Pandemiology Watch (November 26-December 2, 2025)
Emerging outbreaks
Ebola.
On December 1, 2025, the World Health Organization announced that the Democratic Republic of the Congo had declared the end of its 16th Ebola outbreak after 42 days with no new cases since the last infection was reported on October 19. WHO says health authorities will continue strengthened surveillance to detect any potential new cases
Marburg virus.
On December 1, 2025, CIDRAP reported that the Marburg virus disease outbreak in southern Ethiopia has caused eight deaths among 12 confirmed cases. Confirmed cases and close contacts are being monitored, while the World Health Organization (WHO) and local health agencies continue to strengthen surveillance and infection‑control measures
H5N1
U.S.
As of December 2, the Centers for Disease Control and Prevention reports has not reported any cases of person-to-person transmission of H5N1 in the United States. The total remains at 71 confirmed human cases and two deaths.
MEASLES
U.S.
On December 3, 2025, CIDRAP reported that measles outbreaks in Utah and Arizona are continuing to grow. Utah now has 102 confirmed cases, including several students at a local high school, while Arizona has reported additional cases concentrated in Mohave County.
As of November 26, 2025, Center for Disease Control reports a total of 1,798 confirmed measles cases in the U.S. in 2025. 12 % of cases have required hospitalization (212 cases of 1,798), and three deaths have been reported.
Canada.
As of December 1, 2025, Canada has reported 5,262 measles cases where 71% occurred in children, according to the Public Health Agency of Canada. Ontario accounts for 46% of the cases, followed by Alberta with 38%. 89% were unvaccinated, and 7% required hospitalization. Genotype D8 remains the most frequently detected strain. 2 deaths have been reported.
MPOX
Africa.
Sierra Leone: The World Health Organization (WHO) reported 5,442 confirmed mpox cases as of October 26, and no new data have been released in the past week.
Uganda: As of November 23, 2025, Uganda reported 7,054 confirmed mpox cases, according to the World Health Organization. This is an increase of 47 cases since November 2. No new data from WHO have been reported for the past week.
Guinea: As of November 9, 2025, The World Health Organization has reported 1,169 cases in 2025 and one death in Guinea. This is an increase of 34 cases since November 2. No new data from WHO have been reported for the past week.
Rift Valley Fever
Senegal.
Africa CDC has not published any new reports between November 26 and December 2. The most recent Africa CDC update from November 22 reported 11,936 suspected cases, 463 confirmed cases, and 31 deaths in Senegal. Most cases occurred in the Saint Louis region, with 65% in males and 19% in people aged 20–25.
Mauritania.
Africa CDC has not published any new reports between November 26 and December 2. The most recent Africa CDC update from November 22 reported 227 suspected cases, 49 confirmed cases, and 15 deaths in Mauritania. Of the reported cases, 77% were male, and 94% were in individuals aged 10 or over.
POLIO
There were no new updates on poliovirus detections between November 26 and December 2, 2025 on the Global Polio Eradication Initiative. The most recent update, from November 19, 2025, reported detections in Pakistan, Germany, and Papua New Guinea, as well as cases and environmental detections in Chad, Djibouti, and Nigeria.