A variant is a new strain of the SARS-CoV-2 virus, the virus that causes COVID-19. Variants occur through mutations, which are changes in the genetic code of a virus. Variants have specific gene mutations that make them unique and different from the original SARS-CoV-2 virus. Viruses, including SARS-CoV-2, naturally change or mutate over time and the new variants are expected to occur.
As new variants are expected to occur overtime, this webpage will be updated as we learn more about emerging SARS-CoV-2 variants in Wisconsin.
*Numbers in this dashboard were updated ahead of our scheduled weekly updates because a new variant strain (P.1) and second case of (B.1.351) were identified.
SARS-CoV-2: Total Number Sequenced
|Variant B.1.1.7||Variant B.1.351||Variant P.1|
This chart shows the total number of specimens that have been sequenced using whole genome sequencing by laboratories in the state of Wisconsin. The Wisconsin State Laboratory of Hygiene, along with other laboratory partners, uses data from whole genome sequencing to detect variant cases of SARS-CoV-2, the virus that causes COVID-19. This sequencing is performed on a proportion of positive COVID-19 test specimens. This chart also shows the total count of variant cases that have been detected in Wisconsin. DHS displays case counts for notable variants identified by the Centers for Disease Control and Prevention (CDC). See emerging variant cases in the US here.
Please note that the variant cases identified in this table likely represent a fraction of how many cases of SARS-CoV-2 variants are circulating in Wisconsin. DHS, along with the Wisconsin State Laboratory of Hygiene and other laboratory partners are working to expand efforts to sequence SARS-CoV-2 specimens and identify variants.
Data source: Wisconsin Electronic Disease Surveillance System (WEDSS) and GISAID.
The Wisconsin State Laboratory of Hygiene, along with other laboratory partners, identifies variant cases of SARS-CoV-2, the virus that causes COVID-19, through whole genome sequencing. Routine analysis of genetic sequence data allows us to identify new variant strains in Wisconsin.
We plan to update our data each Thursday by 4 p.m.
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Variants of concern identified by the CDC are listed below. Learn more about emerging SARS-CoV-2 variants on the CDC's website.
- Variant B.1.1.7 was first discovered in England in November of 2020. The variant was first reported in the United States in December 2020 and was first identified in Wisconsin in January 2021.
- Researchers believe this new strain spreads more rapidly and easily than the original strain of SARS-CoV-2. B.1.1.7 may also be associated with an increased risk of death but more studies are needed to confirm this.
- Variant B.1.351 was first discovered in South Africa in samples dating back to October 2020.
- Researchers have found that this strain also spreads more rapidly and easily than the original SARS-CoV-2 virus. It is not yet known if this variant has any impact on disease severity. There is some evidence that this variant may affect how vaccine induced antibodies respond to this virus.
- Variant P.1 was first discovered in four travelers from Brazil who were tested at an airport near Tokyo, Japan in early January 2021.
- Researchers have found this strain also spreads more rapidly and easily than the original SARS-CoV-2 virus. The P.1 variant also has unique genetic mutations that may affect the body's ability to recognize and fight off the virus. Typically antibodies developed through previous COVID-19 infection or through vaccination can fight off the SARS-CoV-2 virus. However, if the virus has mutated, antibodies may not recognize it and leave you exposed to COVID-19 infection by this strain.
Variants are identified through a process called whole genome sequencing. Whole genome sequencing takes a sample of the virus from a positive SARS-CoV-2 test specimen and reads its genetic code. Genomic sequencing allows scientists to identify how virus samples from different people might have different genetic characteristics. This way, they can look out for new variants of the virus and understanding changes in the characteristics of the virus, like how easily it spreads from person-to-person.
DHS, the Wisconsin State Laboratory of Hygiene, and other laboratory partners regularly perform whole genome sequencing on a portion of positive tests. DHS has also requested that clinicians identify cases that may be good candidates for genome sequencing, such as individuals who have traveled internationally or individuals who may have tested positive after being fully vaccinated.
Sequencing of SARS-CoV-2 is not a diagnostic (Clinical Laboratory Improvement Amendments (CLIA) validated) test. It is performed strictly for public health surveillance purposes and is not meant to advise patient care. Results will not be reported to the submitter or patient.
By sequencing SARS-CoV-2 genomes in Wisconsin, we improve our understanding of emerging variants and use this information to inform public health decision-making.
With emerging strains of SARS-CoV-2 circulating in Wisconsin, including those that may spread more rapidly and easily, it is essential to continue public health practices and prevent the spread of COVID-19. Wear a mask, practice physical distancing, stay home whenever you can, wash your hands frequently, get tested if you have symptoms or are a close contact, and get vaccinated when you are eligible.
We are still learning about these variants and how they affect:
- Transmissibility: How easily the virus spreads from one person to another.
- Gene mutation D614G was found in all three notable variants. This mutation allows these variants to spread more quickly than the original SARS-CoV-2 virus.
- Disease outcome: How ill people get with COVID-19.
- Emerging evidence suggests that B.1.1.7 may be associated with an increased risk of death compared to the other variants. More studies are needed to confirm this.
- More studies are needed to determine if P.1 and B.1.351 are associated with more severe illness.
- Response to COVID-19 treatments: How well therapies and medicines work.
- Therapies and medicines for people with COVID-19 use specific antibodies to target regions of the virus and block infection. These treatments may become less effective at helping people recover as new variants emerge.
- Change in effectiveness of COVID-19 vaccines: How well vaccines work.
- The SARS-CoV-2 virus would likely need to have multiple, significant mutations to affect the level of immunity provided by vaccination.
- Based on initial evidence, all three authorized vaccines effectively reduce the risk of COVID-19 for all of the circulating variants.
All DHS COVID-19 data is available for download directly from the chart on the page. You can click on the chart and then click "Download" at the bottom of the chart (gray bar).
To download our data visit one of the following links:
You can find more instructions on how to download COVID-19 data or access archived spatial data by visiting our FAQ page. The data dictionary (PDF) provides more information about the different elements available in the data above.