Pandemiology Watch (October 15-21, 2025)
Rift Valley Fever
Senegal.
On October 14, Africa CDC (Africa Centres for Disease Control and Prevention) reported a total of 132 confirmed Rift Valley Fever cases in Senegal, including 76 new cases since the previous update. In addition, 539 suspected cases have been reported.
Ebola
Democratic Republic of the Congo.
The World Health Organization announced on October 19, 2025, that the last Ebola patient in the Democratic Republic of the Congo has recovered, marking the start of a 42-day countdown to declare the outbreak over. In total, 64 cases (53 confirmed, 11 probable) and 45 deaths were reported since the outbreak began on September 4 in Kasai Province.
MPOX
U.S.
On October 17, 2025, the California Department of Public Health confirmed three cases of clade I mpox in Southern California residents with no recent international travel, marking the first community spread in the state. All patients are recovering, and vaccination is recommended for high-risk groups.
Africa.
Sierra Leone: The latest update from the World Health Organization shows 5,428 confirmed mpox cases as of October 12, a surge of 23 cases since October 5. According to the most recent report from Africa CDC on October 14, the outbreak was linked to clade 2b. Among confirmed cases, 6.5% were in children under 15 years and 52% in males, with a 77% positivity rate.
Uganda: As of October 12, 2025, Uganda reported 6,896 confirmed mpox cases, according to the World Health Organization. This is an increase of 2 cases since October 5. Testing shows a 48,31% positivity rate.
Guinea: As of October 12, 2025, The World Health Organization has reported 1,057 cases in 2025 and one death in Guinea. This is an increase of 6 cases since October 5. Testing shows a 42% positivity rate, and the outbreak is linked to clade 2b.
MEASLES
Israel.
The Israeli Ministry of Health reported on October 10, 2025, that a 1-year-old child has died from measles in Jerusalem, marking the seventh fatality in the ongoing outbreak.
U.S.
As of October 15, 2025, Center for Disease Control reports a total of 1,596 confirmed measles cases in the U.S. in 2025. 12 % of cases have required hospitalization (193 cases of 1,563), and three deaths have been reported.
Olmsted County Public Health Services in Minnesota confirmed a measles case on October 17, 2025, in an unvaccinated child under five with recent international travel.
As of October 15, 2025, South Carolina has confirmed 5 new measles cases, bringing the total in the state to 16 since July 2025, mostly linked to a cluster in Spartanburg County schools with low vaccination rates, according to CIDRAP. Health authorities report that all new patients were quarantined to prevent further spread.
Canada.
As of October 20, 2025, Canada has reported 5,090 measles cases where 70% occurred in children, according to the Public Health Agency of Canada. Ontario accounts for 47% of the cases, followed by Alberta with 38%. 88% were unvaccinated, and 7% required hospitalization. Genotype D8 remains the most frequently detected strain. 1 death has been reported.
POLIO
As of October 16, the Global Polio Eradication Initiative reports new poliovirus detections, including one WPV1 case in Afghanistan, 32 WPV1-positive environmental samples in Pakistan, one cVDPV1 case in Lao PDR, and in Africa, one cVDPV2 case in Angola, one cVDPV2-positive environmental sample in Algeria, and two cVDPV2 cases with two cVDPV2-positive environmental samples in Nigeria.
H5N1
Cambodia
The Cambodian Ministry of Health announced on October 17, 2025, that a 3-year-old girl from Kampong Speu Province has been confirmed as the country’s 16th human case of H5N1 avian influenza in 2025, according to Afludiary.
U.S.
As of October 21, Centers for Disease Control and Prevention has not reported any cases of person-to-person transmission of H5N1 in the United States. The total remains at 70 confirmed human cases and one death.