Daijiworld Media Network - New Delhi
New Delhi, Dec 13: Health authorities in Spain have identified the first confirmed case of human-to-human transmission of mpox clade 1b outside Africa, marking a significant development in the global understanding of the virus’s spread.
Mpox is a viral infection transmitted mainly through close physical contact, particularly skin-to-skin interaction, and is characterised by symptoms such as fever, swollen lymph nodes and skin lesions. Clade 1b, a highly transmissible variant, was first detected during an outbreak in the Democratic Republic of the Congo in 2023.
The case, detailed in the International Journal of Infectious Diseases, involves a 49-year-old man in Madrid who had no history of travel to Africa and had already received two doses of the Imvanex smallpox/mpox vaccine. He visited a clinic on October 10 with a single genital lesion and painful swelling of lymph nodes in the groin.
According to the report, the patient disclosed recent sexual contact with two local partners, neither of whom had travelled to mpox-endemic regions. After ruling out other sexually transmitted infections, doctors confirmed mpox clade 1b through PCR testing of the lesion.
Researchers described the case as unprecedented. They noted that, until now, all reported clade 1b cases outside Africa were linked either to travel to endemic regions or to direct contact with someone who had travelled there. Spanish health authorities confirmed that the patient had no epidemiological link to previously known clade 1b cases in the country.
In Spain, only one other clade 1b case has been reported so far — involving a traveller returning from Tanzania — with no connection to this newly identified infection.
Human-to-human transmission of mpox clade 1b has been sustained in several African countries. The first known case outside Africa was detected earlier in a Swedish traveller returning from an endemic area. Since then, sporadic cases have appeared globally, almost all linked to recent travel or contact with travellers.
Health experts have urged heightened vigilance and preventive measures to limit both clinical and public health impact, particularly among groups considered more vulnerable based on previous outbreaks since 2022. These include people living with HIV, men who have sex with men, and individuals with multiple sexual partners.
According to the World Health Organization’s latest update, 2,501 new confirmed mpox cases — including 12 deaths — were reported from 44 countries in October, underscoring the continued global relevance of monitoring and containment efforts.