Ventura County administered thousands of vaccines that may not have worked

Ventura County officials are scrambling to contact thousands of patients who received vaccines that may have been ineffective because county workers stored them at the wrong temperature.

Approximately 23,000 patients who got shots at county clinics between October 2017 and November 2018 need to be revaccinated, county officials said. But so far, fewer than 5% of those affected have returned to get their shots, raising questions about how protected residents will be from this year’s flu season as well as other disease outbreaks.

In October 2017, Ventura County officials changed a packaging process to ensure that vaccines traveling from agency headquarters in Ventura to clinics as far away as Simi Valley would not become dangerously warm.

Most vaccines need to be stored at 35 to 46 degrees Fahrenheit, according to the U.S. Centers for Disease Control and Prevention.

“Exposure to temperatures outside these ranges may result in reduced vaccine potency and increased risk of vaccine-preventable diseases,” according to the CDC.

But when workers began cooling vaccines with ice, some of the shots dipped to temperatures below the safe range, “possibly compromising the effectiveness of most of these vaccines and medications,” according to a statement from the county.

Last month, the county began calling and sending letters to those who may have been affected, stating they were contacting them “out of an abundance of caution.” They also extended hours at several clinics to make it easier for people to drop in. Twenty-five types of vaccines may have been affected, including the flu shot and the HPV vaccine, officials say.

So far, however, only 1,200 people have gotten repeat vaccinations, according to health officials. Some may be concerned about the risks of being vaccinated twice.

Health officials, however, say the real risk is remaining unprotected against diseases. Opting for another vaccine is similar to getting a booster shot, they say.

“Routine vaccines can require five or more doses in childhood,” the Ventura County Health Care Agency states. “Repeating one of these doses is just as safe as receiving the next routine dose in the series.”

Some injectable medicines were also possibly neutralized by too-cold temperatures, including 527 doses of penicillin, which is used to treat syphilis. Patients likely do not need a repeat dosage if their syphilis infection has already resolved, according to health officials.

The county is not charging people to get revaccinated or retreated. If everyone contacted gets their shots again, the price tag for the county will be as much as $1.35 million, according to the Ventura County Star.

To prevent similar problems going forward, the county is now tracking vaccine-package temperatures with thermometers. They are also looking into shipping vaccines directly from wholesalers to clinics, so they do not need to be routed through the county agency, cutting down on travel time.

“The Ventura County Health Care Agency has resolved the root cause of this issue and, as always, makes the health and well-being of our patients our first priority,” the agency said in a statement.

soumya.karlamangla@latimes.com

Twitter: @skarlamangla