Washington D.C. 9 August 2024 (PAHO/WHO) – In an epidemiological alert released on 8 August, the Pan American Health Organization (PAHO) has called on countries of the Americas to strengthen surveillance, including laboratory detection and genomic sequencing of confirmed cases, following the identification of a new variant of mpox virus, Clade I (Clade Ib), in the sub-Saharan African Region. While the new variant has not been reported in the Americas, countries should remain alert to possible imported cases.
The new variant is associated with sustained transmission, as well as the occurrence of cases in a wider range of age groups than during previous outbreaks, including children. It is estimated to have emerged in the Democratic Republic of the Congo in September 2023 and is associated with a significant increase of cases in the country.
Mpox is a viral illness caused by the monkeypox virus, a species of the genus Orthopoxvirus. Two different clades exist: clade I and clade II. Symptoms include fever, intense headache, muscle aches, back pain, low energy, swollen lymph nodes, and a skin rash or mucosal lesions. The rash tends to be concentrated on the face, palms of the hands, and soles of the feet, but can also be found on the mouth, anogenital region, and eyes. Symptoms typically last between 2 to 4 weeks and go away on their own without treatment.
Since the beginning of 2024 (to 26 July 2024), the Democratic Republic of Congo Ministry of Health reported 14,479 cases of mpox, and 455 deaths. According to the report, “the number of cases reported in the first six months of this year match the number reported in all of last year.” Children under the age of 15 accounted for 66% of cases and 82% of deaths. Cases of the new variant have also been reported in Rwanda, Uganda and Kenya. Testing is also underway in Burundi to determine whether reported cases in that country are also due to the new variant.
As a result of the hike in cases, on 7 August the World Health Organization (WHO) Director General, Dr. Tedros Adhanom Ghebreyesus announced that he will convene a panel of experts to advise him on whether the expanding outbreak constitutes a global health emergency.
While no cases of the new variant have been reported in the Americas, PAHO recommends that countries of the Americas remain vigilant to the possibility of introduction in the region.
In the Americas, 62,752 mpox cases were reported by 31 countries and territories between 2022 and 1 July 2024, including 141 deaths. To date, only clade II has been detected in the region. Most cases were identified through HIV patient care services, sexual health services, or primary health care facilities and involved primarily, though not exclusively, men who have sex with men. The epidemiological alert urges country health authorities “to continue surveillance based on laboratory testing and timely reporting of confirmed and probable cases.” Genomic surveillance is also key to determine the circulating clades and their evolution.
Possible cases of mpox should avoid contact with others and seek testing to confirm diagnosis, followed by clinical management of symptoms.
In the alert, PAHO reminds Member States that efforts should focus on “early detection and diagnosis, isolation and contact tracing.” While vaccination can help prevent infection for people at risk, “mass vaccination against mpox is neither required nor recommended”.
PAHO also recommends the dissemination of public health messages to inform and educate target populations, including health personnel and populations with the highest prevalence of HIV and other sexually transmitted infections (STIs), primarily, though not exclusively, men who have sex with men, to improve early recognition of signs and symptoms.
On 23 July 2022, the WHO Director General determined that the multi-country outbreak of mpox constituted a public health emergency of international concern (PHEIC). The number of cases reported globally peaked in August 2022 and began a steady decline until April 2023. On 11 May 2023, following a significant reduction in global spread, the Director General determined that the event no longer constituted a PHEIC.
Mpox remains a global public health concern, with cases and outbreaks still being reported worldwide. In June 2024, 26 countries reported over 930 cases and 4 deaths globally.
