Health officials in Cambodia have confirmed the country’s first case of human infection with avian influenza A(H5N1) for . A 30-year-old man from Kampot province tested positive for the virus, prompting investigations into the source of the infection and preventative measures to protect the community.
The patient, residing in Meanrith village of Tuek Chhou district, developed symptoms including fever, cough, and abdominal pain, according to a statement released by the Ministry of Health on . Fortunately, he has made a full recovery and returned home after receiving intensive care from a medical team.
Understanding H5N1 Avian Influenza
H5N1 influenza, commonly known as bird flu, is a viral infection that primarily affects birds. While it typically doesn’t spread easily to humans, occasional human infections can occur following direct contact with infected poultry or contaminated environments. Symptoms in humans often mimic those of seasonal influenza, including fever, cough, and potentially more severe respiratory illness.
The virus has been detected in Cambodia since , initially affecting wild birds. Between and , no human cases were reported in the country. However, the virus re-emerged in humans in , and since then, a total of 27 human cases have been reported as of (six in 2023, ten in 2024, and eleven in 2025), with 12 proving fatal. Notably, seventeen of these cases occurred in children under the age of 18.
Source of Infection and Public Health Response
Investigations into the recent case revealed a potential link between the man’s infection and exposure to dead poultry. Dead chickens were found at his home, and these were consumed approximately three days before the onset of his illness. This finding reinforces the known transmission pathway of H5N1, where the virus typically spreads between birds but can occasionally infect humans through direct contact with infected poultry or contaminated environments.
Health authorities are actively working to determine the origin of the infection and are examining individuals who may have been in contact with the patient. This proactive approach aims to prevent further spread within the community. As a preventative measure, the antiviral drug Tamiflu (oseltamivir) has been distributed to those who had direct contact with the infected man, a standard protocol in Cambodia following H5N1 detections.
Global Context and Risk Assessment
The current case in Cambodia occurs within a broader global context of H5N1 circulation. Avian influenza A(H5N1) is circulating in wild birds, poultry, and some mammals around the world. While occasional human infections are expected, the World Health Organization (WHO) currently assesses the risk to the general population as low. However, for those occupationally exposed to the virus, such as farm workers, the risk is considered low to moderate, depending on the preventative measures in place.
Another strain, clade 2.3.4.4b, has gained international attention since due to its global spread and increasing number of infections in mammals, including humans. We see not yet known which strain was involved in the latest case in Cambodia, though it is likely clade 2.3.2.1c, a variant that is endemic in the country.
Importance of Surveillance and Prevention
This case underscores the ongoing risk of zoonotic diseases – diseases that can spread between animals and humans – and the importance of continued surveillance. Early detection and prompt medical intervention, as demonstrated in this instance with the patient’s full recovery, are crucial for managing H5N1 infections effectively.
Public health officials emphasize the importance of avoiding contact with sick or dead poultry. Thoroughly cooking poultry and eggs can also help to eliminate the virus. Individuals working with poultry should practice good hygiene, including frequent handwashing, and wear appropriate protective equipment.
The WHO routinely reassesses the risk posed by H5N1 to factor in new information and provide updated guidance to member states. Continued monitoring of the virus’s evolution and spread is essential for protecting public health.
