Mpox, WHO counts 1,066 cases in 37 countries in April and awaits emergency vaccine stockpile

This morning the Health section was occupied by the Bundibugyo Ebola outbreak in Congo. This afternoon brings a second dossier from the World Health Organization, on a different and more geographically widespread emergency: mpox.

The news currently comes from a single source (the external situation report No. 66 from WHO on the multi-country mpox outbreak); no independent confirmation available. It is, however, an institutional primary source, that is, the surveillance document itself and not a report about it.

The numbers. The report, published on May 31, 2026, refers to data for the month of April: 1,066 confirmed cases in 37 countries and three deaths, with a case fatality rate of 0.3% among confirmed cases. 62% of April’s cases were reported in the WHO African region.

Item	Figure (April 2026)
Confirmed cases	1,066
Countries with confirmed cases	37
Deaths	3
Case fatality rate among confirmed	0.3%
Share in the African region	62%

Where cases are growing. Three WHO regions — South-East Asia, Western Pacific and Eastern Mediterranean — recorded an increase in confirmed cases in April compared to March 2026. This is the signal the document highlights: the concentration remains African, while the upward movement concerns different areas.

The report also flags an outbreak in Sindh province, Pakistan, which affected newborns and infants: 29 confirmed cases and eight deaths in March 2026. Within a global picture showing a 0.3% case fatality rate among confirmed cases, a cluster with eight deaths out of twenty-nine confirmations indicates a population affected under conditions very different from the average.

The stated limits of interpretation. This is surveillance data, not a study: it counts only cases confirmed by laboratory and reported to authorities, and therefore depends on each country’s diagnostic capacity and the timeliness of reporting. The report is also dated: published on May 31 with data referring to April, it provides a picture several months behind the present. The document does not provide, in the available material, the cumulative total of the outbreak nor the breakdown by viral clades.

The vaccine chapter. WHO and its partners expect the emergency stockpile of mpox vaccines, managed by the International Coordinating Group, to become operational by August 2026 — that is, by this month. The mechanism is the one already used for other diseases with epidemic potential: a centralized reserve that countries can request according to established criteria, instead of bilateral negotiations with manufacturers. This newspaper does not issue health recommendations: we report the forecast contained in the organization’s document, without usage indications and without statements on product efficacy, which the report does not address in this section.

What to verify. Two elements have a concrete deadline and are verifiable from public sources: the actual coming into operation of the stockpile by the end of August, and the data in the next situation report, which will show whether the increase recorded in the three Asian and Middle Eastern regions continued beyond April. On the Pakistani outbreak, the document does not indicate whether transmission has been interrupted.