Global efforts to eliminate measles took a step backward, with the number of cases rising to 353,236 in 2018, up 167% from 132,413 cases in 2016.
World Health Assembly leaders announced mixed results of efforts to eliminate measles by 2020, with recent challenges to vaccination taking a toll on progress against the disease, which killed an estimated 142,300 people in 2018.
“We've made progress since 2000—measles cases have declined and measles vaccination coverage has been increasing,” Minal Patel, MD, of the World Health Organization, told Contagion®. “However, recently, we've gone backwards—cases and measles-related deaths are up.”
The Global Vaccine Action Plan, endorsed by all 6 World Health Organization regions in 2012, aims to eliminate measles by 2020. An update on progress toward that goal, published this month in the US Centers for Disease Control and Prevention’s Morbidity and Mortality Weekly Report, shows that incidences of measles increased in 5 WHO regions between 2016 and 2018.
“We've been monitoring this increase in cases since 2016,” Patel told Contagion®. “It's in line with what we know—that the world is not vaccinating everyone who should be vaccinated.”
While the number of reported measles cases decreased 59%, from 853,479 in 2000 to 353,236 in 2018, it is up 167% from 2016, when 132,413 cases were reported. Similarly, incidences of measles decreased 66%, from 145 to 49 cases per million population between 2000 and 2018, but rose 158% from 19 cases per million in 2016.
Immunization coverage increased from 2000 to 2018, reaching 86% global coverage of the first dose of the vaccine (MCV1), up from 72%. Coverage rates remained steady since 2016 in most regions, but fell in the region of the Americas from 92% in 2016 to 88% in 2017 before rising to 90% in 2018. A total of 118 countries achieved ≥90% MCV1 coverage in 2018, up from 86 countries in 2000, but a decrease from 126 countries during 2012—2013.
The second dose of the vaccine (MCV2) was expanded to 171 countries in 2018, up from 98 in 2000, driving an increase in coverage from 18% in 2000 to 69% in 2018.
Estimated deaths from measles fell 73% from 535,600 in 2000 to 142,300 in 2018. The report estimates that vaccination prevented 23.2 million deaths during 2000—18.
“Health care providers should be aware of the symptoms of measles, and they should suspect measles in people who present with fever and rash,” Patel told Contagion®. “They should also understand the importance of their role in stopping cases—that they should report their suspicions to public health immediately as time is of the essence. This publication shows that measles is essentially everywhere—and every health care provider needs to consider measles in their differential diagnosis.”
In 2018, 82 countries reached measles elimination status, with the latest countries to reach the achievement being Austria, Bahrain, North Korea, Oman, Singapore, Switzerland, and Timor-Leste. However, endemic measles transmission was reestablished in Venezuela, Brazil, Albania, Czechia, Greece, and the United Kingdom.
“The global immunization community is developing a new global strategy for the next decade,” Patel told Contagion®. “The new strategy, called the Immunization Agenda 2030, outlines a vision that touches on all aspects of achieving high vaccination coverage with measles (as well as other vaccines), covering issues around access, quality and demand for immunization. If executed in all countries, we'd expect a decline in measles cases and deaths.”
Measles was declared eliminated in the United States in 2001, and the nation held onto that status despite a surge in outbreaks and new cases. Health officials confirmed 1250 cases of measles in 31 states from January 1 to October 3, the most since 1992.
As the frequency of vaccine-preventable diseases increases in the United States, more state legislators have introduced bills to restrict vaccine exemptions in an apparent reversal of an increase in the volume of state legislation introduced to expand exemptions seen in prior research. The number of parents who took advantage of vaccine exemptions increased for the third consecutive year in the 2018-19 school year to 2.5%.