Date : 28/10/2023

Relevance: GS Paper 3 – Environment and Ecology

Keywords:BAS, HPAI, GSGSSI, Antarctic Region

Context-

In a recent alarming discovery, scientists from the British Antarctic Survey (BAS) have detected Highly Pathogenic Avian Influenza (HPAI) in the Antarctic region for the first time.

This finding, detailed in the Biological Risk Assessment of Highly Pathogenic Avian Influenza in the Southern Ocean, has raised significant concerns about the vulnerable wildlife populations in this remote area. The presence of HPAI, specifically in brown skua populations on Bird Island, South Georgia, indicates a potential threat to penguins, seals, and other avian species. This article delves into the origins, spread, potential consequences, and ongoing efforts to monitor and manage this unprecedented outbreak.

Understanding Influenza A Viruses: Avian and Swine Influenza

Influenza A viruses are classified based on their origin hosts, notably avian influenza (bird flu, subtypes H5N1 and H9N2) and swine influenza (swine flu, subtypes H1N1 and H3N2). These viruses, distinct from human influenza viruses, rarely transmit among humans.

Decoding Flu Virus Names: Hemagglutinin and Neuraminidase

The nomenclature of flu viruses incorporates “H” for hemagglutinin and “N” for neuraminidase, two proteins on the virus surface crucial for entering and exiting host cells. These proteins were the first flu virus components identified, leading to the naming convention.

Reservoir of the Virus: Avian Source

The primary natural reservoir of these influenza A viruses is aquatic birds. These birds typically experience asymptomatic or mild infections, contributing to the persistence of the virus in avian populations. Vigilance and strategic measures are essential to curb potential outbreaks and protect both animal and human health.

Origins and Spread of HPAI in Antarctica

The origins of the HPAI outbreak in Antarctica are believed to be linked to South America, where outbreaks were first reported in 2022. Seabird populations in the Northern Hemisphere were notably affected, sparking concerns among scientists that the virus might extend its reach to the Southern Ocean. Unfortunately, these fears materialized as the virus rapidly spread southwards along the Pacific coast of South America, covering a staggering 6,000 kilometers in just three months. This rapid spread resulted in the infection of 500,000 seabirds and caused significant outbreaks in marine mammals, leading to the tragic deaths of 20,000 South American sea lions.

Impact on Wildlife Populations

The consequences of HPAI in the Antarctic region are potentially devastating. Avian influenza, particularly strains H5 and H7, primarily affects birds but can also spread to mammals through predators and scavengers feeding on infected birds. In this case, marine mammals, including fur seals, sea lions, southern elephant seals, and dolphins, are at risk. Among birds, gulls, skuas, hawks, caracaras, terns, and shorebirds are particularly vulnerable. The presence of the virus in the Antarctic region poses a significant threat to the delicate balance of its ecosystems, potentially leading to a decline in breeding populations of various avian and marine species.

Scientific Response and Monitoring Efforts

In response to this crisis, the BAS, in collaboration with the Government of South Georgia & the South Sandwich Islands (GSGSSI), has initiated comprehensive monitoring and management efforts. These include enhanced biosecurity measures and a tiered response plan to track the outbreak's progression and mitigate its impact. Vigilance remains paramount as scientists continue their research and closely monitor avian and marine populations in the affected regions.

Concerns for Remote Populations

One of the most significant concerns arising from this outbreak is the potential impact on remote populations of penguins and seals. These animals, already facing challenges due to climate change and other environmental factors, are now threatened by the presence of HPAI. Remote islands between the southern tip of South America and the Antarctic Peninsula, including the Falkland Islands, are identified as high-risk areas due to the presence of various vulnerable wildlife groups. As these islands provide crucial habitats for numerous species, the introduction of avian influenza could disrupt entire ecosystems.

Potential for Pandemic Outbreaks: Focus on H5N1

The H5N1 strain of avian influenza poses a significant threat to public health due to its potential to trigger a widespread influenza pandemic. A pandemic occurs when a new influenza virus emerges, capable of sustained human-to-human transmission, especially when the human population lacks immunity against it.

According to the World Health Organization (WHO), from January 2003 to November 2022, there have been 868 documented cases of H5N1 infection in humans, leading to 457 fatalities. Importantly, as of now, there is no evidence of bird flu spreading from human to human. The prospect of currently-circulating avian, swine, and other zoonotic influenza viruses causing a future pandemic remains uncertain. Vigilance and research are crucial in understanding and mitigating this potential threat.

• Avian Influenza Concerns in India India faces specific challenges concerning avian influenza:
• Lack of Active Surveillance: Active monitoring for avian influenza is insufficient, raising concerns about the timely detection and containment of outbreaks.
• Unvaccinated Poultry Birds:Unlike some regions, Indian poultry birds are not routinely vaccinated against flu, potentially leaving them vulnerable to the virus.
• Risk Factors Amplifying Virulence:Farms with diverse animal populations or those situated near wetlands create environments conducive to the development of more virulent strains. These strains could potentially cross over to humans, heightening the risk of widespread infections.

Conclusion

The detection of Highly Pathogenic Avian Influenza in the Antarctic region serves as a stark reminder of the interconnectedness of global ecosystems. As human activities continue to impact the environment, wildlife in even the most remote areas is not immune to emerging threats. Addressing the challenges posed by HPAI in Antarctica requires swift and decisive action, including international cooperation, rigorous research, and effective management strategies. Only through such concerted efforts can we hope to mitigate the impact of this outbreak and safeguard the delicate balance of the Antarctic ecosystem for future generations.

Source - DTE