understanding measles: what parents need to know about risks, complications and vaccination

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measles is just a little rash and fever that clear up in a few days. while true, measles can be mild in adults, the stakes are much higher in children, especially kids under five.

by karen hawthorne

published may 20, 2025

4 minute read

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4 minute read

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this is why outbreaks of measles have people so concerned: it is one of the most contagious viruses in the world and it can be fatal. the sobering fact, according to the u.s. centers for disease control and prevention, is nine out of 10 people exposed to measles will catch it if they are not protected by vaccination, have not had the disease before or have a weaker immune system.

even brief exposure poses a high risk for people who are not immunized.

canada eradicated measles in 1998 but it’s back

the measles vaccine was introduced in 1963, curbing global epidemics that would happen every few years, taking the lives of 2.6 million people every year. canada eradicated measles in 1998 but it’s back. the resurgence has been attributed to declining vaccination rates, international travel reintroducing the virus into canada, and the highly contagious nature of the disease itself.

the vaccine, called mmr, protects against measles, mumps and rubella, and is given to children as a series of two doses: the first dose is given at 12 months, and the second dose is given between ages four to seven. a 2024 report in the canadian journal of public health revealed that vaccination rates have dropped to 82.5 per cent, a significant decline observed before, during and after the covid-19 pandemic. experts say the vaccine is the most important protection parents and caregivers can provide for their kids. measles is a preventable disease.

children at much higher risk for serious complications of measles

there is a misperception that measles is just a little rash and fever that clear up in a few days. while true, measles can be mild in adults, the stakes are much higher in children, especially kids under five. common complications are ear infections and diarrhea, and there are also serious health consequences like pneumonia, hearing loss, swelling or infection of the brain, and death.

more than a quarter of infected children under age five will need to be hospitalized.

measles is an airborne disease that spreads easily through respiratory droplets, so when an infected person breathes, coughs or sneezes, virus particles are released into the air. another important fact is that these particles can remain infectious for up to two hours, even after the person has left the area. this extended period of contagiousness makes it especially challenging to control. as well, an infected spread can spread the virus from four days before the telltale rash appears until four days after its onset. people can transmit the disease before they even know they’re infected.

measles symptoms and what steps to take

measles symptoms happen seven to 14 days after contact with the virus. symptoms to watch for include the following:

high fever
cough
runny nose
red, watery eyes
rash

how to describe the rash? it starts as flat red spots on the face that then move downward to cover the whole body. smaller raised white spots may appear on top of the red rash, joining together as the rash travels down the body into blotches of coloured reddish bumps. on darker skin tones, the rash may look brown, purple or grey. after about five days, the rash diminishes in the same order it appeared.

if you suspect your child has measles, toronto’s sickkids hospital advises the following steps:

provide the child with a mask (if able to tolerate use and there are no contraindications) when providing care.
isolate the child in a single room with the door closed to prevent transmission to others. the child should isolate at home, and can’t go to school or daycare until at least five days after the rash first appears.
contact the child’s healthcare provider for further assessment, testing and care.
contact your local public health unit immediately to report the suspected case and to receive additional guidance. do not wait for laboratory confirmation.

measles is identified through a physical examination of the child and confirmed by a healthcare provider who may order blood and urine tests as well as viral swabs from the nose or throat.

the decline in vaccine uptake poses a significant public health challenge

note that children and families most at risk are those who are not vaccinated against measles, have recently travelled to an endemic region or are immunocompromised. in addition to routine immunization, health officials are recommending that people born after 1970 who are unimmunized or have only received one dose of a measles-containing vaccine book an appointment to be immunized, unless they are pregnant or immunocompromised (they should talk to their care provider). also, people born before 1970 may consider getting one dose of vaccine if the risk of exposure is high, if you’re travelling to an endemic area.

the decline in vaccine uptake poses a significant public health challenge, potentially leading to the re-emergence of other vaccine-preventable diseases like pertussis, diphtheria and polio. and reduced herd immunity puts vulnerable populations at increased risk for disease.

karen hawthorne

karen hawthorne worked for six years as a digital editor for the national post, contributing articles on health, business, culture and travel for affiliated newspapers across canada. she now writes from her home office in toronto and takes breaks to bounce with her son on the backyard trampoline and walk bingo, her bull terrier.