Ebola derailed child immunizations in the three countries hardest hit by Ebola — Liberia, Sierra Leone and Guinea, leaving hundreds of thousands more children vulnerable to the more routine infections, researchers said Thursday. Already, worrisome clusters of measles cases are cropping up.
The new study warns that it's crucial to restart the shots quickly, citing math models that estimate thousands could die if a large enough measles outbreak were to strike before the battered health care system has a chance to recover.
Measles epidemics often follow humanitarian crises because "measles is so incredibly contagious," explained Johns Hopkins University epidemiologist Justin Lessler, who led the study published in the journal Science.
"Measles is not the only health threat that has been made worse by the Ebola crisis, and may not even be the most dire, but it is one we can do something about," he added.
The Ebola death milestone announced by the World Health Organization on Thursday had been expected for weeks, even though overall the epidemic is waning. Liberia has begun the 42-day countdown toward being declared Ebola-free if no new cases arise. Guinea and Sierra Leone still are struggling to end new infections, although cases aren't nearly as high as in the fall.
A side effect of hospitals closed in the outbreak zone, and a population frightened of what health care remained, is that unnecessary deaths occurred from malaria, childbirth and other common conditions.
Now the question is whether measles and other vaccine-preventable childhood diseases will be the next post-Ebola problem.
In Guinea, UNICEF has reports of 339 suspected measles cases, 27 of them confirmed, agency spokesman Patrick Moser said in New York.
Doctors Without Borders said it has reports of 182 suspected measles cases in Liberia, plus some suspected cases in Sierra Leone, too.
Health services are slowly resuming in areas where Ebola's grip has lessened. In Liberia, routine childhood vaccinations are being given in health facilities again, said Tolbert Nyenswah, an assistant health minister.
In addition, UNICEF and Doctors Without Borders are working with Liberian officials for a measles and polio vaccination campaign in May that will target more than 600,000 children under age 5, Moser said. Similar campaigns also are planned for Sierra Leone, depending on the continuing Ebola situation.
Measles remains a leading killer of children in developing countries, and it's far more contagious than Ebola. There have been some huge epidemics when vaccinations were disrupted. Hopkins' Lessler noted that between 2010 and 2013, about 294,000 cases of measles spread through the Congo, with more than 5,000 deaths, after a period of political instability.
His team set out to model what might happen if a large measles outbreak spread across Liberia, Sierra Leone and Guinea.
At the start of the Ebola crisis there already were about 778,000 unvaccinated children ages 9 months to 5 years in the three countries, the study estimated. For every month that Ebola disrupted regular health care, an extra 20,000 children became susceptible to measles, the researchers calculated.
In a worst-case regional outbreak, about 127,000 people would have gotten sick before Ebola but, after 18 months of vaccine disruption, an additional 100,000 illnesses could be expected, the researchers calculated. Anywhere from 2,000 to 16,000 more deaths could occur.
That estimate assumed that vaccinations dropped by 75 per cent during the Ebola crisis, and Lessler said recent information suggests the decreases weren't that severe. Even if vaccinations dropped by just 25 per cent, Lessler said that still could mean tens of thousands more illnesses and anywhere from 500 to 4,000 additional deaths than before the recent Ebola outbreak.
Models are just that, and there's no way to know if the region really is poised for a post-Ebola measles outbreak. But health groups say it's urgent to restart vaccinations.
"There is a threat," Dr. Estrella Lasry of Doctors Without Borders said in a phone interview from Liberia.
Health workers will have to make sure parents understand the need for resuming routine childhood immunizations, and the difference from studies of experimental Ebola vaccines that are being conducted in the region.
"There's a need to rebuild trust in the health system," she said.
Associated Press writers Maria Cheng in Geneva and Jonathan Paye-Layleh in Monrovia, Liberia, contributed to this report.