The monkeypox case definition in the UK is broad.

Daniel Pan and colleagues were concerned that the definition of a probable case of monkeypox infection we use at the UK Health Security Agency (UKHSA) is too constrained, resulting in missed diagnoses in the wider community.

Since May 20, 2022, the UKHSA has also included the case definition of possible monkeypox infection in its testing guidance. One of the criteria used to identify possible cases of monkeypox infection is “an illness where the clinician has a suspicion of monkeypox”. This intentionally broad definition is aimed at capturing the scenarios raised by Pan and colleagues. As of Sept 16, 2022, the UKHSA's Rare and Imported Pathogens Laboratory tested more than 650 women and approximately 250 children for monkeypox infection. Women and children are 15% of all people tested; however, where gender is known, 99% of confirmed cases are male adults.

Although Pan and colleagues assert that “Transmission within the community is already taking place”, they do not provide evidence for this statement except for the known transmission within the main at-risk groups. We would urge caution in drawing this conclusion without first doing serological tests in different cohorts or PCR tests, or both.

In short, all clinicians should be aware that the UKHSA's case definitions ensure that anyone with symptoms consistent with monkeypox infection can be tested for it. However, notably, most cases continue to be identified within the subgroups of individuals outlined in the probable case definition. Therefore, targeting public health interventions and case definitions towards these subgroups, while remaining vigilant for a potential wider spread of infection in other subgroups, remains an appropriate course of action.

For more on the UK Health Security Agency's guidance see https://www.gov.uk/guidance/monkeypox-case-definitions