Sonoma County health officials said Tuesday that at least 39 people in the region tested positive for the coronavirus despite being vaccinated, according to a statement from the county.
While Sonoma is the only Bay Area county thus far to share instances of inoculated people getting COVID-19, it’s assumed all regions are experiencing similar developments as the vaccines do not provide complete protection.
“This result is not unexpected,” county spokesperson Matt Brown told SFGATE. “We know that the various vaccines are not 100% effective.”
These 39 instances represent 1% of the total positive cases over the last four months, according to the county.
“We expect this rate to be present in other counties as well,” Brown said.
Contact tracing revealed that none of the infected individuals transmitted the virus to others, according to the Press Democrat, which broke the story about the cases. Also, only one of the 39 people was hospitalized with moderate illness for a short period.
“We’ve been monitoring the contacts of these people that have tested positive (after vaccinations) and there doesn’t seem to be any transmission from these folks, these breakthrough cases, to subsequent contacts,” Jenny Mercado, a county epidemiologist, told the Press Democrat. “That’s really the most important message, besides not having any severe outcomes.”
None of the three vaccines authorized for emergency use in the United States — Pfizer, Moderna or Johnson & Johnson — offer complete protection from the coronavirus, and public health officials say some people who have completed a vaccine series will still contract the virus. When this happens, it’s called a “breakthrough case.”
“We absolutely expect this to happen with these outstanding mRNA vaccines,” said Dr. John Swartzberg, referring to the fact that the two most common vaccines, Moderna and Pfizer, provided 90% to 95% protection respectively in vaccine trials. “We know that it’s not going to happen in 90% to 95% of people who get vaccinated, which means it’s going to happen in 10% to 5%. It’s anticipated we will see this.”
While fully vaccinated people can still get COVID-19, research shows that they tend to develop mild symptoms or are asymptomatic.
Swartzberg said this information is a good reminder for people to continue practicing social distancing and mask wearing. He also said it shows we need to drive down COVID-19 cases in our communities, bringing the virus under better control, so both those who are vaccinated and unvaccinated have a low chance of contracting the virus. “We have to get community control,” he said.