Less than 1% of fully vaccinated catch COVID
Just 142 people, or 0.02 percent of Houston residents who are more than 14 days past their second COVID-19 shot, caught the coronavirus after being fully vaccinated, according to the Houston Health Department.
None of those people have been hospitalized, said Dr. David Persse, the city’s health authority. The data goes back to January, when the first wave of vaccine recipients were inoculated with their second shots.
The COVID-19 vaccines are meant to reduce severe infection and death rates, not entirely eliminate the disease. They do not eradicate the risk of getting the virus. All three vaccines currently authorized for emergency use — Pfizer, Moderna and Johnson & Johnson — found high rates of effectiveness in preventing hospitalizations.
“This vaccine is not dissimilar from other vaccines in that it gives you some level of protection, but no vaccine is 100 percent effective,” Persse said. “People have to continue to consider the situations they find themselves in.”
It’s a sign the vaccine is working to prevent further infections and hospitalizations, experts said, as COVID-19 case rates slowly rise across the country. Harris County has reported more than 382,000 cases since the pandemic began in March 2020.
“While tens of hundreds of thousands have been vaccinated, in a community that still has viral spread, it’s not too big of a surprise there are a small number of people who have become infected,” Persse said.
Harris County Public Health officials said 96 out of more than 106,000, or .09 percent, of residents who were fully vaccinated through a county public health site have tested positive for COVID-19.
COVID-19 cases in patients who have already been fully vaccinated are usually mild, according to the Centers for Disease Control and Prevention. A federal study of health care workers released in early April found that the twodose vaccine regimen was
90 percent effective in preventing symptomatic COVID-19 cases.
More than 25 percent of Texans over the age of 16 have been fully vaccinated, according to a Houston Chronicle data analysis.
“The data from Houston is showing a very low percentage
of people actually go on to get clinical COVID after having the vaccine,” said Alan Barrett, director of the Sealy Institute for Vaccine Sciences at the University of Texas Medical Branch in Galveston.
The vaccine efficacy rate also depends on whether a
person adheres to public health guidelines, medical experts said. A fully vaccinated person who continues to wear a mask and avoid crowds will be less atrisk of catching the virus than a fully vaccinated person who does not practice social distancing guidelines. Barrett said there is one caveat to keep in mind when looking at Houston’s data: Some fully vaccinated people may have asymptomatic infections. They’re unlikely to test themselves for the virus.
While the number of positive COVID-19 cases in Houston’s vaccinates population is expected to go up, city health officials don’t expect a large jump.
“Only when the amount of illness in the community goes down will this go down,” Persse said.
Some variables may affect the vaccines’ efficacy — manufacturers still don’t know how long antibody protection lasts, and while the shots are effective against the COVID-19 variants in circulation, that could change if another variant develops.
It’s possible people will need to return for COVID-19 vaccine booster shots in the future, Barrett said. But for now, it’s a good start.
“I think it’s a great success story,” Barrett said.