Should we be concerned about climbing global measles cases?

“PHAC is closely monitoring the situation in the United Kingdom,” said Anna Maddison, spokesperson for Health Canada and the Public Health Agency of Canada.

The World Health Organization’s (WHO) European region has reported “an alarming rise” in measles cases. Over 30,000 measles cases were reported by 40 of the region’s 53 member states between January and October 2023 — compared to 941 cases reported in all of 2022, according to information published in December 2023. This increase represents a more than 30-fold rise.

Although measles was deemed eliminated in Canada in 1998, cases and outbreaks can occur when an individual travels to a country where measles is circulating and brings the disease back to Canada — particularly if the individual is unvaccinated or not fully vaccinated, the PHAC says.

Currently, there is a Level 1 travel health notice advising Canadians to “practice health precautions” when travelling.

Public Health Ontario said it is continuing to monitor measles epidemiology closely.

Between January and November of 2023, six cases of measles occurred in Ontario, the majority of which were considered to be travel-related.

“This is lower than the average number of cases in the five years prior to the pandemic,” PHO reports.

“The increased level of measles activity currently in the U.S., U.K., Europe and elsewhere is an important reminder of the risk of measles and the importance of vaccination in preventing infection,” said PHO.

“Ontarians, who are planning to travel for March break or the summer, are encouraged to review their family’s immunizations now to ensure they are fully protected against measles before their travel.”

Children in Ontario are recommended to receive two doses of measles vaccine before the age of 7, the first dose at 12 months of age and the second dose prior to school entry.

However, PHO reports the COVID-19 pandemic caused significant disruptions to the delivery of routine immunizations resulting in a “large decline” in measles immunization between 2020-21 and 2021-22. PHO said there have been a significant immunization “catch-up” efforts taking place since 2022.

What is the measles virus?

Measles is a highly contagious disease caused by the measles virus. Symptoms can appear seven to 21 days after being infected with the virus. People infected with measles can spread it to others before they have symptoms.

Initial symptoms include: fever, cough, runny nose, red and watery eyes, and small, white spots may appear inside the mouth and throat two-to-three days after symptoms begin. Between three and seven days after symptoms begin, a rash that looks like small red spots can develop on the face, spreading down the body, arms and legs.

The rash can last four to seven days. Most people recover from measles within two or three weeks.

How is the measles virus transmitted?

The measles virus can spread very easily, primarily through airborne transmission, from an infected person who breathes, talks, coughs or sneezes into a common airspace shared with others who are susceptible. The virus can remain in the air for several hours.

People can spread measles even before they know they have the infection or experience symptoms. Some people are at higher risk of developing severe complications from measles.

Who is most at risk?

Some people are at higher risk of developing severe complications from measles, including people who are pregnant, people with weakened immune systems and children who are less than five years of age.

You're more likely to become infected if you're unvaccinated or non-immune and travelling to countries where measles is circulating. Occasionally, a returning traveller who becomes infected abroad can spread infection in Canada. This can be especially problematic if the traveller returns to a community where many people are unvaccinated or not fully vaccinated.

How do I protect myself?

Individuals who have not had two doses of a measles vaccine or had a previous measles infection are at risk of infection if exposed to the virus. Receiving all recommended measles vaccinations is the most effective protection against infection.

The best protection against measles is vaccination with two doses of a measles-containing vaccine.

People in Canada are at very low risk of catching measles if they have received two doses of a measles-containing vaccine, if they have been infected with the measles virus in the past, or if they were born before 1970. Adults born before 1970 are generally presumed to have acquired immunity from past exposure to the measles virus.

While vaccination is considered by public health agencies to be the most effective preventive measure for measles, other measures that can be used to help reduce the spread include staying home when sick, frequently washing your hands, practising proper respiratory etiquette by covering coughs and sneezes with a tissue or bend of the arm and cleaning and disinfecting high-touch surfaces and objects.

Are you at increased risk if you travel?

Anyone who is not protected against measles is at risk of being infected when they travel internationally.

What should I do if I travel?

Travellers to any destination are advised to seek advice from a health care provider or visit a travel health clinic, preferably six weeks before travelling, to review their vaccination history, discuss any trip-related health concerns they may have and assess their health needs based on their destination and planned activities.