Vaccinated individuals should continue to wear masks in public: researchers

Vaccinated individuals should continue to wear masks in public because they can still carry – and possibly shed – as much virus as unvaccinated people and not realize it, data from a new study confirms.

Researchers studied viral levels at diagnosis in 869 patients, including 632 who were asymptomatic. Most of the infections were caused by the highly contagious Delta variant of the coronavirus.

They found no statistically significant differences in average viral loads between vaccinated and unvaccinated individuals, or between those with or without symptoms, or among different age groups, genders, or vaccine types, according to a report posted on medRxiv on Tuesday ahead of peer review.

“Our study does not provide information on infectiousness,” said Richard Michelmore of the University of California, Davis, noting that virus transmission is influenced by several factors, not just vaccination status and viral load.

“It is not OK to assume that because you are vaccinated that you cannot become infected and cannot infect someone else, even if asymptomatic,” he said.

COVID-19 vaccines do decrease the odds of infection and reduce infection severity. However, people vaccinated against COVID-19 should still wear masks in public because they might infect others if they themselves become infected, researchers advised.