The monkeypox virus may be spreading 'undetected', said the World Health Organisation even as the global confirmed cases rise to more than 550 from 30 countries that are not endemic to the virus.
While, so far, most cases have been reported among men who have sex with men presenting with symptoms at sexual health clinics, "the sudden appearance of monkeypox in many countries at the same time suggests there may have been undetected transmission for some time," said WHO Director-General Tedros Adhanom Ghebreyesus, in a statement.
The virus may have been transmitted for months or years undetected though investigations are ongoing and there are clear no answers yet, added Dr. Rosamund Lewis, the WHO's monkeypox technical lead, during a news conference in Geneva.
"We don't really know whether it's too late to contain. What WHO and all member states are trying to do is prevent onward spread," Lewis said. Contact tracing and isolating patients who have monkeypox are crucial to stopping the spread, she said.
Earlier the WHO had refuted the need to avoid LGBTQ+ parades, as the virus itself is not a sexually transmitted infection, which are generally spread through semen and vaginal fluids.
"These communities are working hard to inform their members about the risks of monkeypox, and prevent transmission," Ghebreyesus said, adding the need to "work hard to fight stigma".
He noted that stigma against the LGBTQ+ community could "prevent infected individuals from seeking care, making it harder to stop transmission".
The global health body has also urged affected countries to widen their surveillance, to look for cases in the broader community.
Monkeypox has not previously been described as a sexually transmitted infection, but it can be passed on by direct contact during sex.
Anyone can be infected with monkeypox if they have close physical contact with someone else who is infected.
"The situation is evolving, and we expect that more cases will continue to be found," the WHO chief said.
While monkeypox symptoms resolve on their own, it "can also be severe in some cases".
Ghebreyesus said that the WHO is working to provide accurate information to those groups most at risk of monkeypox; to prevent further spread among at-risk groups; to protect frontline health workers; as well as to advance understanding of this disease.
Meanwhile, even as some countries are racing to stockpile smallpox vaccines against monkeypox, the WHO has not recommended mass vaccination.
But, the WHO is working with companies to increase access to those new vaccines and treatments, Lewis said.