With measles cases on the rise both globally and in Ontario, local health experts are urging families to stay informed and take action to prevent further spread — especially in communities with lower vaccination rates. Dr. Jeya Nadarajah, a lead infection control physician at Oak Valley Health, shares key facts and tips every household should know.

Measles is back — and it’s serious

According to the latest report from Public Health Ontario, recent measles cases are mostly linked to international travel and exposures in unvaccinated individuals. However, the sharp rise in global cases — and the potential for local outbreaks — raises concern, especially in under-vaccinated communities.

Know the symptoms

Early signs of measles can be mistaken for a cold or flu: fever, cough, runny nose, and red/watery eyes. A few days later, a red rash typically begins on the face and spreads downward. Tiny white spots inside the mouth may also appear. Complications can include pneumonia, brain swelling (encephalitis), and severe dehydration—especially dangerous for young children.

Protection: the MMR vaccine is highly effective

The MMR (measles, mumps, rubella) vaccine is your best line of defense. One dose provides about 93 per cent protection, and two doses — routinely given in Ontario — offer 97 per cent effectiveness. If you’re unsure about your or your child’s vaccine status, talk to your health care provider.

The MMR vaccine has a long-standing record of safety. Claims linking the vaccine to autism have been thoroughly discredited, and the original study was deemed fraudulent. The real risk lies in the disease: 1 in 20 children with measles will get pneumonia, and 1 in 1,000 may suffer brain inflammation.

Babies under one year old can’t yet receive the MMR vaccine. Protect them by ensuring that everyone around them — family members, caregivers, playmates — is vaccinated. Avoid unnecessary travel to outbreak zones and limit contact with anyone who’s sick.

What to do if you think you’ve been exposed

Stay home and call your health care provider or local public health unit immediately. Monitor for symptoms for up to 21 days. If you need to visit a clinic or hospital, call ahead to avoid exposing others. Public Health Ontario also shares up-to-date exposure alerts and guidance here.

Measles spreads alarmingly fast

Measles is one of the most contagious viruses, spread from coughing and sneezing as well as direct contact. It can linger in the air for up to two hours, and one infected person can spread it to 12-18 unvaccinated people. Up to 90 per cent of non-immune individuals exposed will contract the virus.

No cure — only prevention

There is no specific antiviral treatment for measles. Care focuses on rest, fluids, and fever management. In some cases, children may receive vitamin A to reduce complications. Prevention through vaccination remains the most effective tool.

Schools and hospitals are on alert

In health care settings, suspected measles patients are quickly isolated, and staff wear special protective gear. Health care settings also have specialized isolation rooms for individuals suspected of having measles. Schools are working closely with public health to confirm student vaccination records. In the event of an outbreak, unvaccinated students may be asked to stay home.

Measles is entirely preventable — and so are its potentially devastating complications. Stay informed, check your immunization records, and reach out to public health if you need support. Local public health units offer free, culturally sensitive support and vaccine catch-up programs.

Dr. Nadarajah encourages: “We all have a shared responsibility to protect our most vulnerable, like infants and immunocompromised individuals.”

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This article appeared in the May 2025 issue of The Link. To receive Oak Valley Health’s community newsletter, subscribe now.