Hong Kong records 21 mpox cases since August, high-risk groups urged to get jabs

Hong Kong has recorded 21 cases of mpox since August, accounting for 70 per cent of this year’s total, prompting health authorities to urge people who engage in high-risk sexual contact to take protective measures and get vaccinated to reduce their risk of infection.

The latest case, involving a 29-year-old man, brought the total number recorded in Hong Kong this year to 30, comprising 23 local cases and seven imported ones, the Centre for Health Protection (CHP) said on Saturday. Twenty-one cases, or 70 per cent of the total, were recorded since August.

Epidemiological investigations showed that all 21 patients reported engaging in high-risk sexual behaviour during the incubation period, including having sex with male strangers or multiple partners, and having sex without a condom, the centre said.

Most of the patients had not been vaccinated against mpox, it added.

Genetic analysis of the virus also found that some cases had identical genetic sequences, suggesting they might have shared a common source of infection, with multiple transmission chains existing among the population of men who have sex with men.

“The CHP once again urges individuals who have engaged in high-risk sexual contact, particularly with strangers, to remain vigilant and take appropriate personal protective measures, including receiving the mpox vaccination and avoiding high-risk sexual contact, so as to lower the risk of infection,” it said.

The centre also noted that more than half of the patients diagnosed in recent months with mpox, formerly known as monkeypox, had used dating apps to find casual sexual partners.

“In some cases, patients were unable to contact their newly met sexual partners, which hinders effective contact tracing and the implementation of corresponding prevention and control measures,” it said.

It urged people to keep their sexual partners’ contact details to make contact tracing easier.

The latest case under investigation involved a 29-year-old man who developed a papule – a small, solid, raised bump – on his buttock on September 28. He later developed rashes on his limbs and buttock, as well as a fever and swollen lymph nodes.

He attended an outreach vaccination service organised by the centre on October 8. Staff noticed his symptoms and arranged for him to receive isolation treatment at Princess Margaret Hospital in Kwai Chung. His clinical specimen tested positive for the mpox virus.

The patient was in a stable condition, the centre said.

He had high-risk sexual contact with a man in Hong Kong during the incubation period, it added.

The centre said it was continuing its epidemiological investigation of the case and would report it to the World Health Organization.

Hong Kong has recorded 114 mpox cases – 90 local and 24 imported – since 2022, all involving male patients.

Mpox is a zoonosis – an infectious disease that can be transmitted from animals to humans – caused by the monkeypox virus. Infection can occur through contact with the virus from infected animals or people, or contaminated materials.

People can become infected through bites or scratches from certain wild animals, such as some species of primates, rodents and squirrels, or through direct contact with their body fluids.

Human-to-human transmission is mainly through close contact with infected individuals, such as skin-to-skin, mouth-to-mouth, mouth-to-skin and sexual contact. The likelihood of transmission through respiratory droplets is relatively low.

The Department of Health provides mpox vaccination services for high-risk groups, including people who engage in high-risk sexual practices, such as having multiple sexual partners, sex workers or people who have had a sexually transmitted infection in the past 12 months.