Updated guidance on the Highly Pathogenic Avian Influenza - Environmental update for USAP personnel


Summary

There is a high risk that Highly Pathogenic Avian Influenza (HPAI H5N1) will arrive in the Southern Ocean during the 2023/24 austral summer.  Current outbreaks of this disease have resulted in the deaths of hundreds of thousands of seabirds around the world. The introduction of this virus into the Southern Ocean may result in high mortality among affected seabird and marine mammal populations in Antarctica. There is a heightened risk of HPAI introduction or spread by infected migrating seabirds, as well as by contaminated boots, clothing, and equipment from humans. In response, the USAP is requiring enhanced biosecurity protocols in the Antarctic this season, including pre-landing surveillance, decontamination of boots and gear between seabird colonies, reporting of suspected HPAI outbreaks to NSF OPP Environmental (OPP-ENV@nsf.gov), and enhanced management of areas impacted by HPAI.

Background on HPAI

HPAI (commonly called “avian flu”) is a highly contagious, viral disease that causes high rates of mortality in poultry and wild birds. New strains of HPAI are generally spread rapidly along wild bird migratory pathways. As of June 2022, an outbreak of Eurasian H5 HPAI was detected in the northern hemisphere. The outbreak has been reported throughout the US and across the globe in a wide variety of species including gannets, geese, terns, gulls, skuas, ducks, eagles, puffins, and penguins resulting in high levels of mortality. As of August 2023, HPAI outbreaks have been detected in Chile, including in the area surrounding Punta Arenas, and has been detected in seabirds and marine mammals.

The transmissibility of avian flu varies. In wild birds, it is transmitted via the fecal-oral route and through environmental contamination (mostly water). Direct contact and as well as respiratory droplets are both likely additional routes of transmission. The close proximity of colonial nesting seabirds leads to a greater risk of disease spread. For more information about HPAI in wild birds, please see the FAQs provided by the Interagency Steering Committee for Surveillance for Highly Pathogenic Avian Influenza in Wild Birds, and the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS) detections of HPAI in wild birds.

This virus affects mammals as well as birds. Since June 2022, HPAI has caused high levels of mortality in harbor and grey seals (as well as other terrestrial and marine mammals) in the US and Canada. In Chile, mortalities of more than 3,300 sea lions and over 900 Humboldt penguins have been reported.

Migratory bird species arriving to the Southern Ocean (mostly between September and November) could transmit HPAI to the region, coinciding with the arrival of penguins and other breeding seabirds.

Seabird, and wildlife disease experts, including through the Council of Managers of National Antarctic Programs (COMNAP) have released guidance for surveillance, monitoring, and response for HPAI outbreaks that might occur this season. This guidance is based on input from Avian Influenza experts, as well as experts in Antarctic wildlife health, including from the Scientific Committee for Antarctic Research (SCAR).

Risks to Public Health

Previously, there have been 868 human cases of HPAI H5N1 with 457 deaths since 2003. Only seven human cases of the current HPAI H5N1 virus have been reported since 2021. This translates to a low risk of infection in humans. 

The current circulating lineage of this virus (lineage 2.3.4.4) has been reported in humans in China, Laos, Russia, Nigeria, the UK, and the U.S., with no examples of human-to-human transmission detected thus far. To date, all human infections with HPAI have been in people closely interacting directly with birds.

Risks to Antarctic Wildlife

HPAI results in rapid and high mortality (as much as 100%) in infected wildlife groups. It is possible that the virus could survive in the environment beyond the austral summer. HPAI Symptoms in birds include loss of balance, trembling, lethargy, swelling of the head, hemorrhaging, and respiratory distress. HPAI symptoms in marine mammals include respiratory issues, neurological issues, tremors, and paralysis.

Field Guidance for all USAP Participants

  • Do not visit seabird colonies or come into contact with concentrations of birds in the Gateway City prior to departing for Antarctica. Particularly, do not visit the Magellanic penguin colonies close to Punta Arenas, Chile
  • Before entering a wildlife colony, conduct a pre-landing/pre-entry surveillance with binoculars from a distance of 150m to identify unusual behavior. Common behavioral signs of HPAI include:
    • Unusual mortality
    • Neurological issues (loss of coordination and balance)
    • Trembling head and body
    • Lethargy and depression (lying down, unresponsiveness, drooping wings)
    • Swollen head
    • Twisting of the head and neck
    • Hemorrhages on legs and under the skin of the neck
    • Respiratory distress (open mouth/gaping, coughing, sneezing, gurgling)
    • Closed and excessively watery eyes
  • If signs of HPAI are detected, do not enter the colony. Note information such as the date/time/location, HPAI signs detected, approximate number and species of birds affected, and photographs and videos as possible. Report this information as soon as possible to the Station Manager or the research vessel’s MPC, and to NSF OPP Environmental (OPP-ENV@nsf.gov)
  • Maintain at least 5 m distance from seabirds unless permitted to approach closer
  • Do not handle dead or sick birds unless you are specifically permitted to do so and have received clearance from NSF OPP Environmental
  • Boots and equipment should be decontaminated before and after any colony visit. This includes decontamination between colony visits if visiting multiple colonies in the same day
  • All boots, exterior clothing, and equipment should be decontaminated with a broad spectrum disinfectant such as 70% ethanol, Virkon S, F10, soap + 10% bleach solution, or 0.1% iodine solution
  • Refrain from sitting or lying on the ground around wildlife
  • USAP personnel specifically authorized to handle sick or dead birds should assume that HPAI will arrive in Antarctica and wear appropriate Personal Protective Equipment (PPE) during handling including gloves, N95 respirator or mask, and eye protection
  • Samples from dead or potentially infected animals should only be taken by persons who 1) have been trained to do so, (2) are wearing appropriate PPE and taking appropriate biosecurity precautions, (3) have a clear need and permission from NSF OPP Environmental to do so in light of an outbreak, and (4) have permits to collect diseased samples
  • Potentially HPAI positive sample (including cloacal and pharyngeal swabs) tubes should be individually labeled. The outside of the sample container should be disinfected, clearly marked as samples for HPAI analysis, and stored separately from other samples. Samples should never be stored in areas containing food
  • Ensure proper labeling in adherence to the testing laboratory requirements and/or federal regulation, if shipping. Labeling should identify sample contents, date collected, and responsible contact person
  • PPE and other material used in the collection of samples should be combined in a sealable bag and disposed of in sanitary waste. Any PPE used in the collection of presumed HPAI-positive samples should be combined in a sealable bag, 20ml of broad spectrum disinfectant should be added before disposal in hazardous waste. Hands should be washed with soap or sanitized with alcohol-based hand sanitizer after any bird-handling

Additional Resources

Questions? Write to OPP Environmental at OPP-ENV@nsf.gov.