DHS and Laboratory Partners Identify Variant Strain B.1.351 of SARS-CoV-2 in Wisconsin

On March 4, the Wisconsin Department of Health Services and laboratory partners identified a second variant strain of SARS-CoV-2, the virus that causes COVID-19, in Wisconsin. This variant strain differs from variant B.1.1.7, which was first identified in Wisconsin on January 12, 2021.

The newest variant, referred to as B.1.351, was first discovered to be circulating in South Africa in samples dating back to October 2020. According to epidemiologic and modeling studies, researchers have found that this new strain, similar to B.1.1.7, spreads more rapidly and easily than the original strain of SARS-CoV-2. It is not yet known if this variant has any impact on disease severity. There is some evidence to suggest that this variant may affect how some antibodies respond to the virus. Experts expect that all three currently authorized vaccines effectively reduce the risk of COVID-19 for all of the circulating variants.

In Wisconsin, strain B.1.351 was identified through ongoing surveillance and whole genome sequencing, a routine practice since the onset of the COVID-19 pandemic. All viruses, including the virus that causes COVID-19, change through mutation.

“It is important to remember that new variants are expected to occur over time. Here in Wisconsin, whole genome sequencing of positive specimens from COVID-19 cases is done on a regular basis, said DHS Deputy Secretary Julie Willems Van Dijk. “Because these variants may spread more easily than the original strain of SARS-CoV-2, mask wearing, staying home, physically distancing, and washing your hands continues to be crucial.”

DHS, the Wisconsin State Laboratory of Hygiene, and other laboratory partners regularly work together to ensure whole genome sequencing is performed on a portion of positive tests. DHS also works with clinicians to identify cases that may be good candidates for screening, such as individuals who have traveled internationally. Analysis of genetic sequence data assisted in identifying strain B.1.1.7 and this most recent variant, B.1.351. To date, 26 cases of variant B.1.1.7 and one case of variant B.1.351 have been identified in Wisconsin. Molecular surveillance of SARS-CoV-2 has become increasingly important in order to quickly identify and understand characteristics of these new variants.

With emerging strains of SARS-CoV-2, it is essential to continue public health practices to prevent the spread of COVID-19. Wear a mask when in public, physically distance from others, stay home whenever you can, wash your hands frequently, and get vaccinated when you are able. Vaccine is an important tool to limiting the spread of COVID-19. So far, studies show that the current available vaccines provide protection against new variants, and this is protection is being closely monitored.

For up-to-date information about Wisconsin’s COVID-19 response, visit the DHS COVID-19 webpage. We encourage you to follow @DHSWI on Facebook(link is external), Twitter(link is external), or dhs.wi(link is external) on Instagram for more information on COVID-19.