DR Congo suffers deadliest week in its Ebola outbreak

The Ebola outbreak in the Democratic Republic of Congo (DRC) tracked its highest weekly death toll last week, with more than 300 new deaths. The outbreak, centered in centered in Ituri province, has now grown to 5,514 cases and 2,642 deaths caused by the Bundibugyo strain of Ebola. 

The outbreak continues to be the fastest-growing in history, and has now recorded seven times more deaths than the 2014-2016 West African Ebola outbreak in the first three months of transmission. The West African outbreak was the deadliest in history, taking the lives of more than 11,000 over a two-plus-year period. 

The case-fatality rate of the current outbreak is between 40% and 60% in different health zones, a reflection of patients dying outside of healthcare centers or seeking treatment too late in the course of their infection. There are no approved vaccines or therapeutics against the Bundibugyo strain, though several are currently being trialed in the DRC, Canada, and the United Kingdom (see new data below). 

Last week, the World Health Organization held its second meeting of the IHR (International Health Regulations) emergency committee to formally make recommendations for the DRC and neighboring countries, including more protocols concerning mass gatherings.

The IHR advised postponement of mass gatherings in areas with ongoing community transmission and enactment of measures to reduce crowding in food and drink establishments and nightclubs. The committee also discussed new protocols to implement measures limiting the number of passengers on motorbikes to one and measures for the safe opening of schools.

2 small studies show promise for a monoclonal antibody

In scientific news, reports published yesterday in Nature Medicine detail post-exposure prevention with MBP134, an experimental monoclonal antibody cocktail following Bundibugyo virus disease (BVD) exposure in an adult and four children. 

The adult had been vaccinated against Ebola-Zaire, but the children were unvaccinated and received MBP134 five to six days after high-to intermediate-risk occupational or household exposure to BVD. This marks the first recorded time the drug has been used for post-exposure prevention. 

Throughout the 21-day monitoring period, all family members remained free of clinical or laboratory evidence of BVD.

“Throughout the 21-day monitoring period, all family members remained free of clinical or laboratory evidence of BVD,” the authors said. 

In a second report in the same journal, a 39-year-old healthcare worker who acquired BVD while working in Ituri province was evacuated to Germany and treated with both MBP134 and the antiviral drug remdesivir. 

“Viral RNA concentrations were highest in oropharyngeal swabs and plasma, and became undetectable in blood, throat swabs, urine, and stool by day 13 after symptom onset and in semen by day 25,” the authors wrote. “The patient recovered and was discharged on day 22 after symptom onset.”

MBP134 is pan-Ebolavirus monoclonal antibody developed by Mapp Biopharmaceuticals. Remdesivir has been used for hospitalized COVID-19 patients. Both drugs are currently being trialed in the DRC.