To date, more than 5,000 cases of monkeypox have been reported from 51 countries worldwide that are not endemic for the disease, according to the US Centers for Disease Control and Prevention. The number of infections in Europe accounts for around 90 per cent of the global total, with the UK reporting 1,235 cases – the highest on the continent. Researchers from Chelsea & Westminster Hospital NHS Foundation Trust looked at 54 patients who attended four sexual health clinics in London and were diagnosed with monkeypox during a 12-day period in May 2022. Of the 54 patients, all but two of the patients were unaware that they had been in contact with a known case, and none reported travel to sub-Saharan Africa, but many had recently visited other European countries. All patients identified as men who have sex with men, and 47 of 52 reported at least one new sexual partner during the three weeks before symptoms, and 49 of 52 reported inconsistent condom use during the same time period. More than half of the patients had more than five sexual partners in the 12 weeks before their smallpox diagnosis. Patients were all symptomatic and had skin lesions – 94 percent of patients had at least one skin lesion on the genital or perianal skin. Mostly the patients had a mild illness and recovered in isolation at home, but five people required admission to hospital because of pain or infection of the skin lesions. All improved and were discharged with a median hospital stay of seven days. “The frequently observed symptom of skin lesions in the anus and penile area, and the fact that a quarter of patients tested positive for gonorrhea or chlamydia at the same time as monkeypox infection, suggests that transmission of monkeypox virus in this cohort is seen skin-to-skin, for example in the context of sexual activity,” said Dr. Ruth Byrne, from the Trust. He added that “it is possible that at various stages of infection, monkeypox mimics common STIs, such as herpes and syphilis, in its presentation. It is important that sexual health practitioners and patients are aware of the symptoms of monkeypox as misdiagnosis of the infection may prevent the opportunity for appropriate intervention and prevention of further transmission.” The study also noted significant differences in the clinical characteristics of this cohort compared to previous outbreaks reported from previous outbreaks in other countries. A smaller proportion of patients in this cohort reported feeling weak and tired and/or had a fever than in case studies in previous outbreaks. In addition, 18 percent (10/54) of patients in this cohort reported no early symptoms before the onset of skin lesions. “Given the proposed route of infection through contact during sexual activity and the number of clinical findings that differ from previous descriptions, we suggest revising the case definitions detailing symptoms such as acute febrile illness to better accommodate the current findings, as At least one in six of this cohort would not meet the current definition of a ‘probable case’,” said Dr Nicolo Girometti, from the Trust. The researchers also predict that the high prevalence of genital skin lesions in patients and the high rate of coexisting sexually transmitted infections means that sexual health clinics are likely to see additional cases of monkeypox in the future. However, the team cautioned that their findings may not be representative of the overall epidemic. They said it is important to remain alert to the possibility of spread to other groups while balancing targeted health promotion in groups disproportionately affected by the current epidemic. 20220703-164204
