Public health

The fight against measles

3D representation of the measles virus

Alissa Eckert

The goal of eliminating the transmission of measles worldwide by 2020 is far from being achieved. Since 195 countries endorsed this target at the World Health Organization (WHO) health assembly in 2012, the number of measles cases has declined worldwide—its transmission has already been halted in 86 nations. But a large number of people continue to be infected with the virus, a highly contagious disease that causes a high fever, cough, blocked nose, eye irritation, and a red spotty rash. In children and people with weakened immune systems, measles can significantly  compromise immunity and increases the risk of fatal infections. Between January 2013 and December 2017, 634,139 cases of measles were reported worldwide, almost all involving children. The most affected regions were Africa (224,093 cases), East Asia (142,305), and Europe (105,851). Only 1,316 cases were recorded in the Americas, but even this was unexpected, since the region was declared measles-free in 2016. Based on the records for this period, Mikal Patel of the WHO immunization program and Walter Orenstein of Emory University, USA, collected data on vaccine status in 434,956 cases. In 63% (275,754) of the cases, the infection could have been prevented if the child had been given the two recommended doses of the vaccine at the appropriate age (Lancet Global Health, March). Almost half of the remaining 156,384 infections were deemed unpreventable because the children were not yet old enough to have been given the first dose of the vaccine. Northern Brazil has been experiencing a measles outbreak since February 2018 that has so far affected more than 10,300 people, meaning the country will lose the measles-free status that it obtained in 2016.