BA.5 is currently the dominant strain of COVID-19 in the U.S. Here’s what you need to know about this latest COVID variant and how to best stay protected.
What Is the BA.5 COVID Variant?
BA.5 is one of the newest sub-variants of the COVID-19 Omicron virus. It made up 85.5% of all COVID cases in the U.S. between July 24 and July 30, reports the CDC. At present, the three most common variants of Omicron are BA.2, BA.4, and BA.5.
How Is BA.5 Different From Other Strains of COVID?
The BA.5 variant currently represents the highest number of COVID cases, and therefore may be more contagious than other strains of this disease. It also appears to “evade protection from vaccines and previous infections more easily” than previous variants, according to a report from NBC News.
David Montefiori, a professor at the Human Vaccine Institute at Duke University Medical Center, says BA.5 is approximately three times less sensitive to neutralizing antibodies from COVID vaccines than the original version of Omicron. It is also four times more resistant to antibodies from COVID vaccines than BA.2, according to a recent study published in the journal Nature.
In June, the U.K. reported that the majority of people who were testing positive for COVID were experiencing symptoms including fever, abdominal pain, sore throat, and muscle aches. BA.5 and BA.4 accounted for the majority of new COVID cases in the U.K. during that time.
It added that the percentage of people experiencing these symptoms was far greater in June than it was in May. During the last week of June, the most common COVID symptoms reported were runny nose, sore throat, headache, cough, and fatigue. Fevers affected fewer than one-third of the people surveyed.
BA.5 Spread and Reinfection Rates: What Data Is Available?
Francois Balloux, the director of the University College London Genetics Institute, says BA.5 and other recent COVID variants are equally transmissible. Montefiori adds that BA.5 hasn’t been shown to cause more severe disease than other variants. However, a newer report published in Reuters on July 28 says that reinfections and severe outcomes may be more common with the BA.5 strain. Additionally, BA.5 is more likely to cause COVID reinfection regardless of vaccination status.
Reuters cites a study that ran from late April to early June, during which researchers evaluated a large number of adults infected with either BA.2 or BA.5. They found that 10% of people with BA.5 had been reinfected compared with 5.6% of people with BA.2. Furthermore, COVID vaccines were shown to be less effective in reducing the risk for severe outcomes for BA.5 than they were for BA.2.
The spread of the BA.5 variant can be accurately measured by health departments across the U.S. by using a wastewater surveillance system. According to the CDC, wastewater surveillance can provide communities with an early warning of COVID-19’s spread so they can implement the necessary safety measures, such as encouraging people to get vaccinated. People who want specific data regarding the spread of BA.5 in their communities can contact their local health department or municipal water provider to learn more.
Do the Existing COVID Vaccines Offer Protection Against BA.5?
COVID booster vaccination may reduce the risk of hospitalization and death associated with infection. According to new medical research published on medRxiv that has yet to be peer-reviewed, COVID booster vaccines were associated with a 77% and 88% reduction in the risk of hospitalization and death among those infected with BA.5.
In an initiative to target the BA.5 variant in early fall, the Biden administration announced it is purchasing 66 million doses of a Moderna COVID-19 vaccine that has been updated to offer protection against the new strain. The administration has already ordered 105 million doses of Pfizer’s updated version of the vaccine and says it will be working with state and local healthcare partners to make both the Moderna and Pfizer vaccines available for free in U.S. communities this fall.
Points to Keep in Mind Surrounding COVID
Like the flu, COVID is expected to have many ever-changing strains and variants. Information about COVID and its variants is always evolving as researchers continue to study these strains and learn more about their spread and reinfection rates.
Keep in mind that protection from most vaccines decreases over time — including that from COVID vaccines and boosters. Research already shows that the Omicron BA.5 variant has the ability to evade protection, which is why the Biden administration is encouraging people to receive the updated COVID vaccines in the fall.
According to CBS News, rapid at-home COVID tests may be more effective at detecting BA.5 than those administered at healthcare facilities. Visit COVID.gov to order free at-home COVID tests if you are interested in having yourself and your family tested.
Research and materials for this article were compiled, written, and distributed on behalf of the National Public Health Information Coalition. The views and opinions expressed in this blog are those of the various authors and do not necessarily reflect the official policy or position of the National Public Health Information Coalition or its members.
Centers for Disease Control and Prevention. (n.d.) COVID data tracker.
Bendix A. (2022, July 6). BA.5, now dominant U.S. variant, may pose the biggest threat to immune protection yet.
Wang W, Guo Y, Iketani S, et al. (2022, July 5). Antibody evasion by SARS-CoV-2 Omicron subvariants BA.2.12.1, BA.4, & BA.5.
Office for National Statistics. (2022, August 5). Coronavirus (COVID-19) latest insights: Infections.
Lapid N. (2022, July 28). Reinfection, severe outcome more common with BA.5 variant; virus spike protein toxic to heart cells.
Centers for Disease Control and Prevention. (2022, March 21). National Wastewater Surveillance System (NWSS).
Kislaya I, Casaca P, Borges V, et al. (2022, July 25). SARS-CoV-2 BA.5 vaccine breakthrough risk and severity compared with BA.2: a case-case and cohort study using electronic health records in Portugal.
Tin A. (2022, July 27). How is the BA.5 COVID-19 variant different from other strains?
Department of Health and Human Services. (n.d.) Get free at-home COVID-19 tests.