LANSING — People who visited a south Lansing gas station during a two-hour period overnight from April 11 to 12 may have been exposed to measles, according to the Michigan Department of Health and Human Services.

The Speedway at 6041 S. Pennsylvania Ave. is listed as an exposure site in the department's latest release about the ongoing measles outbreak in Michigan. People who visited the gas station between 11 p.m. April 11 and 1 a.m. April 12 may have been exposed to the disease.

The measles virus stays active in the air for about two hours after an infected person sneezes, coughs or breathes, department spokeswoman Lynn Sutfin said. Symptoms can appear within 21 days of exposure.

More than Lansing:Where you may have been exposed throughout Michigan

More:Measles in Michigan: What you need to know about vaccines and prevention

Ingham County Health Department officials are looking for people who were exposed so they can learn whether they are vaccinated, Health Officer Linda Vail said.

People who were exposed but have been vaccinated or previously contracted measles are safe, she said. People who are unsure about their vaccination history can call their doctors or the health department to review records. People who were exposed and are not vaccinated should contact the department.

Although draining for local public health workers, the exposure was limited in Ingham County, Vail said. It was one person who went inside one gas station late on a Thursday night. It could have been a lot worse.

"Just think about if it was, 'oh this person went to the mall,'" she said. "Then it gets really, really hard and it gets really, really big."

When someone contracts measles, public health workers start an investigation to find out what places that person visited while infectious. That's how they come up with the list of exposure sites, Vail said. It can take days.

Then, public health workers track down people who may have visited those exposure sites. That also takes a lot of work, and it might just lead to more.

"It's doing that detective work," she said. "That one [case of measles] potentially leads you to another. That person was unvaccinated, was exposed, and in the several days before that person could come down with symptoms, [we have to keep] track of where they’ve been."

About Michigan's measles outbreak

Since the outbreak started in mid-March, 42 Michigan residents have been diagnosed with measles, a disease that can be prevented with a vaccine. The infected individuals range from 8 months to 63 years old, according to the health department, and live in Oakland and Wayne counties.

The most recent cases involve two adults, one from Oakland County and one from Detroit. One of those people traveled to Ingham and Kent counties while infectious.

Newly identified measles exposure sites include:

April 10, Beis Chabad of North Oak Park, 15401 West 10 Mile Road, Oak Park, 7:45 –10 p.m.

April 11, Beis Chabad of North Oak Park, 15401 West 10 Mile Road, Oak Park 7:45 –10 p.m.

April 11, Speedway Gas Station, 6041 S. Pennsylvania Ave., Lansing, 11 p.m. – 1 a.m.

April 12, Baymont by Wyndham Grand Rapids Airport, 2873 Kraft Ave. SE, Grand Rapids, approximately 12 – 3 a.m.

April 12, BP Gas Station, 1166 Encorse Road, Ypsilanti 11 a.m. – 2 p.m.

April 12, Urgent Care Med Express 3100 Plainfield Ave NE, Grand Rapids, 1 – 6 p.m.

April 12, Congregation B’Nai Israel, 15400 West 10 Mile, Oak Park, 5 – 7:30 p.m.

April 13, Beis Chabad of North Oak Park, 15401 W 10 Mile Rd, Oak Park 9:30 a.m. – 2 p.m

Other exposure sites are listed on the state's informational website about the 2019 measles outbreak.

More about the measles vaccine

The measles vaccine is safe and effective. It can prevent the disease from taking hold if administered within 72 hours of exposure, the Michigan Department of Health and Human Services states.

Here's where to find it locally:

Clinton County: Mid-Michigan Health Department, 989-224-2195, visit mmdhd.org.

Mid-Michigan Health Department, 989-224-2195, visit mmdhd.org. Ingham County: Ingham County Health Department, 517-887-4316, immunize@ingham.org.

Ingham County Health Department, 517-887-4316, immunize@ingham.org. Eaton County: Barry-Eaton County Health Department, 517-541-2643.

Measles symptoms

Measles is highly contagious. The virus lives in the air for two hours after emitted by an infectious person. Symptoms typically occur within 7 to 14 days of exposure.

Symptoms include:

High fever

Cough

Runny nose

Red, watery eyes

Tiny white spots on the inner cheeks, gums, and roof of the mouth (Koplik Spots) 2-3 days after symptoms begin

A rash that is red, raised, blotchy; usually starts on face, spreads to trunk, arms, and legs 3-5 days after symptoms begin

More:How to talk to other parents about whether their kids are vaccinated

This story will be updated.

Contact Carol Thompson at (517) 377-1018 or ckthompson@lsj.com. Follow her on Twitter @thompsoncarolk.