It may seem as though danger from the Ebola epidemic is gone, but new research from the Bloomberg School of Public Health (JHSPH) suggests otherwise. The study, led by Justin Lessler and released in the March 13 issue of Science, found that disruptions to the West African health care, caused by the Ebola crisis, have led to a significant decrease in vaccinations and a consequent increase in susceptibility to a variety of other diseases.
Ebola is a virus which causes fever, vomiting and bleeding and is deadly in many cases. It is transmitted to humans by animals, but spreads through a population by close physical contact. There have been outbreaks of Ebola in the past, but according to the World Health Organization (WHO), the 2014 outbreak was by far the largest and most complex. It started in December of 2013 in Guinea, but quickly spread to Liberia and Sierra Leone, causing a total of 21,000 cases and 8,400 confirmed deaths in West Africa alone.
Rates of Ebola have been declining in recent months, but as Lessler’s research shows, the delayed and indirect effects could be worse than the disease itself. The chaos caused by the Ebola crisis forced many health care facilities to close and caused people to avoid those that were open in fear of contracting the disease. This means that many people did not receive routine vaccines for common diseases. In recent decades, campaigns promoting vaccination in West Africa have led to large declines in diseases such as measles, polio, tuberculosis, influenza, tetanus, HIV and malaria. However, disruptions caused by the Ebola crisis could severely damage that progress.
In particular, Lessler’s team examined the effect on measles, a virus which, according to the WHO, is the leading cause of death among young children worldwide; it caused 145,700 deaths in 2013. The number of deaths from measles has dropped by 75 percent since 2000 because of the widespread use of vaccinations.
The study looked at multiple scenarios, but assuming a 75 percent disruption in health care services over a period of 18 months, Lessler’s research found that there would be a 45 percent increase in the number of children unvaccinated for measles in West Africa. If an outbreak were to occur, the usual number of measles cases would nearly double, and the number of additional deaths would be anywhere from 2,000 to 16,000.
Lessler is concerned that the Ebola epidemic may cause a setback in our control of diseases like measles. He also believes that the effects are not just limited to West Africa. The presence of unvaccinated individuals in Guinea, Liberia and Sierra Leone may mean that bordering countries face the risk of measles outbreaks. As if the death and chaos from Ebola itself was not enough, disruptions to the West African health care system could have long term and widespread deadly effects.
The study offers a solution to this issue. Lessler calls for campaigns across the three countries to target children who likely missed critical vaccinations, such as measles and polio, and ensure that they finally receive their vaccinations. Lessler believes that this could halt the problem of missed vaccinations before it turns into another public health disaster. These diseases may be deadly, but they can be prevented with relatively easy and inexpensive vaccines. As long as those vaccines are distributed and promoted properly, the issue of infectious childhood diseases is entirely manageable.
The Ebola crisis killed thousands in West Africa and spread fear worldwide. Although the direct danger from the disease itself may be in decline, the indirect effects caused by disruption to the health care system of West Africa are not. The research done by Lessler and his team shows just how vital vaccines are to keeping people healthy and aims to increase vaccination in the wake of the Ebola crisis, preventing anymore needless deaths in an already devastated region.
Lessler is a professor of epidemiology at JHSP and conducted the study with department colleagues.
