Pandemiology Watch (March 19-26, 2025)

H5N1

As of March 24, Centers for Disease Control and Prevention (CDC) has confirmed that no cases of person-to-person transmission of H5N1 have been reported.

H5N1 has been confirmed in a sheep in Yorkshire, UK, with no additional infections in the remaining flock. The case was discovered through routine surveillance after avian influenza was found in captive birds, as reported by the Department for Environment, Food & Rural Affairs and Animal and Plant Health Agency on 24 March 2025.

MEASLES

As of March 20, 2025, Center for Disease Control reports a total of 378 confirmed measles cases in the U.S. in 2025. 17 % of cases are or have been hospitalized (64 cases of 378), and 2 cases have died.

As of March 25, 2025, Texas Department of State Health Services reports 327 cases of measles from this year. This is an increase of 68 from March 14, 2025. The majority of cases are unvaccinated or have unknown vaccination status (325 cases of 327).

The Pan American Health Organization (PAHO) has made a rapid risk assessment, where the public health risk in the Americas for measles has been assessed as HIGH. This is due to amongst other things, the increase in the susceptible population partly because of the low vaccination coverage. 

POLIO

As of March 19 Global Polio Eradication Initiative reports 12 WPV1-positive environmental samples in Pakistan and 6 positive cVDPV2 cases and 8 cVDPV2-positive environmental samples in Africa. Additionally, Yemen reported 4 cVDPV2 cases and one cVDPV2-positive environmental sample.

MPOX

Data from World Health Organization shows MPOX in Uganda plateauing. From March 9 - March 16 there has only been an increase of 35 cases. Since last year, the MPOX clade Ib cases has been surging in the East African country.  

MISCALLANEOUS

No news regarding the unidentified disease in Basankusu, Democratic Republic of the Congo (DRC), or Sudan virus disease in Uganda.