The number of positive cases of COVID-19 in the Baltimore County Public Schools doubled earlier this month.

Baltimore County Health Officer Dr. Gregory Branch said too many people are letting down their guard.

“You’ve got people feeling a little bit more lax when it comes to their mask wearing and their hand washing, stuff like that, all of that is going to increase the number of outbreaks that you have,” Branch said.

In addition, he said, people are inside more because of the cold weather and the new omicron variant has emerged.

According to data released by the school system, there were 420 positive cases of COVID among students and staff in the county schools during the week that ended December 3. That compares to 214 cases the week before Thanksgiving. Also, more than 1,300 people were quarantined.

Branch also said not enough children are vaccinated.

“So, the transmission in the community is still very high to substantial so that transmission is in the schools too.”

County school officials declined to comment Monday on the COVID cases. School officials have said in the past that most of their cases of COVID-19 are transmitted in the community, not in school buildings.

Branch added a good reason to get vaccinated now is to have it on board before Christmas travel begins.

“If you get a booster, which is your third shot, within 48 hours you will be completely boostered,” Dr. Branch said.

The second shot takes up to 14 days to take full effect.

“This is a critical time, that if you’re going to be traveling on or near Christmas to get your second dose.”