Here’s what you need to know:
- What are BA.4 and BA.5? BA.4 and BA.5 are subvariants of the omicron variant of COVID-19. In other words, they are new mutant versions of omicron. The CDC lists omicron as a variant of concern.
- What is a concern variant? The CDC defines a COV as “a variant for which there is evidence of increased transmissibility, more severe disease (e.g., increased hospitalizations or deaths), significantly reduced neutralization by antibodies generated during previous infection or vaccination, reduced efficacy of treatments or vaccines, or diagnostic detection failures. In other words, a COV is a version of COVID-19 that is found to be more contagious, virulent, or deadly.
- Are BA.4 and BA.5 more transmissible and cause more severe disease? Currently, scientists believe the answer is yes, the subvariants are more transmissible, but no, they do not cause more severe disease. According MedPageToday“The bottom line is that BA.4 and BA.5 are very highly transmissible, cause little serious disease, and are responsive to boosters (although protection wanes), monoclonal antibodies, and antivirals.”
- If BA.4 and BA.5 cause mild illness, why do people care? Because even though a virus can cause mild illness in most people, there are still groups of people where it can cause severe illness and even death. And since transmissibility is high, that means more people could become infected, which means an increase in a proportion of those who will experience serious illness or death. Additionally, public health researchers are increasingly concerned about the long-term impacts of “long COVID,” about which little is yet known.
- What is the extent of BA.4 and BA.5 in America? According to CDC data, as of June 4, BA.4 represents about 5.4% of the total number of cases in the United States. BA.5 represents approximately 7.6% of cases. This means that together BA.4 and BA.5 account for 13% of all cases – and this percentage is growing. (Note that these percentages are based on the agency’s Nowcast tool and are subject to change with future estimates.)
Some parts of the country have higher BA.4 and BA.5 rates than others. Here’s what the rates look like according to the CDC across the country:
- New York/New Jersey area: BA.4 represents 2% of cases. BA.5 represents 4% of cases.
- Upper North-East: Includes states such as Massachusetts and Maine. BA.4 represents 4.4% of cases. BA.5 represents 2.8% of cases.
- Western coast: Includes California, Washington and Oregon. BA.4 accounts for 6.3% of cases in California and 4.1% of cases in Washington and Oregon. BA.5 accounts for 6.8% of cases in California and 11.7% of cases in Washington and Oregon.
- South East : Includes states such as North Carolina and South Carolina. BA.4 accounts for 6.9% of cases. BA.5 represents 3.3% of cases.
- Central South: Includes states like Texas and New Mexico. BA.4 represents 8.9% of cases. BA.5 represents 13.2% of cases.
- South: Includes states such as Florida and Alabama. BA.4 represents 3.9% of cases. BA.5 represents 9.1% of cases.
You can check out the latest CDC Nowcast map here.