Progress in vaccinating children against measles has slowed in LMICs
Although pediatric measles vaccine coverage has largely improved globally over the past decade, more than half of low- and middle-income countries included in a study published in Nature experienced slowed progress, researchers reported.
Alyssa N. Sbarra, MPH, a researcher at the University of Washington’s Institute for Health Metrics and Evaluation, and colleagues assessed trends in routine first-dose measles-containing vaccine (MCV1) administration in 101 low- and middle-income countries (LMICs) — where more than 99% of measles cases and deaths still occur — from 2000 through 2019.
According to their study, MCV1 coverage among children living in an LMIC increased from 65.6% (95% uncertainty interval [UI], 64.2%-75.2%) in 2010 to 81% (95% UI, 79.2%-82.7%) in 2019, far short of the herd immunity target of at least 95% coverage. The authors reported that vaccination rates increased at a national level in 69.9% of countries (95% UI, 64.4%-75.2%) from 2010 to 2019.
According to the researchers, further gains are required to reach the Global Vaccine Action Plan (GVAP) targeted coverage goals of 80% and 95% in countries and districts, respectively.
Researchers from the CDC and WHO recently reported that more than 207,000 people died globally as a result of measles in 2019 as cases hit a 23-year high.
“As the world responds to the COVID-19 pandemic, it's going to be vital to address these pre-existing gaps in coverage, while also making sure that children missed during the pandemic receive their necessary immunizations," Sbarra said in a press release. "If that doesn't happen, the pandemic will compound the existing weaknesses in immunization systems and put more children at risk for measles."
In 2000, the lowest MCV1 coverage areas were located in Hari Rasu, Ethiopia (4%; 95% UI, 1.1%-9.7%), Gabi Rasu, Ethiopia (4.8%; 95% UI, 1.4%-11.4%) and Isa, Nigeria (4.9%; 95% UI, 1.5%-10.8%). During this time, 60 districts had coverage rates below 10%.
In 2019, the three lowest MCV1 coverage areas were all in Afghanistan — Poruns (9.2%; 95% UI 2%-25.5%), Wama (12.1; 95% UI, 2.8%-32.6%) and Waygal (12.7%; 95% UI, 3%-34.2%).
In 2000, 38.4% of districts had a high probability of reaching the GVAP target of 80% coverage, whereas in 2019 the number remained “stagnant” at 33.2.%, the researchers said.
“These community-level analyses of where children are and are not being vaccinated help pinpoint the areas of greatest vulnerability before the start of the pandemic," Sbarra said.
The authors also compared vaccination status in urban and rural settings and found that, in 2019, MCV1 coverage was lower among children living in remote rural areas compared with children living in remote urban areas — 33.3% vs. 15.2% unvaccinated. The authors said more unvaccinated children live in urban location (47.9% of all unvaccinated children) compared with those in remote rural areas (16% of all unvaccinated).
“Policymakers need to target both urban and remote rural locations in order to equitably vaccinate all children," Sbarra said.