Sunday, July 12, 2026

Cambodian MOH Announces 5th Human H5N1 Case of 2026

 

#19,243

With thanks for the head's up from @FluTrackers, we have the following announcement from Cambodia's Ministry of Health on their 5th confirmed HPAI H5N1 human infection of 2026 - and 39th in just over 3 years - this time involving a 9-month-old girl from Phnom Penh which was confirmed positive on July 9th.

While most infections in Cambodia have been linked to direct or indirect exposure to infected poultry, there is no mention in today's report a suspected source of infection. The investigation, however, is ongoing. 

The MOH announcement, along with the translation, follow:


(Translation)

Kingdom of Cambodia
Nation Religion King
Ministry of Health

Press Release

On Bird flu case in 9-month-old girl

The Ministry of Health of the Kingdom of Cambodia would like to inform the public that there is 1 case of avian influenza in a 9-month-old girl who was confirmed to be positive for the H5N1 avian influenza virus on 9 July 2026 by the National Institute of Public Health and the Pasteur Institute of Cambodia. The patient is a resident of Prek Ta Kong village, Chak Angre Leu commune, Meanchey district, Phnom Penh. The patient has been placed in isolation at the hospital and is receiving intensive medical care.

The emergency response team of the national and sub-national ministries of health has been collaborating with the teams of the provincial agriculture departments and local authorities at all levels to actively investigate the outbreak of bird flu and respond according to technical methods and protocols, find the source of transmission in both animals and humans, and search for suspected cases and contacts to prevent further transmission in the community, as well as distribute Tamiflu to close contacts and conduct health education campaigns among residents in the affected villages.

The Ministry of Health would like to remind all citizens to always pay attention to and be vigilant about bird flu because H5N1 bird flu continues to threaten the health of our citizens. We would also like to inform you that if you have a fever, cough, runny nose, or difficulty breathing and have a history of contact with sick or dead chickens or ducks within 14 days before the onset of symptoms, do not go to gatherings or crowded places and seek consultation and examination and treatment at the nearest health center or hospital immediately. Avoid delaying this, which puts you at high risk of eventual death.

How it is transmitted: H5N1 bird flu is a type of flu that is usually spread from sick birds to other birds, but it can sometimes be spread from birds to humans through close contact with sick or dead birds. Bird flu in humans is a serious illness that requires prompt hospital treatment. Although it is not easily transmitted from person to person, if it mutates, it can be contagious, just like seasonal flu.

How to prevent:

Do not touch or eat sick or dead chickens and wear gloves and a mask or cover your nose with a scarf before handling chickens for food. Then blanch them in boiling water before plucking their feathers.

1/2

Address: Lot No. 80, Samdech Pen Nut Street (289)
Phone: (+855) 23 885 970
Website: www.moh.gov.kh
Sangkat Boeung Kak 2, Khan Toul Kork, Phnom Penh

Email: info@moh.gov.kh

Telegram: t.me/MOHCambodia

In February of 2023 an older clade of H5N1 (2.3.2.1.x) reemerged in Cambodia's population after a 9 year absence, spilling over into 6 humans in 2023, 10 people in 2024, and 18 people in 2025.

Last October Dr. Erik Karlsson (@eakarlsson.bsky.social‬) from the Institut Pasteur du Cambodge, Phnom Penh, Cambodia, - along with a long list of colleagues - published a brief letter in the NEJM on first 16 cases.

Among them were 4 `clusters' (Father/Daughter, two neighbors, 2 siblings, and 2 cousins living in the same household), 6 fatalities, and 12 cases < 18 years of age.

While human-to-human transmission was considered, the available evidence suggests a `shared' exposure instead, with infected poultry the most likely source of infection.
Most of these recent Cambodian cases have been due to a new reassortment of an older clade of the H5N1 virus (recently renamed 2.3.2.1e) - which appears to be spreading rapidly through both wild birds and local poultry.

Although we usually focus on the more dominant H5 2.3.4.4b clade, these cases remind us that there are other lineages of HPAI H5 still in circulation around the globe (see Viruses: Zoonotic Implications of the Co-Circulation of Clade 2.3.4.4b and 2.3.2.1a H5N1 Avian Influenza Viruses in Nepal in 2023), and each is on their own evolutionary trajectory.

In addition to this very active Cambodia lineage of H5N1, some of the other HPAI H5 contenders we continue to follow include:

at