South Africa’s COVID-19 variant found again in Santa Clara County

The worrying South African strain of the COVID-19 virus, which appears to be more contagious and more resistant to some vaccines, has surfaced in Santa Clara County.

Unlike the first case, detected in February, this new case is not related to travel and is believed to have resulted from transmission in the community. Health officials did not provide further details.

“This last case confirms that we have transmission in the community and reminds us not to let our guard down in the middle of this pandemic,” said Dr. Sara Cody, health officer and public health director for Santa Clara County, in a statement.

“Considering national trends, we have been operating on the assumption that these variants were circulating at some level in our communities,” she said.

It is the fourth reported case in California. In February, authorities announced the detection of a case in Santa Clara County in an adult who traveled internationally but was quarantined after experiencing symptoms. Another February case was reported in Alameda County. The authorities have not informed the source of the fourth case.

The South African variant is capable of evading the AstraZenca vaccine, although two other vaccines – manufactured by Moderna and Johnson & Johnson – offer some protection.

But, despite the danger, this South African variant has not gained much space in the United States. First detected in the United States in January in South Carolina, only 142 cases in 25 states were found.

In contrast, two other strains – one that emerged in California and the other imported from the UK – are causing widespread concern.

It is estimated that one, now called the West Coast strain, is 20% more transmissible than the original variant in circulation. Another, imported from the United Kingdom, is considered to be up to 50% more transmissible. The South African variant is also considered to be about 50% more contagious.

There were 6,628 cases of the West Coast strain in California. In mid-February, it accounted for more than half of all samples sequenced in California, more than a third of samples from Nevada and a quarter of samples from Arizona.

This week, the CDC declared the strain grown at home to be a “variant of concern,” citing its ease of contagion and its ability to dull the body’s immune response.

There were 375 cases of the variant in California in the United Kingdom. But it is appearing elsewhere. It has been found in all 50 states and the District of Columbia and is on track to become the country’s dominant variant.

In the county of Santa Clara, 15 cases have been associated with this variant in the United Kingdom.

Last Saturday, California reported its first case of a dangerous variant from Brazil. It is not known how the patient, a man from San Bernardino County, acquired the infection. This strain is exclusive to another Brazilian variant, which was found in the Bay Area, but is considered less dangerous.