Monkeypox experts discussed Thursday whether the World Health Organisation should classify the outbreak as a global health emergency -- the highest alarm it can sound.
A second meeting of the WHO's emergency committee on the virus was held to examine the worsening situation, with nearly 15,400 cases reported from 71 countries, according to the US Centers for Disease Control and Prevention.
A surge in monkeypox infections has been reported since early May outside the West and Central African countries where the disease has long been endemic.
On June 23, the WHO convened an emergency committee of experts to decide if monkeypox constitutes a so-called Public Health Emergency of International Concern (PHEIC) -- the UN health agency's highest alert level.
But a majority advised the WHO's chief Tedros Adhanom Ghebreyesus that the situation, at that point, had not met the threshold.
The second meeting was called with case numbers rising further.
"I need your advice in assessing the immediate and mid-term public health implications," Tedros told the start of the meeting, which lasted more than six hours.
If the committee advises Tedros that the outbreak constitutes a PHEIC, it will propose temporary recommendations on how to better prevent and reduce the spread of the disease and manage the global public health response.
But there is no timetable for when the committee will reach their conclusions from the meeting or make the outcome public.
Ninety-five percent of cases have been transmitted through sexual activity, according to a study of 528 people in 16 countries published in the New England Journal of Medicine -- the largest research to date.
Overall, 98 percent of infected people were gay or bisexual men, and around a third were known to have visited sex-on-site venues such as sex parties or saunas within the previous month.
Tedros said Thursday that this posed a challenge, as in some countries, "the communities affected face life-threatening discrimination".
"There is a very real concern that men who have sex with men could be stigmatised or blamed for the outbreak, making the outbreak much harder to track, and to stop," he told the meeting.
Tedros said the first committee gathering helped delineate the dynamics of the outbreak, but he remained concerned about the number of cases.
Despite an apparent declining trend in some countries, six nations reported their first cases last week.
"As the outbreak develops, it's important to assess the effectiveness of public health interventions in different settings, to better understand what works, and what doesn't," he said.
Tedros also said information coming from endemic countries in Africa was "very scant", making it hard to characterise the situation in the region and design interventions.
A viral infection resembling smallpox and first detected in humans in 1970, monkeypox is less dangerous and contagious than smallpox, which was eradicated in 1980.
The European Centre for Disease Prevention and Control said that as of Monday, 7,896 confirmed cases had been reported from 27 countries in the European Economic Area.
The worst affected were Spain (2,835), Germany (1,924), France (912), the Netherlands (656) and Portugal (515).
"Particular sexual practices are very likely to have facilitated and could further facilitate the transmission of monkeypox among MSM groups," it said.
Danish company Bavarian Nordic is the lone laboratory manufacturing a licensed vaccine against monkeypox and jabs are currently in scarce supply.
Loyce Pace, the assistant secretary for global affairs at the US Department of Health and Human Services, said it was "very hard" for the world to handle monkeypox on top of Covid-19 and other health crises.
"I know it can be scary... and, frankly, exhausting," she told reporters at the US mission in Geneva.
However, "we know a lot more about this disease, we've been able to stop outbreaks previously and we, importantly, have medical counter-measures and other tools available".