Israel has identified its first case of the more aggressive Clade 1b strain of mpox, commonly known as monkeypox, in a traveler returning from abroad, the Health Ministry said, as officials warn of a prolonged shortage of vaccines.
The ministry confirmed that the case was detected last week in a passenger who returned to Israel, with no additional cases identified so far. Israeli health officials believe the patient arrived from the United Arab Emirates, where evidence points to ongoing community transmission of the strain.
Clade 1b, a relatively new subvariant, has driven a major outbreak in parts of central Africa and is considered more virulent than earlier strains. However, experts in Israel say severe illness and death are expected to remain rare under Western health care conditions.
“Although this strain has shown higher severity in Africa, we estimate that in the Western world rates of severe disease and mortality will be significantly lower, likely below 1%,” said Dr. Roi Zucker, an infectious disease specialist and chair of Israel’s Association for LGBTQ Medicine.
Still, Zucker warned that Israel must remain on high alert, particularly because vaccine supplies have been unavailable for more than six months. He stressed that people who have already received two doses do not currently need an additional vaccination, but those who have not been vaccinated remain at risk. The vaccine does not provide full protection but significantly reduces disease severity, he said.
Most mpox infections recorded so far have occurred among men who have sex with men. Mpox is a contagious viral disease related to smallpox and typically causes a rash, often in the genital, anal and oral areas, along with flu-like symptoms. Illness usually lasts two to four weeks and can spread through close physical contact, including contact with lesions, bodily fluids or contaminated objects.
The current global outbreak began about four years ago with a different subvariant, Clade 2b. In 2024 and 2025, Clade 1b spread widely in Africa, with sustained person-to-person transmission. While initially confined to endemic regions, cases have since been detected worldwide, largely among travelers and their close contacts.
Health officials say the United Arab Emirates stands out as an exception, with signs of ongoing community transmission for about a year, based on repeated detections in travelers returning to multiple countries.
Israeli health authorities say there is still uncertainty about the clinical characteristics of Clade 1b in Western countries due to the relatively small number of cases. Data so far suggest the strain is associated with more widespread rashes, a higher number of lesions and more frequent involvement of mucous membranes compared with earlier variants. Reports from Africa have also pointed to pregnancy-related complications and increased respiratory symptoms.
The Health Ministry said it is closely monitoring developments in Israel and abroad and is working to restore vaccine supplies and improve access for at-risk groups.
“Last week a case of Clade 1b mpox was identified in a returning traveler, with no additional cases at this stage,” the ministry said in a statement. “The ministry is taking steps to renew vaccine stock and make it available to populations at risk.”