Avian influenza, also known as avian influenza, is caused by influenza A virus and mainly infects birds, including poultry and poultry. Avian influenza can infect an entire flock within days and is spread through respiratory secretions, feces and saliva.
Transmission can occur directly or through contaminated food and water. especially, Avian influenza viruses are extremely resistant and can survive for a long time, even at low temperatures. According to pathogenicity criteria, avian influenza strains are divided into highly pathogenic and low pathogenic. Highly pathogenic avian influenza (HPAI) is a highly contagious variant of avian influenza primarily associated with influenza A virus H5N1 and H7N9 strains. H5N1 is the most widespread of the HPAI strains and was first isolated in 1996 from farmed geese. in China.
The world is experiencing the largest bird flu epidemic on record, which is affecting poultry and wild bird populations. The epidemic, which is the largest recorded in Europe, North America and Japan, is primarily driven by the H5N1 avian influenza virus clade 2.3.4.4b. HPAI infections caused by H5N1 clade 2.3.4.4b viruses in 2022 131 million poultry lost in 67 countries. The disease spread rapidly in 2023, with 14 additional countries reporting infections.
In addition, the World Organization for Animal Health (WOAH) reported that in the four weeks from May 5 to June 1, 2023, 82 and 198 outbreaks were reported in poultry and non-poultry, with more than 860,000 deaths in poultry people. The current outbreak of highly pathogenic avian influenza is affecting more wild birds than ever before, with the World Health Organization (WHO) estimating that there may be nearly 42 million since the epidemic was recorded originating in the Netherlands in October 2021 Only poultry and wild birds are infected.
Actually, Highly pathogenic avian influenza (HPAI) has become a pandemic of global concern Some countries, including the UK, the US and Japan, have suffered catastrophic losses in poultry. The World Health Organization estimates that at least 60 countries may be affected by the HPAI pandemic.
A team of researchers from Peru reviews the current status of avian influenza, assesses the disease’s impact on humans, and asks whether “We are prepared for another possible pandemic“.
Increased infectivity in mammals
It is thought that high infection rates among wild birds may have contributed to the rapid spread of highly pathogenic avian influenza across continents, from Europe and Asia to North America.The author explains that it should be noted that Wild migratory birds, especially waterfowl, are natural vectors Avian influenza viruses (hosts and reservoirs).The high prevalence and long incubation period of avian influenza viruses in the respiratory tract and intestines of these birds may result in Transmission is greater over long distanceseven between continents, along migration routes.
It is understood that highly pathogenic avian influenza mainly occurs in birds; however, in rare cases, May cause infection in other animals, including humans.according to Gregory Torresa member of WOAH, is Avian influenza viruses are more likely to transform into more pathogenic and contagious forms.
Even more worryingly, it can also lead to increased infectivity and pathogenicity in mammals.In fact, the Director-General of the World Health Organization Tedros, Recent warnings of possible outbreaks of avian influenza in humans.
first batch of cases Infection among mammals Confirmed by H5N1 Spanish mink farms in October 2022. This outbreak is alarming for two reasons: the first is that avian influenza viruses have adapted to be pathogenic in mammals, and the second is that minks are closely related to domestic ferrets. Since then, many reputable institutions have reported the spread of avian influenza infections in many mammals.Recently, the spread of H1N5 strains (clade 2.3.4.4b) in marine mammal species has been confirmed
Likewise, the author considers the recent “worrying” Domestic cats infected with avian influenza H5N1 (clade 2.3.4.4b) has been reported in Poland Vet Diary. Recent findings about the spread of avian influenza among mammals “do not bode well.”
disturbing trend
Human infections are caused by Bird flu virus may follow airborne transmission pattern, Similar to SARS-CoV-2/COVID-19. They believe that prolonged and unprotected interactions with domestic birds are the main reason for the increased likelihood of human infection with avian influenza. In this case, flu-like symptoms can range from mild or no noticeable changes to severe changes and even death.
The authors noted that the first documented human cases of influenza A (H5N1) infection were reported in Hong Kong in 1997 and traced to domestic and wild waterfowl in Guangdong, China. Although the number of human cases of avian influenza in this outbreak was limited to 18, the infection resulted in 6 deaths, including 1 fatality. The mortality rate is as high as 33%, which is depressing. Since then, there have been sporadic reports of human infections with avian influenza.The World Health Organization reports that there have been More than 890 human cases of H5N1 infection in 22 countries Since November 2003, the mortality rate has soared to an alarming 53%. However, the data also suggests that H5N1 is still too weakly contagious in humans to trigger a larger outbreak, “possibly because of the rarity of human-to-human transmission.”
It was found that almost all H5N1 influenza human cases exposed to infected poultry.Currently “there is no evidence that the virus can be transmitted from newly infected mammals to humans.” Therefore, the public health risk Avian influenza epidemic remains at low levelbut the fact that it spread from birds to mammals and then between them “suggests disturbing trend“.
The number of wild mammals infected with highly pathogenic avian influenza-like diseases is increasing in many countries. Global concerns are growing that the situation is quite serious and that it could become a new pandemic.
agree with this Ursula HoferResearcher at China Shipbuilding Industry Corporation IREC (Research Institute for Hunting Resources), he recently explained in an exclusive statement to this media that avian influenza “For scientists, he was a pandemic candidate, but COVID-19 defeated him”.
The spread of avian influenza viruses from birds to mammals increases the risk of their spread to humans. They believe the situation could become catastrophic, If the virus mutates into a variant with greater infectivity and human transmissibility.
‘The world is not ready for another outbreak’
Despite ‘we haven’t fully recovered’ from the Covid-19 pandemic, The world is not ready for another outbreak“. Therefore, the researchers commented, “There is a need to urgently initiate measures to respond to the highly pathogenic avian influenza pandemic through various directives from governments and intergovernmental organizations. ” According to WOAH guidance, the first line of defense against avian influenza is early detection of disease outbreaks. Accurate early warning system “It can help provide an effective and timely response to prevent and control the spread of the epidemic in relevant geographical areas and near and far.”
Likewise, they noted the need to develop a One Health strategic framework among entities such as the World Health Organization and WHO to contain and prevent the epidemic. Biosecurity measures against highly contagious and pathogenic diseases “may never be perfect, as we have discovered during the COVID-19 pandemic; however, these precautions must be designed and implemented.”
In conclusion, given the risk that the pandemic may affect human life, “we must remain vigilant and ensure that all preventive and precautionary measures are implemented to ensure Spread of avian influenza in mammals curbed“.
Public education ‘must also be considered from the beginning’ Counter misinformation through social media, from the scientific community to the public. “The more the virus spreads among mammals, the greater the risk of developing new variants adapted for human transmission. As with the COVID-19 pandemic, “this may result in new variants that are more pathogenic, transmissible, and virulent to humans.” An updated variant of force. “