The measles virus was down. Now he is ready for a return



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BTowards the beginning of this century, before the damage caused by Andrew Wakefield's demystified study linking measles vaccine to autism and social networking sites undermined the disruptive power of opponents to the vaccine, some experts thought that the world was ready to get rid of measles once and for all.

Nowadays, with massive epidemics in the Philippines and Ukraine, more than 80,000 cases in Europe last year and ongoing epidemics in New York, Washington, Texas, Illinois and California, measles does not look like an endangered virus.

There is less talk of measles eradication in 2019. In fact, the projections for the future of measles are much darker now than they were at the beginning. Experts sadly admit that more measles, no less, appear to be looming on the horizon, at least in the short term.

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"I think it's almost a certainty," said Dr. Art Reingold, professor of infectious disease epidemiology at the School of Public Health at the University of California at Berkeley.

Reingold has dedicated more than a decade to the scientific organizations that advise the World Health Organization and the Centers for Disease Control and Prevention on immunization policy and has a perfect command of the efficacy and safety profiles of vaccines. Seeing the measles effort in the wrong direction is a real frustration, he said. "But I'm not smart enough to know what the answer is," he told STAT.

Dr. Nancy Messonnier, Director of the CDC's Center for Immunization and Respiratory Diseases, said that recent increases in the number of measles cases – after years of very low numbers in the United States – mark a "new normal".

Messonnier is not worried that the United States is headed for a time of hundreds of thousands of cases each year and about 500 deaths by complications. Despite the attention that the noisy anti-vaccination movement manages to generate itself, the conditions here are not ripe for this kind of regression.

"In general, at the national level, most Americans are vaccinated and these are the pockets of people who are not vaccinated," she said.

Nevertheless, Messonnier and others predict more regular epidemics in these groups of vulnerable children.

The tragedy is that it does not have to be like that.

Measles could be eradicated. Future generations of children could be spared both measles infections and, possibly, measles immunization once the viruses have been declared extinct.

Experts believe that the measles vaccine is effective enough to do the job. The measles component of the MMR vaccine – which also protects against mumps and rubella – prevents infection in 97 out of 100 children who receive the two recommended doses. If enough children were vaccinated with MMR vaccine worldwide, measles would track smallpox in history books.

The problem is that epidemics continue to occur. Like the current outbreak in New York involving orthodox Jewish families. Or the huge mass that has sickened more than 66,000 people in Madagascar in the past six months, making nearly 900 children.

In some parts of the world – the poorest countries in political conflict – immunization programs are not efficient enough to vaccinate all or most children.

In rich countries, the problem is different: parents choose, for religious or philosophical reasons, not to vaccinate their children against measles.

Whatever the reason, the result is the same. Measles is the viral equivalent of a heat seeking missile. If it circulates or enters an area where there are susceptible children, it will find them and infect them.

A combination of factors makes this virus a real infectious machine. Here is how it works.
Alex Hogan / STAT

Parents who strongly refuse to vaccinate their children because they believe that vaccines cause autism or other harms, and those who delay immunization because of these discredited concerns create clusters of sensitive children. These clusters dig holes in the wall of the herd's immune system that supports public health to fight diseases such as measles.

These pockets of unprotected children are like a little wood. An American who is infected abroad and returns home sick can actually put an end to this conflagration. The more intense the ignition, the greater the resulting fire.

This is exactly what happened during the ongoing outbreak in New York, caused by an unvaccinated child from the Orthodox Jewish community who visited Israel and became infected. To date, there have been 181 cases in this outbreak. Israel's epidemic is due to the explosive spread of measles in Ukraine.

This is also probably what happened in 2015 when 147 children from several states were infected during the spread of the virus to Disneyland California. A child from the Canadian province of Quebec was also infected in the park. He or she was a member of a religious community that does not vaccinate; the outbreak that occurred in Quebec affected 159 people.

That's what the measles virus does.

"The epidemics that occur in Europe, South America or elsewhere, are on a plane," said John Wiesman, Washington State Secretary of Health, who is battling an outbreak. which would probably have happened somewhere in Eastern Europe. "And with travel to today's world, in terms of health safety, we in our own communities need to make sure we do not have pockets of non-immune children."


To date, 74 cases have been reported in the Washington outbreak. Efforts to control it cost the state more than $ 1 million.

Public health officials have struggled to prioritize the eradication of measles – partly because of the difficulty in getting rid of other diseases. Nearly 40 years after its declaration of eradication, smallpox remains the only human disease eradicated by the action of man.

The repeated and unexpected failures that resulted in the polio eradication program, which was now 19 years old, already represented for years the idea of ​​a new goal of polio eradication. ;eradication.

In the early 2000s, while people were hoping that polio eradication was in sight, talking about measles control was gaining ground. There has never been an official measles eradication program, such as those trying to stop polio or guinea worm. Nevertheless, some preparatory work has been done.

The six regions of the WHO said that the elimination of measles was a goal. Only one country, the Americas, was declared free from endemic measles in 2016.

Dr. William Moss, who spent seven years in a working group on measles and rubella that advises the strategic advisory group of experts on immunization from the World Health Organization , sits on a committee that is preparing a discussion paper on measles eradication for the 2020 world meeting. Health Assembly, the annual meeting of WHO member countries.

He would not say what direction he is taking, but admitted that he did not personally think that a boost to eradicate measles was at stake at the moment.

"To be honest, I do not see a goal set for the next five years," said Moss, professor of infectious disease epidemiology at Johns Hopkins University and executive director of the International Center for Disease Control and Disease. Access to vaccines. "What I really see are other intermediate milestones being established. And then, at a later date, the question is raised again. Maybe it's 2025. I'm not sure. "

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