China reported the first human case of a new avian flu virus. A four-year-old boy who was in contact with chickens and crows raised at home contracted the H3N8 strain of the flu
The Chinese National Health Commission in a press release stated that the possibility of human-to-human transmission is very low. The boy from Henan district exhibited symptoms on April 5.
This is the very first case of the H3N8 strain transmitting from birds to humans. Common in horses and dogs, this strain has even been found in seals. Whole genome sequencing of the virus in the boy found that the H3N8 virus in the current case is a combination of genes that have earlier been detected in poultry and wild birds.
China has a huge population of farmed and wild birds of different species that provides an ideal environment for the viruses to thrive as well as spillover into humans and mutate. Those who work with poultry are normally susceptible to being infected by the viruses. There are a few sporadic incidents in the country. Last year, they reported the first human case of H10N3.
Experts told the Guardian that there is a need for increased surveillance regarding this virus as this is 'reassortant'- combination of genes that could make it easier for it to spread into humans in the future. With the devastating effects of the SARS-CoV-2 virus, which was also a zoonotic virus whose source of origin is still being debated, scientists have chosen to adopt the precuationary tone. Even the World Health Organisation and the Food And Agriculture Organisation is looking into this current case.
China is not the only country that sees a prevalence of outbreaks of bird flu and human transmission. At the beginning of 2022, India, United States and the United Kingdom witnessed several outbreaks among birds. India even reported the H5Nx virus in a boy in Haryana that led to his death.
While 50 countries have reported poultry being infected by this virus, India along with Bangladesh, China, Egypt, Indonesia, and Vietnam are said to be endemic for the virus. Considered to be highly pathogenic among birds, the virus is deadly even for birds.
What Is Bird Flu?
India reported an outbreak of bird flu in poultry as well as crows in January 2021. The influenza A virus that causes bird flu is categorised as avian because wild birds are natural hosts of this sub-type. Classified on the basis of the protein on its surface, Influenza A has 18 HA subtypes and 11 NA subtypes.
H5N1 is the most rampant Avian Influenza virus. So far, only H1N1- swine flu and H3N2- which was also first found in pigs, are the Influenza A sub-types known to adversely affect humans. H5N1 was first recorded in China in 1996 in geese but its first human transmission was reported in 1997 at a outbreak in Hong Kong.
The H3N8 virus found in the four-year-old boy was first isolated in Miami in 1963 and later spready tot North and South America and Europe, leading to massive outbreaks during 1964 and 1965. It has also been suggested to be a possible cause for the 1889-1890 pandemic in humans but there is not enough concrete evidence pointing towards the same.
Bird Flu In Humans
As shared earlier, only close to 700 human cases of bird flu have been recorded, yet. However, the mortality rate of human bird flu infections is very high.
Although human to human transmission is rare, there have been a few cases of outbreaks across Asia and Africa but they have been contained and the communities have recovered.
Children between the ages of 10-19 are the ones most at risk of being infected and their mortality rate due to bird flu is higher than the other age groups. Individuals under the age of 40 working with poultry and not taking precautions are susceptible to the virus.
Some signs and symptoms include atypical presentations of fever and diarrhoea before pneumonia, multi-organ failure, encephalitis, and septic shock. The only way to reduce exposure of the virus to humans is through precautionary measures.
People working on poultry farms should wear Personal Protective Equipment (PPE) kits while tackling with infected poultry. The Food Safety and Standards Authority of India had also released a series of guidelines that should be followed by people consuming poultry when the outbreak was reported in the country. Also
