LOS ANGELES—Health officials in Los Angeles County said over 25% of new coronavirus cases are among those who have been fully vaccinated, an increase from last month, according to a report Wednesday.

Health officials have called the vaccines effective and said breakthrough cases are to be expected, but the number is a noticeable increase from June when fully vaccinated individuals accounted for 20% of the county’s infections, Fox 11 Los Angeles reported.

"As more people are vaccinated, the number of fully vaccinated people becoming infected will increase and with the Delta variant that’s far more infectious, exposures to infections have also increased," Barbara Ferrer, the public health director from the county, said, according to the station. .

Tomás Aragón, director of the California Department of Public Health and state public health officer, said in a statement obtained by the Los Angeles Times that masks should be worn while inside public places regardless of the individual’s vaccine status

The state’s health officials told the paper that the individuals who are not vaccinated are the ones "driving up cases and hospitalizations in the state."