At the weekend the World Health Organization (WHO) declared an outbreak of Ebola in the Democratic Republic of the Congo (DRC) a “public health emergency of international concern”. This designation is the highest alarm level the WHO has to notify its member states about a health crisis that is considered extraordinary, has multi-country risk and requires a coordinated international response. Usually, the director general, Dr Tedros Adhanom Ghebreyesus, would convene a meeting of international health experts to discuss whether an outbreak meets the legal criteria, but for the first time in the agency’s history, he went ahead and declared it after consulting the governments of the DRC and Uganda, and analysing the data presented.

So what is happening now and why are health experts so concerned? We recently learned that there are several hundred suspected cases and 131 suspected deaths from Ebola in the eastern part of the DRC and possibly neighbouring Uganda. Ebola is one of the world’s most deadly infectious diseases, with symptoms progressing from fever and vomiting to internal bleeding and organ failure.

Most of the 16 previous outbreaks of Ebola in the DRC have been caused by the Zaire variant. For Zaire, we have a highly effective vaccine, targeted therapeutics and rapid diagnostics. Unfortunately, this latest outbreak is of the Bundibugyo........

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