by What is Bird Flu?
Avian influenza, commonly known as bird flu, refers to a group of influenza viruses that primarily affect birds. While many viruses are low pathogenic, meaning they only cause mild symptoms or no symptoms in birds, some strains can be highly pathogenic and cause severe disease that spreads rapidly through poultry flocks. The highly pathogenic viruses are adapted to spread easily between birds but rarely spread from birds to humans. However, several subtypes of bird flu viruses, such as H5N1, H7N9, and H9N2, have been reported to cause human infection and even death in some cases.
History and Spread of Bird Flu Viruses
The first known major outbreaks of highly pathogenic avian influenza in poultry occurred in the late 1990s when the H5N1 virus was detected in Hong Kong chickens. Mass culling helped contain the outbreak then. Since 2003, however, H5N1 spread across Asia, Europe, and Africa through migratory wild bird routes and poultry trade and affected both domestic and wild birds. As of 2022, H5N1 continues to circulate in poultry in over 60 countries and cause sporadic human infections. Another strain, H7N9, was first reported infecting humans in China in 2013. It has caused several waves of human infections through regular outbreaks in poultry. H9N2 is a more common virus that has been detected in parts of Asia and the Middle East for decades. It occasionally causes mild human infections. These highly pathogenic viruses continue spreading silently among bird populations worldwide through various mechanisms.
Human Health Risks of Bird Flu
While the risk of viruses spreading easily between humans remains low, the repeated spillover events from Bird Flu are concerning from a pandemic potential perspective. Most human infections with strains like H5N1, H7N9, and H9N2 have occurred due to direct or close contact with infected live or dead poultry. However, according to the World Health Organization (WHO), as the viruses circulate longer in poultry, they could accumulate mutations that enable more sustained spread from person to person. This would significantly increase the risk of a pandemic. So far, H5N1 is the most lethal strain and has caused deaths in over 50% of the reported human cases. H7N9 and H9N2 typically lead to milder illnesses in humans. Still, their changing genetic makeup is closely monitored to evaluate the pandemic risk. Crowded living conditions common in many parts pose increased risks of disease emergence and spread.
Mitigating the Pandemic Threat from Bird Flu
There is no single solution for tackling the pandemic threat from emerging flu viruses at the animal-human interface. Coordinated global efforts are required across sectors. Improving surveillance systems to quickly detect outbreaks in poultry and unusual human cases helps assess the risks and mount timely responses. Culling infected poultry flocks, movement restrictions, disinfection, and vaccination (where applicable) are essential containment strategies. Reducing opportunities for contact between domestic poultry, wild birds, and humans through biosecurity methods in the poultry industry and farms can block transmission routes. Raising awareness about avoiding sick or dead wild birds helps reduce spillover risks in communities surrounded by wetlands or migratory flyways. Stockpiling antivirals and developing universal flu vaccines offer viable mitigation against future pandemics. Multisectoral collaborations bring complementary strengths for curtailing pandemics at the source. Ongoing research aids understanding of viral evolution, risk factors, diagnostics, and control tools.
Heightened Global Response Amid Ongoing Threat
International health organizations stress the need for increased global coordination and capacity building to prepare for potential pandemics due to animal flu viruses. WHO efforts include the Global Influenza Surveillance and Response System, which functions through a network of 148 National Influenza Centers in 114 countries for monitoring, research, and information sharing. These mechanisms help detect genetic changes in circulating animal flu viruses of pandemic potential, aid risk assessment and response decision making. The United States and several other countries have prioritized developing universal flu vaccines and stockpiling antiviral drugs Tamiflu and Xofluza. Support programs help low and middle-income nations strengthen surveillance, diagnosis, and disease control capacities. While the avian flu crisis shows no signs of abating yet, a calibrated global strategy holds promise to mitigate impacts of future pandemics through early prevention and preparedness. Rigorous multisectoral approaches in human, animal and environmental health domains are imperative.
As evident from the discussion, bird flu pandemics pose grave risks to human health security worldwide with no geographic boundaries. Continued vigilance and cooperation against known viral strains in addition to preparedness for unknown future threats remain top priorities. Concerted global action to curb the spread at the animal-human interface and facilitate rapid response holds the key to lowering risks from these emerging flu viruses in the coming years
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1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
