Influenza A and B viruses cause seasonal epidemics in humans. The first case of human infection with avian influenza virus from livestock has been detected in the United States. Health
The World Health Organization (WHO) reported on Tuesday the first laboratory-confirmed case of human infection with influenza A(H5N1) virus from livestock. WHO informed the national focal point for the implementation of the International Health Regulations (IHR) of the United States of America about this.
The Texas patient, who worked on a farm with cows suspected of being infected with the avian influenza virus, became symptomatic on March 27. This is the first case of human infection with the A(H5N1) virus acquired through contact with infected cattle, and the second confirmed case of influenza A(H5N1) identified in the United States. No other cases of human infection with influenza A(H5N1) have yet been identified.
Because the virus has not acquired mutations that would facilitate transmission among humans, WHO assesses the public health risk associated with the virus as low, and for those with occupational exposure as infection is considered moderate.
Influenza A viruses usually circulate among animals but can also infect humans. Infection in humans mainly occurs through direct contact with infected animals or a contaminated environment. Depending on the original host, influenza A viruses can be classified as avian influenza viruses, swine influenza viruses, or other types of animal influenza viruses. Avian influenza virus infections in humans can cause mild upper respiratory tract illnesses to more severe illnesses that can be fatal.
Influenza A and B viruses cause seasonal epidemics among humans. Moreover, according to modern scientific data, only type A viruses can cause a global pandemic. Influenza A viruses are found in many animal species. The emergence of an influenza A virus strain capable of infecting humans and being persistently transmitted from person to person could cause an influenza pandemic.
The primary natural host of most subtypes of influenza A viruses is wild waterfowl. Outbreaks of avian influenza in poultry have immediate and serious negative consequences for the agricultural sector. situations in public health, including sanitary and epidemiological ones. Under the IHR, countries are required to notify WHO and other countries of events identified by their national surveillance system.