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Measles outbreak 2019: America threatens to lose the status of "measles free"



My father, like many of his generation, is hard-of-hearing, and he is pretty sure that a childhood shrub with measles in Canada is to blame. Measles, the most contagious virus known to man, can also lead to blindness, brain swelling, mental disability and, in rare cases, death.

But most people who grew up in Canada and the United States after introducing a vaccine in 1963 did not have to worry about it. In 1978, the US health authorities relied on the elimination of the virus. As more and more people were vaccinated, the measles cases declined. By the year 2000, the US was declared free of lasers, and until recently, the disease was largely banned in North America.

Well, that is changing. Too many people have forgotten how serious the measles are, and they refrain from using vaccines. That's why we all have to worry about measles again. At the beginning of September, US Centers for Disease Control and Prevention had more than 1,200 cases of measles. This is the highest number since 1992. This is also a huge increase compared to 2018, when 372 cases were reported.

As a result, the US could lose its status of measles removal on October 2nd. This status is awarded to countries without continuous transmission of measles for at least one year, during which time all measles cases can be attributed to a traveler who brought the virus from another location where it was in circulation. When an outbreak in New York celebrates its one-year anniversary in early October, our exclusionary status will go along with it.

America is certainly not alone. The number of measles is increasing worldwide and other countries – including the United Kingdom, Greece and Brazil – have lost their eligibility status in the last year.

So, we are falling back on this public health measure, not quite the pre-vaccine world where our parents and grandparents were suffering from measles – but we are heading in that direction. Here's how that happened and why it matters.

Why America's Status Is Measured Without Measles

Before measles vaccine was introduced in the US, there were 4 million cases in the US with 48,000 hospital admissions and 500 deaths each year. Measles were also one of the most common causes of death for children worldwide (and, as people in my father's generation know too well, a major cause of acquired hearing loss).

The beauty of the vaccine is that most people who receive the right dose will never get measles, even when exposed. And by the year 2000, the virus was declared eliminated in the US due to the widespread vaccine. "If the transmission continues in New York, the elimination status for measles will end if a measles case is related to this outbreak on or after October," a CDC spokesman told Vox.

More than 75 percent of the more than 1,200 cases this year are due to New York, where measles patients still appear in the counties of Rockland and Wyoming. Although a similar outbreak in New York City is officially over and the number of cases reported in the state has declined in recent weeks, "some are actually newer cases," the spokesman said. And right now, state health officials are still fighting to control the outbreak.

How did we get here? The CDC points to travelers who infiltrate the virus into dense, under-vaccinated communities. These communities are coherent and conservative. They speak the same languages ​​and read or see the same news. If the vaccine dubiously spreads, it can spread like wildfire. "We believe these communities are more similar," said Nancy Messonnier, director of CDC's National Center for Immunization and Respiratory Diseases in March, and her insularity is helping "escalate outbreaks."

In the case of the state of New York. The outbreak goes back to Ukraine, where 50,000 measles occurred last year. The current theory is that a boy from Israel was infected with the virus by another Israeli who traveled to the Ukraine. When the boy visited the US, he took the virus to the Orthodox Jewish community of New York, where a significant number of people reject immunization for safety reasons.

After that, "there were several imports during the eruption in the communities that kept the outbreaks going," the CDC spokesman said.

Thus, America's outbreaks began this year, as in all the years after the elimination of measles, with a traveler. However, as vaccine coverage rates continue to fall in communities in the US, enough people could be infected with the virus, causing outbreaks to come back on their own.

Some vaccine experts saw this coming – and they said health officials had not done enough to prevent it.

To understand why, look at New York: even though the state's measles coverage rate for measles in 2017 was extremely high -2018 – at 97.2 percent-enough people refused immunization in these close-knit Orthodox Jewish Communities so that the highly contagious virus spread like wildfire.

