The World Health Organisation's Europe chief has warned that monkeypox cases in the region have tripled in the last two weeks and urged countries to do more to ensure the previously rare disease does not become entrenched on the continent.
Hans Kluge said in a statement that increased efforts were needed despite the United Nations health agency's decision last week that the escalating outbreak did not yet warrant being declared a global health emergency.
"Urgent and coordinated action is imperative if we are to turn a corner in the race to reverse the ongoing spread of this disease," Kluge said.
More than 5000 monkeypox cases have been reported from 51 countries worldwide, according to the US Centers for Disease Control and Prevention.
Kluge said the number of infections in Europe represents about 90 per cent of the global total, noting that 31 countries in the WHO's European region have identified cases.
Kluge said data reported to the WHO show that 99 per cent of cases have been in men - and that the majority of those have been in men that have sex with men.
But he said there were now "small numbers" of cases among household contacts, including children.
Most people reported symptoms including a rash, fever, fatigue, muscle pain, vomiting and chills.
Scientists warn anyone who is in close physical contact with someone who has monkeypox or their clothing or bedsheets is at risk of infection, regardless of their sexual orientation.
Vulnerable populations like children and pregnant women are thought to be more likely to suffer severe disease.
About 10 per cent of patients were hospitalised for treatment or to be isolated, and one person was admitted to an intensive care unit.
No deaths have been reported.
Kluge said the problem of stigmatisation in some countries might make some people wary of seeking health care and said the WHO was working with partners including organisers of gay pride events.
In the United Kingdom, which has the biggest monkeypox outbreak beyond Africa, officials have noted the disease is spreading in "defined sexual networks of gay, bisexual or men who have sex with men".
UK health authorities said there were no signs suggesting sustained transmission beyond those populations.
A leading WHO adviser said in May that the spike in cases in Europe was likely tied to sexual activity by men at two rave parties in Spain and Belgium, speculating that its appearance in the gay and bisexual community was a "random event".
UK experts have said most cases in the country involve men who reported having sex with other men in venues such as saunas and sex clubs.
Ahead of gay pride events in the UK this weekend, London's top public health doctor asked people who have symptoms of monkeypox, like swollen glands or blisters, to stay home.
WHO Europe director Kluge appealed to countries to scale up their surveillance and genetic sequencing capacities for monkeypox so that cases could be quickly identified and measures taken to prevent further transmission.
He said the procurement of vaccines "must apply the principles of equity".
The main vaccine being used against monkeypox was originally developed for smallpox and the European Medicines Agency said earlier this week it was beginning to evaluate whether the shot should be authorised for monkeypox.
The WHO has said supplies of the vaccine, made by Bavarian Nordic, are extremely limited.
Some countries including the UK and Germany have already begun vaccinating people at high-risk of monkeypox; the UK recently widened its immunisation program to offer the shot to mostly gay and bisexual men who have multiple sexual partners and are thought to be most vulnerable.
Until May, monkeypox had never been known to cause large outbreaks beyond central and west Africa, where the disease is endemic in several countries and mostly causes limited outbreaks when it jumps to people from infected wild animals.
To date, there have been about 1800 suspected monkeypox cases including more than 70 deaths in Africa.
Vaccines have never been used to stop monkeypox outbreaks in Africa.
The WHO's Africa office said this week that countries with vaccine supplies "are mainly reserving them for their own populations".
Australian Associated Press
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