China has confirmed the first instance of human infection from H10N3, a rare strain of a virus that normally infects poultry.

Recently, the National Health Commission of Beijing reported that a 41-year-old man in the eastern Jiangsu province had been infected with the rare strain.

 What do we know so far about H10N3?

• According to the Food and Agriculture Organisation (FAO), this virus appears to be rare in birds and does not cause severe disease. So far little is known about this virus.
• The World Health Organization (WHO) said while the source of the patient’s exposure to the H10N3 virus was not known and no other cases were found among the local population, there was no indication of human-to-human transmission
• The Beijing-based National Health Commission said the strain has low pathogenesis among birds, implying that the virus did not spread easily among poultry and was likely to be restricted to limited populations.

Yet avian influenza viruses that have little impact on birds can be much more serious in people, such as the H7N9 strain that killed almost 300 people in China during the winter of 2016-2017.

What is avian influenza?

H5N1 is the most common virus causing bird flu, or avian influenza.

• Though largely restricted to birds, and often fatal to them, it can cross over to other animals, as well as humans.
• According to the WHO, the H5N1 was first discovered in humans in 1997 and has killed almost 60% of those infected.
• Though it is not known to transmit easily among humans, the risk remains.

Why are bird flu viruses a cause of concern?

Speculation about the origin of the SARS-CoV-2 has heightened worries about animal- and bird-borne viruses.

• The emergence of new strains, particularly among domesticated animals and birds, is a story of evolution and inevitability, and sporadic reports of new viruses infecting humans abound.
• An outbreak of the H5N8 virus in birds led to hundreds of thousands of poultry being culled in various European countries.
• In February, Russia reported that seven poultry workers in a plant were infected by the H5N8 strain. All of them recovered.
• India, too, faced an outbreak of the virus in flocks of poultry in January and undertook culling.

Source: The Hindu