The accidental fatalities of Ebola

It would seem that news of the Ebola virus epidemic is never far from the media. Its spread has been halted and many countries are now free from the virus. However even last month it was reported that Scottish nurse Pauline Cafferkey had been readmitted to hospital for a third time following complications caused by the virus.Ms. Cafferkey initially contracted Ebola while undertaking charity work in Sierra Leone during December 2014.

Ebola had caught the world unawares when it spread across Africa, and there were real concerns about its spread to Europe, the United States and further afield. Its horiffic symptoms and the ease of transmission meant that the world took notice.The rapid spread of the virus prompted Médicins Sans Frontières, the International Red Cross and other charities to provide emergency medical care and aid to the worst affected areas. Importantly there was and still is no known vaccine.

Current figures state that 11,316 people died during the epidemic. However, a further 10,623 died from other diseases attributed to the redistribution of healthcare resources to cope with the demand the virus placed on the existing health system.This number was derived from a model developed by scientists at the Yale University School of Public Health. The model assumed that 50 per cent of resources designated to treat diseases such as malaria were diverted to cope with the outbreak.

The authors of the paper believe this to be an underestimate as in some areas there was only a 10 per cent attendance of those appointments booked prior to the outbreak. Routine childhood vaccinations would also have diminished, as would the distribution of regular prescriptions as people stayed at home to avoid Ebola.

The lack of a vaccine meant that trial drugs were used in the field, and the epidemic acted as a testing ground for experimental drugs and treatments. Since the outbreak, a number of previously developed vaccines have moved to the clinical trial phase. Perhaps the most promising news in vaccine development is the Cytomegalovirus (CMV). The hope is to use CMV as a vector for delivering a vaccine for Ebola. This technique is already used for other vaccines. The virus has the ability to target key sites that are also associated with the Ebola virus, such as the lymphatic system.

Once CMV reaches these sites, it is able to react immediately, making it effective against the rapidly replicating pathogens. CMV is  seen as an effective vector as infection is asymptomatic in the body.

A promising development to tackle the virus by a different mechanism is the discovery of effective antibodies in the blood of an Ebola survivor from a 1995 outbreak.
The mAb114 antibody binds with the Ebola virus, blocking it from interacting with receptor cells. As the virus cannot bind to cells the spread of infection in the body is prevented. In trials the use of the antibody saved the lives of six infected Macaque monkeys, even five days post-infection.

2014 saw the worst epidemic of the Ebola virus in the world; the effects spread far beyond those infected as the redistribution of resources meant people succumbed to diseases they may otherwise have survived.
It is important to look not only at those that suffered directly from the disease, but also from the failure of provisions in general. There are, however, promising new treatments that will help us cope better with another outbreak.

Image: European Commission DG ECHO

Image: European Commission DG ECHO

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