Ask the Pharmacist – measles

Q. I am hearing much about measles recently. What exactly is measles and should I be concerned?

A. Just as we have passed the peak of Covid-19, influenza and RSV infections, we are now hearing about yet another highly contagious disease that is catching the attention of infectious disease specialists.

Measles has been around for centuries with the first documents of measles written by a Persian doctor dating back to the 9th century. In the early 1900’s, the United States required health authorities to report all cases of measles to gain a better understanding control its spread.

It became clear that measles is caused by the highly contagious morbillivirus and is known to be spread by airborne transmission and through contact with respiratory secretions from our nose and mouth. Therefore coughing, sneezing, and speaking all increase its transmission. Also, the droplets that are released into the air can remain for an hour after the infected person has left the room. This means that you can be exposed to measles by sharing drinks or meals with an infected person, kissing and/or hugging someone who has the measles, shaking hands or holding hands with an infected person, touching a contaminated surface and then touching your mouth, nose or eyes. After exposure to the measles disease, it can take 7 to 21 days for symptoms to appear.

Back before the measles vaccine was available, if measles was known to be in a room, it was likely that 12 to 18 people would become infected with it. Compare that with Covid-19 where only 1- 2 people would become infected in this manner according to the CDC.

Measles is a very preventable disease since the vaccine came to market. The measles vaccine was first developed in 1963, improved in 1968 and since 1971 the measles, mumps and rubella vaccines were combined into one called the MMR vaccine. Traditionally, the vaccine is given as a two-dose series with the first given around age 1 and a second dose between the ages of 4 and 6. The measles virus was effectively eliminated in Canada in 1998 and in the United States in 2000.

For countries to sustain the elimination of measles, it is important to maintain herd immunity which is achieved from protection against the disease by either a previous measles infection or the vaccine. This herd immunity helps protect those individuals that are unvaccinated such as those that are too young to be vaccinated, those with medical conditions that advise against vaccination and those people who are unvaccinated by choice. When the number of vaccinated people falls below a certain threshold, the community is at risk of measles losing that elimination status.

It should not come as a surprise to learn that unvaccinated people are more at risk of getting measles but, so are those individuals with a vitamin A deficiency.

For those people that do become infected with measles, many will likely encounter a mild disease. However, like many infectious diseases, there will be individuals who may not combat the disease as well as others such as the very young, the elderly, those with other medical conditions and of course, the immunocompromised.

Traditionally, when infected with measles, you will most likely experience a fever followed up with a cough, conjunctivitis, and a runny nose. A couple of days later, white spots may appear in the mouth and throat followed by a red spotty rash that appears on the face and continues to the trunk and extremities. Though that may not sound too terrible, there are complications that can arise from the case of measles such as ear infections, pneumonia or diarrhea. More serious complications that can be associated with measles are respiratory failure, inflammation to the brain (encephalitis) and death. The encephalitis may further cause blindness, deafness and developmental disabilities.

Measles has also been associated with immune amnesia where measles damages your immune system and inherently making you more vulnerable to many other illnesses. Measles can be very problematic for pregnant women as the measles can be passed on to the fetus/newborn and may either cause a miscarriage or blindness or deafness. Lastly, measles has been linked to neurological damage that manifests many years later.

This data can be found from literature published decades ago, before there was a vaccine available. At that time, most children got measles. Globally, there were known to be 30 million cases of measles each year and 2.6 million deaths due to the virus! Now, the majority of people of a certain age have been inoculated against the measles infection in North America and other first world countries. Thankfully, the death rate from measles is much lower now due to the vaccine as well as the better medications to treat the complications that may arise along with better methods to control fever than we had long ago.  It is important to note that though we can help control the fever much better, the encephalitis and deafness/blindness associated with measles can occur so rapidly that it is therefore difficult to prevent.

Though there are many of us that have been inoculated against measles, there are increasing numbers of unvaccinated individuals that are at risk of getting measles which is why we are seeing the numbers of measles cases on the rise and risking its elimination status. For those that did receive a two-dose series decades ago, it has been shown to still be effective. For those born before 1970, it is presumed that you have acquired a natural immunity against measles. That being said, if you are planning to travel outside of Canada, it is suggested to receive a booster dose of the measles vaccine.

In the case of susceptible health care workers and military personnel, they should consider a two-dose series of the vaccine to ensure they are well protected. Many people may have travelled during their recent spring breaks to areas with increasing numbers of measles cases such as Florida and Quebec and may have been exposed to measles unknowingly.

Stay tuned for thoughts on why fewer people are vaccinated against measles and what that might mean going forward.

For more information on this or any other health related topic, contact your pharmacist.