A woman receives a measles, mumps and rubella vaccine at the Rockland County Health Department in Pomona, N.Y. (Seth Wenig/AP)

Measles cases increased 300 percent worldwide in the first three months of 2019 compared to the first three months in 2018, according to the World Health Organization.

The 2019 increase "follows consecutive increases over the past two years,” according to a World Health Organization statement, which added, “While this data is provisional and not yet complete, it indicates a clear trend. Many countries are in the midst of sizeable measles outbreaks, with all regions of the world experiencing sustained rises in cases.”

Measles is preventable by vaccine — but vaccination rates are declining. In part, that’s due to supply problems. In Madagascar, for example, infrastructure provided a challenge, contributing to a measles outbreak earlier this year. Africa had the biggest rise in measles cases — 700 percent compared to the same period in 2018.

But the World Health Organization also named “vaccine hesitancy” as a top global health threat. In North America and Europe, conspiracy theories and misinformation about vaccination have also contributed to the decline.

An outbreak in Ukraine, for example, was blamed in part by Alana Suprun, Ukraine’s acting minister of health, on a lack of political commitment to and public sentiment against vaccination. (In a sign of how interconnected the world and contagious diseases are, an outbreak in Israel was thought to have begun when Orthodox Jewish visitors brought the disease back from a religious trip to Uman, Ukraine.)

In New York City earlier this month, Mayor Bill de Blasio (D) declared an emergency and ordered mandatory vaccinations under threat of fine in Williamsburg, Brooklyn, where measles cases were dramatically increasing, primarily in an ultra Orthodox Jewish community.

The concept of mandatory vaccinations, or variations on that theme, are being used elsewhere, too, in an attempt to stop measles outbreaks. Italian children have been instructed not to appear at school without proof of vaccination, and Italian officials say vaccination rates have improved since the introduction of that rule. This month, the German state of Brandenburg became the first in Germany to introduce compulsory vaccination for children, amid calls for such a rule to be implemented nationwide as the number of measles cases rises.

But increasing accessibility and adding requirements won’t necessarily solve the problem of measles outbreaks. According to the World Health Organization, understanding of vaccinations needs to increase if the number of measles cases is to decrease.

“Responding to measles requires a range of approaches to ensure all children get their vaccines on time, with particular attention to access, quality and affordability of primary care service," the World Health Organization statement said, adding, "It will also take effective public-facing communication and engagement on the critical importance of vaccination, and the dangers of the diseases they prevent.”

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