Just under a month after the confirmation of an outbreak of Marburg virus disease (MVD) in Equatorial Guinea in February 2023, the WHO has issued an update confirming further cases. The statement from WHO suggests that 8 additional laboratory-confirmed cases have been reported, bringing the total to 9 confirmed cases and 20 probably cases since the declaration last month.
“There are seven deaths among the laboratory confirmed, and all probable cases are dead.”
Of particular concern to health experts is the observation that the areas reporting cases are about 150 kilometres apart, which WHO identifies as a suggestion of “wider transmission of the virus”. WHO assess the risk posed by the outbreak as “very high at the national level”, “moderate” on a regional level, and “low” at the global level.
Equatorial Guinea “recommitted” to containment
WHO’s Dr Abdi Mahamud commented on the situation, recognising that this is Equatorial Guinea’s first outbreak of MVD. It is therefore experiencing a steep learning curve but must not be tempted to think it “could go away”. Dr Mahamud stated that the country is “recommitted” to containing the outbreak.
Cross-border and case increase concern
As WHO notes, the three affected provinces have international borders with Cameroon and Gabon. These borders are “very porous”, and although no cases have been reported in these neighbouring countries, the “risk of international spread cannot be ruled out”.
Furthermore, concern has been raised over the communication between the health authorities and WHO. Helen Branswell writes for STAT that WHO “typically issues more frequent updates” but relies on information from the affected countries.
“The length of time between this update and the one that preceded it is notable.”
Branswell’s description of the outbreak as “significantly larger than has previously been acknowledged” conveys a sense of the anxiety around accurate and timely communication. She contrasts this to quick disclosures from Tanzanian officials as the country also grapples with an outbreak.
We will hear more about vaccine development for Marburg and other filoviruses at the World Vaccine Congress in Washington, where there will also be opportunities to explore the importance of surveillance and transparency in disease outbreaks.