Amid COVID, H5N6 bird flu case now reported in China: What is it? What are the symptoms?

The H5N6 Bird Flu is regarded as one of the most dangerous strains of Avian Influenza to have been found over the years, in poultry flocks or in captured dead wild birds. Between June 18 and 24, no new cases of human infection with avian influenza A(H5N6) virus were reported to WHO in the Western Pacific Region. A total of 32 laboratory-confirmed cases of human infection with influenza A(H5N6) virus including 19 deaths have been reported to WHO in the Western Pacific Region since 2014. The last case was reported from China, with an onset date of May 13 this year.

A Chinese state-run news agency CCTV reported on Thursday that a man in the southwestern Sichuan province had been hospitalised after contracting the H5N6 variant of the avian flu. The 55-year-old man was hospitalised in Bazhong city after running a fever and subsequently testing positive for the highly pathogenic virus. Following that, local officials had activated an emergency response and sterilized the area. The report cited unnamed experts saying that the risk of large-scale transmission of the H5N6 variant of the virus among humans was low. The report did not provide further details.

What is the H5N6 bird flu? Details on avian influenza

Avian influenza refers to the disease caused by infection with avian (bird) influenza (flu) Type A viruses. These viruses occur naturally among wild aquatic birds worldwide and can infect domestic poultry and other bird and animal species. Avian flu viruses do not normally infect humans. 

Rare human infections with some avian viruses have most often occurred after unprotected contact with infected birds or surfaces contaminated with avian influenza viruses. However, some infections have been identified where direct contact was not known to have occurred. Illness in people has ranged from mild to severe.

The spread of avian influenza A viruses from one infected person to another has been reported very rarely, and when it has been reported it has been limited, inefficient and not sustained. However, because of the possibility that avian influenza A viruses could change and gain the ability to spread easily between people, monitoring for human infection and person-to-person spread is extremely important for public health.

Symptoms of the Avian Influenza (H5N6)

Symptoms begin within two to eight days after contracting the virus and can seem like the common flu. Cough, fever, sore throat, muscle aches, headache and shortness of breath are common symptoms observed.

The reported symptoms of Avian Influenza (H5N6) in humans have ranged from

• Mild to severe fever
• Conjunctivitis
• Influenza-like illness
• Nausea 
• Abdominal Pain
• Diarrhoea
• Acute Respiratory diseases 
• Viral Pneumonia
• Neurological Changes

Avian Influenza in humans cannot be diagnosed by clinical signs and symptoms, rather laboratory testing is needed. A swab from the upper respiratory tract (nose or throat) of the sick person must be collected and used to determine the positivity or negativity of the virus.

Whenever avian influenza viruses are circulating in poultry, there is a risk for sporadic infection and small clusters of human cases due to exposure to infected poultry or contaminated environments. Therefore, sporadic human cases are not unexpected. With continued incidence of avian influenza due to existing and new influenza A(H5) viruses in poultry, there is a need to remain vigilant in the animal and public health sectors.

Community awareness of the potential dangers for human health is essential to prevent infection in humans. Surveillance should be continued to detect human cases and early changes in transmissibility and infectivity of the viruses.

Image Credits - PTI