HARTFORD, Conn. (WTNH) — Connecticut hit a three percent COVID-19 positivity rate Tuesday. The numbers continue to climb as colder weather approaches. But where is the increase coming from?

RELATED: As COVID-19 positivity rates rise, tri-state governors take action on travel advisory

The state’s track and trace program shows it’s not coming from inside dining or schools, but the largest number is coming from informal gatherings and even things you don’t even think about like carpooling.

Contact tracing shows you’re most likely to catch the virus from someone you know. 

Mayor Luke Bronin (D- Hartford) said in a press conference this week, “The biggest driver of transmission remains those informal gatherings whether it’s family gatherings or whether it’s groups of friends.”

RELATED: CT health officials call out bad behaviors contributing to spread of COVID-19

And while schools may have one or two positive cases here and there, and they may have to quarantine people out of precaution, the social distancing protocols are working.

“The good news is that we haven’t seen a tremendous outbreak in any of the high schools, and I think for the most part Connecticut has done a good job,” Dr. Juan Salazar with Connecticut Children’s said.

While schools are not a problem, getting to and from school or to and from sports after school is a high-risk activity in a pandemic, especially when you’re carpooling.

RELATED: CT COVID-19 infection rate increases to 3%, hospitalizations increased by 22, five COVID-related deaths

Doctors at Connecticut Children’s said people need to think of their car as a closet or a very small room. The more people in it, the higher the risk. Even when wearing masks, it can still be problematic because there is so little airflow inside the car. 

For those who think rolling down the window will help, doctors said it really doesn’t increase the air circulation enough, especially when there are many people in as tight of a space.

“The reality is, you’re in such close space that unless you have a convertible that is getting all the air out it’s going to be very difficult,” Dr. Salazar explained. “They’re shedding virus through their nose and mouth and they are speaking and talking, and a small car that individual is certainly going to transmit the virus to the members in that car.”

RELATED: Officials change recommendations for travelers flying into CT as state COVID-19 rates increase

But there are a couple of things you can do to lower the risk: Have a consistent carpool with the same people every time, wear the mask and do a quick screen before people get inside the car.

“No fever, no cough, no runny nose, no symptoms consistent with COVID-19 before you get in the car than it is less likely [you] will spread the virus,” Dr. Salazar said.

He said the next three months are going to be the hardest, especially with the holidays Halloween, Thanksgiving, Hanukkah and Christmas coming up. Everybody wants to get together and everybody is indoors.