Illinois cases of a COVID-19 variant first discovered in the United Kingdom that is believed to be more transmissible rose 53% in the past seven days, according to data released Thursday by the Illinois Department of Public Health.
In all, 3,168 cases involving the variant, known as B.1.1.7, have been found in samples of COVID-19 positive tests from Illinois since Jan. 15, officials said.
The COVID-19 virus — also known as SARS-CoV-2 — constantly changes through mutation, and new variants of a virus are expected to occur over time, officials said.
The variants helped fuel a spring surge of COVID-19 cases in Illinois, with the Peoria region as well as Chicago and suburban Cook County hit particularly hard, according to data from IDPH.
That surge appears to be easing, even as cases involving the variant continue to rise, according to the data.
A total of four COVID-19 variants believed to be more transmissible have been discovered in Illinois.
Cases of the P.1 variant, which was first discovered in Brazil, jumped 62% in the past seven days to a total of 1,097 cases, officials said. The variant was first discovered in Illinois March 5, according to state data.
Cases of a variant known as B.1.427/B.1.429, which was first identified in July 2020 in Los Angeles County, rose 22% to 428 cases, according to state data. The variant was first identified in Illinois March 25.
Fifty-six cases of the variant first discovered in South Africa, known as B.1.351, have been identified in Illinois since Feb. 11, according to state data.
More study is needed about the infectiousness and severity of the California and Brazilian variants, according to IDPH officials.
To prevent the spread of COVID-19 and its variants, Illinois officials are urging people to wear a mask, stay 6 feet away from those who are not in their household, avoid gatherings and unnecessary travel and wash their hands often.
Data suggests current vaccines will be effective and safe in providing protection against the South African and U.K. variants, officials said.