This phenomenon – the formation of vaccine clusters – has been observed by researchers over the years. In 2017, Peter Hotez, professor and dean of the National School of Tropical Medicine at Baylor College of Medicine, was about to make a comeback, also because of the many hotspots across the country with high rates of unvaccinated people.

The article now looks pretty forward-looking. "Our national leaders consistently pointed to nationwide averages of [vaccine coverage]," Hotez told me recently. "I said who cares – this is not the way measles works – in these bags we see a large number of children who have not been vaccinated [that matter]."

With measles, about 95 percent of people in a community need to be vaccinated In order to prevent the spread of the disease, so-called herd immunity.When enough people are vaccinated, even those are protected from the virus that can not be vaccinated or have not been vaccinated.This 95-percent number is unusually high, because Measles are so contagious. (Other, less communicable diseases, such as polio, require only a coverage rate of about 80 percent.)

This means that even a small, and especially a large, vaccine coverage error can help make the virus easy

Saad Omer, a vaccine researcher and director of the Yale Institute for Global Health, also published a few years ago a warning of a resurgence of measles. In a 2016 scientific study, he predicted major outbreaks by showing how national child immunization rates fell short of the number of children who were actually susceptible to measles.

"If you look at people who are not fully vaccinated, or who are too young to be vaccinated, or [who lose immunity following childhood cancer]then those rates will pile up," Omer said in an interview. And they were worrisome enough that Omer and his colleagues warned that these overlooked groups of children with measles vulnerability "should express concerns that the transmission of endemic measles could be restored despite the overall high level of immunity."

Unfortunately, health officials have not done so. Follow these warnings, the researchers argue. "What should have been done is a coherent national response to strengthening and developing the evidence base to address and increase the acceptance of vaccines," Omer said. But that did not happen.

Hotez agrees. "My feeling is that our nation has not taken the necessary steps to disarm this new anti-vaccine movement. That means measles will become a new normal again.

It certainly does not help that state-level vaccine-relieving parents in many places find it too easy to avoid vaccines by offering religious and philosophical exceptions (ie reasons) that has nothing to do with legitimate medical concerns). And across the country, children can receive "conditional access" to the school, even without any exemption, with the promise of being vaccinated, but the schools do not always care to follow suit.

That was part of New York history until this year's outbreak saw a raid. The school year 2019-2020 is the first school year in which religious exceptions for vaccines are no longer offered. Therefore, all children who come to school must start vaccines in the first weeks of schooling and prove that they are fully vaccinated by the end of the school year. The new law makes New York the fifth state in the nation to eliminate non-medical vaccine exemptions. So many other states still have much to do.

Measles could be "the canary in the coal mine".

If the New York outbreak lasts until October, losing the status of measles elimination will be a blow to public health.

The eradication of measles required decades of work. "It was a confirmation that our immune system works really well," said Hotez. "The fact that measles are back is a worrying sign that there is a national problem in our immune system that there has been a collapse."

"There is a line in the sand," said Alison Buttenheim, a researcher at the University of Pennsylvania. Back to the measles regularly circulating in the country.

In this case, we need to worry about the virus again in our communities. But even if America manages to maintain its elimination status this year, we must ask ourselves if our children are in schools where vaccination rates are high enough, and we must think about measles when traveling with newborns or family members who can not be vaccinated. (Hotez said he got a booster to make sure he was up to date, and anyone worried about the measles vaccine status can have a blood test done to make sure they have antibodies to the virus

It may be that America will regain measles soon, and this does not lead to a complete recovery of the disease.

On the other hand, measles could also be a signal for a bigger problem. Since it is high on the list of infectious diseases, cases can already occur with a small decrease in vaccination rates. Even with other less infectious diseases, the vaccination rates required for herd immunity are much lower, said Walter Orenstein, a professor of infectious diseases at the Emory University School of Medicine. "Measles could be the canary in the coal mine when it comes to identifying a major problem with under-immunization. If this continues to worsen, there is potential. it can mean other diseases are experiencing a comeback. "


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