More than half of the recorded measles cases recorded in the region originated in Kingsville and Leamington.
The Windsor Essex County Health Unit has confirmed 69 cases of the virus since the first case was identified in February.
"In our region, the majority of cases reside in Leamington and Kingsville area which talks about the unvaccination rate but I'm concerned that this could go over to other communities," said Medical Officer of Health Dr. Mehdi Aloosh.
Dr. Aloosh said there are likely more cases in the community that have not been reported. Many of the ones that were reported have been severe.
"We've had cases who have been hospitalized so we have seen severe cases in Windsor-Essex. This is in line with the province which has seen hospitalization in some cases," said Dr. Aloosh.
The majority of cases, 32 per cent, have been found in school-aged children. To help prevent the spread of the disease, if a case of measles is confirmed in a school, any student who may have been exposed and has not received two doses of the vaccine will be excluded from school for up to 21 days.
The health unit said the best way to prevent serious illness is to get two doses of the Measles, Mumps, and Rubella (MMR) vaccine, which is 97 per cent effective.
The health unit asks residents with symptoms including cough, runny nose, fever or a rash to stay home and away from large gatherings this Easter season.
Symptoms can appear up to 21 days following an exposure and usually last for 1 to 2 weeks.
An online assessment tool can be found on the health unit's website.