#17,303
Although the current threat to human health remains low, the recent spillover of avian H5N1 into both terrestrial and marine mammals (see SERNANP Reports At Least 585 Sea Lions killed by Avian Flu) - and worrisome signs suggestive of mammal-to-mammal transmission - have inspired a flurry of avian flu guidance documents to be released by public health agencies around the globe.A week ago, in BCMJ - Avian influenza: A BC Clinician’s Guide to Diagnosis and Management, we looked at guidance from the British Colombian government. Yesterday the Public Health Agency of Canada (PHAC) released updated guidelines for both Healthcare professionals and prevention advice for the general public.
Due to their length, I'll only post the links and a few excepts. Follow the links to read them in their entirety. I'll have a brief caveat after the break.
Avian influenza A(H5N1): For health professionals
What health professionals need to know about avian influenza A(H5N1)
Outbreaks of avian influenza A(H5N1) in domestic and wild birds and some wild mammals have recently emerged and become widespread in Europe and North, Central and South America, including across Canada. Government authorities in Canada are currently responding to the outbreak of influenza A(H5N1) in farmed birds and wildlife across Canada.
Influenza A(H5N1) is a subtype of avian influenza virus that mainly infects birds, but causes rare and sporadic human cases.
Human cases of influenza A(H5N1) have primarily occurred due to zoonotic transmission through direct contact with infected birds (dead or alive) or contaminated environments. Human-to-human transmission is extremely rare.
Clinical illness caused by influenza A(H5N1) is predominately observed in children and young adults. The virus mainly affects the respiratory tract but can also cause gastrointestinal or central nervous system manifestations. Infection may progress to severe illness and can be fatal.
Clinicians and front-line laboratory personnel are encouraged to follow the Protocol for Microbiological Investigations of Severe Acute Respiratory Infections (SARI) to facilitate the diagnosis of severe respiratory infection caused by pathogens with epidemic potential.
Antivirals used to treat influenza can be effective in reducing morbidity and mortality, especially if administered early in the course of illness. Prophylactic use of influenza-specific antivirals (pre and post exposure) may prevent illness. Seasonal influenza vaccines do not offer protection against influenza A(H5N1).
Human infections of influenza A(H5N1) are notifiable under the International Health Regulations (2005). Provincial and Territorial public health authorities are required to report confirmed and probable human cases of influenza A(H5N1), irrespective of illness symptoms or severity, to the Public Health Agency of Canada (PHAC) within 24 hours of their own notification, as per the Emerging Respiratory Pathogens and Severe Acute Respiratory Infection (SARI) case report form. PHAC is required to report any human case detected in Canada to the World Health Organization according to the International Health Regulations (2005) requirements and timelines.
For detailed recommendations on public health management and reporting requirements, consult the appropriate local, provincial, or territorial health authorities.
Avian influenza A(H5N1): Prevention and risks
(SNIP)
Preventing avian influenza A(H5N1) infections
Minimizing contact with secretions (mucus, saliva), blood, or feces from infected birds and mammals is key to preventing avian influenza A(H5N1) infections.
The risk of infection is low for the general public, however basic precautions are always recommended to prevent transmission of zoonotic diseases (diseases that transmit from animals to people), including avian influenza:
People who have close contact with poultry, wild birds, or other wildlife that are suspected or confirmed to be infected with avian influenza A(H5N1) should take additional precautions during handling or when working in heavily contaminated environments:
- Keep a distance from wild birds and other wild animals, and don't touch, feed, or handle them
- If contact is unavoidable, wear gloves or use a doubled plastic bag and avoid contact with blood, body fluids and feces. Remove gloves if worn, and wash your hands thoroughly with soap and water. If soap and water aren't available, use a hand sanitizer containing at least 60% alcohol
- Always wash your hands after being in an area where birds and other wildlife are living or nesting, such as in parks or zoosChildren should be monitored to ensure proper handwashing
- Pets should be kept away from birds and wildlife and their feces
There is no evidence to suggest that fully cooked wild game meat, organs or wild bird eggs are a source of avian influenza infection for people. However, because exposure to avian influenza can occur when handling wild birds and some wild mammals, it is recommended that hunters and trappers take precautions when de-feathering, cleaning and preparing wild game, along with following other safe food handling procedures.
- Wear masks and eye protection to protect your eyes, nose and mouth from contaminated dust, feathers, secretions and feces
- Wear other protective clothing, such as gloves, boots and coveralls
- Prior to cleaning up contaminated areas, mist dry areas with low pressure water to prevent fecal matter, dust and feathers from being stirred up into the air
- Change clothing and footwear, and wash hands thoroughly with soap and water before moving onto other activities
- Follow any additional occupational health guidelines, as directed by your occupational health provider
Thoroughly cooking meat, organs and eggs harvested from wildlife will kill the avian influenza virus and other potential pathogens, such as Salmonella.
The annual seasonal influenza vaccine ("flu shot") does not provide protection against avian influenza. However, if you are involved in the food production system or agricultural settings, getting a seasonal flu shot each year can help reduce the spread of human influenza viruses between people and between people and animals.
It is worth mentioning that while fully cooked wild game, poultry, or eggs are considered safe for consumption, we have seen a few instances where people - mostly in Asia - appear to have been infected from consumption of under-cooked poultry, or during the preparation of poultry for cooking.
While exposure to frozen or chilled meat has only rarely been linked to HPAI H5 infection, in 2017's Appl Environ Microbiol: Survival of HPAI H5N1 In Infected Poultry Tissues, we looked at several studies on the long-term viability of HPAI H5N1. They found:
The maximum period for viral survival was observed in samples stored at +4°C in all tissue types, i.e., 240 days in feather tissues, 160 days in muscle, and 20 days in liver.
Suffice to say, the safe food handling advice proffered above should be taken seriously.
