Measles outbreak in 2019: the year announces very bad for measles

Measles was eliminated in the United States in 2000. And yet, progress in the fight against the disease has collapsed to a staggering degree, especially this year.

According to the latest measles figures provided by the Centers for Disease Control and Prevention, between 1 January and 11 April, 555 cases of measles were reported in 20 states. In the past week alone, 90 cases have been reported to the CDC, mainly in the state of New York.

This means that there have already been more cases of measles in 2019 than any year in the last five years. And as we are only in April, we are on track to break the record for the largest number of cases in the United States since the elimination of the disease two decades ago.

CDC

So, what is the driving force behind the rise? The outbreaks that occurred here were concentrated in four states: New York, New Jersey, Washington and California. And of these, the vast majority of cases (more than 460) occurred in Orthodox Jewish communities in New York and the suburbs of Rockland. There, a minority of community members who are skeptical about vaccination have decided not to vaccinate on behalf of their children, which has resulted in lower immunization rates and created a space for the spread of the virus. very contagious.

"More than 70 of the 90 cases [in the last week] were from New York and New York, "said Amanda Cohn, CDC Senior Advisor for Vaccines," and the majority of them have been since April 1. So it's an epidemic that is accelerating. "

But to really understand what's happening with measles in the United States, you have to step back and look at the global situation.

All of the major epidemics here are related to travelers who have brought the virus back to the United States from countries where the epidemic is still ongoing, including Ukraine, the Philippines and Israel. It is a reminder of the close dependence of our health on this disease. people even in far-off countries, especially when we do not use the tools to prevent the spread of diseases, such as vaccines.

A global push of measles

In the past two years, measles cases have risen slightly in several countries around the world, with a 300% increase in measles cases over the same period in 2018, according to the World Health Organization. According to WHO, Ukraine, Madagascar, India, Pakistan, the Philippines, Yemen and Brazil are among the most affected countries.

Malagasy health authorities have recorded more than 69,000 cases of measles and 1,200 deaths related to the largest measles outbreak ever on the island. Ukraine has experienced 72,000 cases and the Philippines 19,000.

The reasons for the epidemics vary from one country to another – from the refusal of the vaccine to problems of access to health care or vaccines, to civil unrest and lack of awareness of the need. to vaccinate. But what all these causes have in common: these factors lower the vaccination coverage rate.

And in places where there was very little measles before, as in the US, skepticism about vaccines seems to be a common factor, Cohn said. "The reluctance to vaccinate in a world where people no longer see measles. We must continue to remind people of how serious measles is.

How measles spreads in areas with high vaccination coverage

The measles virus is indeed one of the most infectious diseases known to man. A person with measles can cough in a room and leave, and a few hours later, if you are not vaccinated, you can catch the virus by the droplets in the air that the infected person has left behind. No other virus can do it.

The good news is that the measles, mumps and rubella vaccine is incredibly effective at keeping measles from spreading. But almost all members of a community must be vaccinated to obtain what is called "collective immunity".

For a vaccine to be effective, it takes a certain percentage of people in a population to be immunized. This prevents diseases from spreading through populations and even protects people who are not or can not be vaccinated, such as newborns and people allergic to the vaccine. For measles, 90 to 95% of the population must be vaccinated. It's almost everyone in a community.

In total, 91% of young American children received the MMR vaccine in 2016, according to the latest data from the CDC. This is sufficient for the immunity of the flock. But national statistics hide geographical groups within states where many people are not vaccinated. And it's in these communities – from New York to Washington – where the virus is taking off.

When travelers do not get vaccinated in these hot spots and bring the virus back to the under-vaccinated communities in the United States, it is not difficult for measles to start spreading.

For one disease to be considered eliminated, all cases of measles must be related to a case imported from another country. Cohn, CDC, said that was still the case with the measles outbreaks here.

"That being said," she added, "the outbreak in New York and the state of New York is worrying just because of the length of time that this transmission has occurred. If these cases persist for a long time, we may not be able to link all cases to the imported case.

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