to prevent mutations that may reduce the efficacy of existing vaccines. In addition, manufacturers and the programmes using the vaccines may have to adjust to the evolution of the COVID-19 virus: for example, vaccines may need to incorporate more than one strain when in development, booster shots may be required, and other vaccine changes may be needed. Trials must also be designed and maintained to allow any changes in efficacy to be assessed, and must be of sufficient scale and diversity to enable clear interpretation of results. Studies of the impact of vaccines as they are deployed are also essential in order to understand their impact.
“It’ll play out as sporadic tragedies that are preventable,” said Jeremy Kamil, an associate professor of microbiology and immunology at Louisiana State University Health Shreveport. “It’s unlikely that we’ll see a replay of January 2021 in August 2021, but we’ve already had 600,000 deaths in this country. How much more do we want?”