British monkeypox patients are showing symptoms different from previous outbreaks, the first study examining cases in Britain said on Friday, prompting researchers to call for an update to the disease’s definition.
Until just a few months ago, monkeypox was largely confined to west and central Africa, where new outbreaks were mainly caused by humans being infected with the virus from animals such as rodents.
But since May, more than 3,400 cases have been recorded worldwide, the vast majority of them in western Europe among men who have sex with men and have no known links to the cases in sub-Saharan Africa.
The UK detected some of the earliest new global cases, and the first study of patients there was published in The Lancet Infectious Diseases journal on Friday.
Researchers analyzed 54 monkeypox patients in London, all men who have sex with men, accounting for 60 percent of UK cases as of May 26.
All but two were unaware that they had been in contact with someone who had monkeypox.
A quarter of the men were HIV positive and a quarter had a sexually transmitted disease while they had monkeypox.
All patients had skin lesions, 94 percent of them in the genital and anal areas.
These factors suggest the virus is transmitted through skin-to-skin contact, such as during sex, the study said.
The World Health Organization is investigating cases of seeds testing positive for monkeypox, but has claimed the virus is not sexually transmitted and is mainly spread through close contact.
– Less fever, fatigue –
Just 57 per cent of UK cases suffered from a fever, compared with 85-100 per cent of cases in outbreaks earlier this year.
Previous outbreaks also saw many more lesions on the limbs, faces, and necks.
However, in three-quarters of the UK cases, the lesions appeared in just one or two areas, mainly on or around the genitals, the study said.
The UK patients also had mostly mild cases lasting less than three days, with only five being hospitalized.
The study’s lead author, Nicolo Girometti, said the British definition of monkeypox symptoms, which describes it as an acute illness with fever, “should be reviewed to best align it with current knowledge”.
“At least one in six of this cohort would not have met the current definition of ‘likely event’,” said Girometti of the Chelsea and Westminster Hospital NHS Foundation Trust.
Paul Hunter, an infectious disease expert at Britain’s University of East Anglia who was not involved in the study, said he didn’t think Britain needed to change its monkeypox definition as it was currently “very broad”.
Hugh Adler, of the Liverpool School of Tropical Medicine, told AFP that monkeypox, which is spreading around the world, is unlikely to be a new form of the virus because other studies have shown “there hasn’t been massive genetic changes”.
Lesions on the genitals suggest the virus spreads through contact during sex in the UK, while previous African cases may have had lesions on the hands from touching an infected animal or patient, he said.
He added that the study showed that initially, monkeypox can resemble sexually transmitted diseases.
“Any new rash in a man who has sex with men should consider a monkeypox test in the current climate, even if he has no other symptoms,” he added.
#monkeypox #symptoms #previous #outbreaks #study
