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Measles infections are increasing and increasing in multiple provinces, with more cases already this year than all 2024.
Local public health alerts on the new cases come with detailed descriptions of the person’s whereabouts before being diagnosed.
They tell us what hours and minutes a passenger spent in airports in Vancouver, Toronto and Fredericton, how long other patients were in a Emergency Department north of Toronto or Family Health Clinic In eastern Ontario, and how long someone visited a sitting chain restaurant in the Laurentians of Quebec.
The ads raise a couple of questions: Why do measles cases seem to be sliding through the fingers of health professionals, or are not even recognized by patients or their families?
And why give such a detailed information about where a person was?
The answers lie in the incredibly contagious that is the measles virus, along with the vaccination by the cornerstone of the cornerstone in the propagation.
“What these ads are trying to do is make people aware that they can protect … others around them and be careful with their own symptoms,” said Caroline Colejn, an epidemiologist who has a research chair in Canada 150 at Simon Fraser University in Burnaby, BC
Last month, Colejn and his co -authors published a Modeling study In measles to see what happens when respiratory disease is introduced into a community, and what level of vaccination or prior immunity of infection is needed to prevent outbreaks.
“Because measles is incredibly infectious, it can spread rapidly, even if most people in a community, 80 percent, for example, are immunized,” said Colejn. “The usual threshold is that he wants 95 percent of people in a community to have been vaccinated or had prior measles exposure.”
However, vaccination rates have been falling in Canada and other places, and the first symptoms of measles can be not recognized, which increases the risk of propagation.
Resistant and highly contagious viruses
Measles extends through the air when someone coughs, sneezes or speaks, so even spend a few minutes in that same airspace can represent a risk of infection for someone who is not vaccinated, like a baby who is too young to receive the shots. A single infected person can infect 90 percent of their nearby contacts, if they are not vaccinated.
The virus that causes measles is also resistant, persistent on surfaces for two hours After an infected individual.
That is why case counts can spiral quickly. A single person, on average, infects 12 to 18 others which are susceptible to measles.
That means that if a patient infects another 15, that each infects another 15, ends with 225 cases. If each of those people infects another 15, you are at 3,375 cases, etc.
Another wrinkle is that measles symptoms overlap with more common respiratory diseases, including influenza, which is also circulating In Canada now.
When someone who is vulnerable to measles virus is exposed, they can show Reference points “3 C” of the infection about 10 days later:
- Coryza, or inflammation of nasal mucous membranes, which leads to a nose that
- Conjunctivitis or redness of the eyes.
“These are very similar to the things we would see with the flu,” said Dr. Mark Kirchhof, elected president of the Canadian Dermatology Association and associated professor at the University of Ottawa. “It can be easily confused.”
When people without knowing it infected with measles attribute the symptoms to influenza, a cold or COVID-19, especially at the beginning, they can interact with the family, go to school, work and other public places and expose others that have not been vaccinated, Kirchhof said.
That is why local public health officials and doctors encourage people to call in advance before coming to a clinic if the person is not vaccinated and shows cold symptoms. In this way, staff can cordon off an area to avoid greater measles spread.
The measles eruption appears on the face first
When the Canadian dermatology association observed an increase in measles in 2023, the group began to raise awareness about measles eruption, other symptoms and who is vulnerable to complications.
Kirchhof said dermatologists can lend a hand to help colleagues recognize measles, of which many doctors have only read in textbooks and have never seen in real life.
Two or three days after the symptoms of cough, a nasal secretion and a conjunctivitis in someone infected with measles, a group of white points will often appear inside the cheeks near the molars. These are known as Koplik points after the pediatrician who first identified the pattern’s link to measles infection.
Measles declared himself eradicated in Canada in 1998, but with the fall of vaccination rates, new cases are increasing; 95 people have been infected in the first two months of this year, compared to 147 for all 2024.
Then, a few days after Koplik spots appear, a characteristic eruption begins in the face and extends to the neck, legs, arms and feet.
“The eruption itself is red points,” Kirchhof said. “Some of them may feel, and some may be planes. Sometimes they can be grouped to form larger red areas on the body, and in some patients it can have itching.”
Depending on the skin tone, the brightness of the eruption can vary, doctors say.
It is the delay between exposure and when the measles symptoms explode, followed by the time of delay between the types of symptoms that explain why someone who finally seeks treatment can go through airports, schools, groceries and hospitals before being diagnosed.
Initially, measles affects respiratory tract, and common complications include ear infections.
But measles can also lead to high hospitalization rates. It is estimated that almost one to three out of every 1,000 children who infect will die from complications, such as pneumonia and a swelling of the brain called encephalitis.
There is no specific treatment for measles infection, which needs to continue its course.
Counteract the fall in child immunization rates
The best prevention, public health officials in Canada and international stress, is vaccination.
But, in the midst of decreased vaccination rates, some people on the Internet or social networks can promote treatment That lack of evidence, Kirchhof said, such as vitamins or supplements that maintain general health, although they do not specifically treat measles.
On the contrary, federal figures reflect the power of high vaccination rates to stop outbreaks. Before Measles, paper and rubella (MMR) Vaccines began to be implemented in Canada in the 1970s, tens of thousands Cases occurred every year.
More recently, Fall vaccination rates In children in Canada and International trips reintroduce the virus too contributed For outbreaks, scientists say.
Dr. Sarah Khan, a specialist in infectious diseases and associated professor at McMaster University, was part of the team that took care of a non -vaccinated child who died of measles last year in Hamilton.
“It is devastating when you have to control a preventable vaccine disease that results in a fatality,” Khan said.
Given the moment and other factors, Khan said that driving even a single case of measles can be a challenge.
Doctors say that those with a higher risk of exposure, such as a baby or someone who is pregnant, can benefit from a medication called immunoglobulin To reduce the risk of developing measles.
“It really requires early recognition, early notification and a lot of coordination for all exposed people,” Khan said.
