Way back in January of this year, which feels a lifetime ago now, we published an article on the B.1.1.7 variant, first identified in the U.K., and which now accounts for about 26 percent of all U.S. infections, according to recent CDC estimates. I suggested in the article that by June of this year, or possibly earlier, B.1.1.7 would be the dominant strain of SARS-CoV2 in the US. I also warned that taking our eye off the ball would lead to another spike. Here we are.
According to Rochelle Walensky, MD, CDC director, the B.1.1.7 variant is already the dominant strain in at least five regions in the US. Little wonder when you see how transmissible the strain is. Between and 50 and 70% more than the original strain and as we’ve come to expect, all the usual suspects (Florida, Texas, and Michigan) are reporting worrying trends in hospitalization in recent days, cases involving the variants. You can use the CDC link below to access a mapping tool that will allow you to check the levels of variants in your area. The tool can be found here and includes data and figures. (see screenshot)
At the moment the CDC lists five “variants of concern.” These are defined as ones
“for which there is evidence of an increase in transmissibility, more severe disease (increased hospitalizations or deaths), a significant reduction in neutralization by antibodies generated during previous infection or vaccination, reduced effectiveness of treatments or vaccines, or diagnostic detection failures.”
The CDC uses a three-tier classification system to establish a risk profile for each variant. There are no variants yet classified under the most serious listing.
- “variant of high consequence” as the most worrisome group,
- “variant of concern” and then
- “variant of interest.”
The CDC has provided the following information on each of the know variants.
B.1.1.7, first detected in the U.K.:
- About 50 percent more transmissible
- Likely causes increased disease severity based on hospitalizations and case fatality rates
- Minimal effect on neutralization by monoclonal antibody therapeutics authorized by the FDA for emergency use
- Minimal effect on neutralization by antibodies generated during previous infection or vaccination
- The U.S. has reported 12,505 cases of this variant as of April 1, with Florida (2,351), Michigan (1,237) and Colorado (894) recording the highest number of cases.
P.1, first detected in Brazil and Japan:
- No information provided regarding transmission
- No information provided regarding disease severity
- Moderate effect on neutralization by monoclonal antibody therapeutics authorized by the FDA for emergency use
- No information provided regarding the effects of past infection or vaccination
- The U.S. has reported 323 cases of this variant as of April 1.
B.1.351, first detected in South Africa:
- About 50 percent more transmissible
- No information provided regarding disease severity
- Moderate effect on neutralization by monoclonal antibody therapeutics authorized by the FDA for emergency use
- Moderate reduction in neutralization by antibodies generated during previous infection or vaccination
- The U.S. has reported 224 cases of this variant as of April 1.
B.1.427, first detected in California:
- About 20 percent more transmissible
- No information provided regarding disease severity
- Significant effect on neutralization by some, but not all, therapeutics authorized by the FDA for emergency use
- Moderate reduction in neutralization by antibodies generated during previous infection or vaccination
- The CDC is not yet providing national case counts for this variant.
B.1.429, first detected in California:
- About 20 percent more transmissible
- No information provided regarding disease severity
- Significant effect on neutralization by some, but not all, therapeutics authorized by the FDA for emergency use
- Moderate reduction in neutralization by antibodies generated during previous infection or vaccination
- The CDC is not yet providing national case counts for this variant.
