Dr. David A. Kessler warned of the need to effectively control avian influenza before mutations allow the virus to become zoonotic on an extensive scale or even to become contagious. Writing in the New York Times, Kessler noted the failure of APHIS to control HPAI in poultry flocks, the alarming incidence rate in dairy herds and emergence of seasonal avian influenza in migratory marine birds and waterfowl in Asia, Africa, Australasia and Europe.
Dr. Kessler has earned impressive credentials both a physician and lawyer. He was the Commissioner of the Food and Drug Administration during the George H. W. Bush and Clinton Administrations and was scientific advisor to the Biden Administration during COVID 19. He has served as the Dean of medical schools at Yale and the University of California, San Francisco where he now serves as a professor.
To date there have been less than 60 cases of H5N1 in humans, contracted from exposure to infected poultry flocks during depopulation and among workers on dairy farms exposed to contaminated milk.
Extension of H5N1 from poultry to humans was first documented in 1997 in Hong Kong resulting in 18 infections with six fatalities. Extensive endemic H5N1 infection in Asia commenced in 2003 with seasonal outbreaks in poultry flocks on five continents since this time with serious epornitics in the U.S. in 2015 and ongoing from 2022.
Dr. Kessler warned of consumption of non-pasteurized milk and the need for structured surveillance of dairy herds. This is in effect in California and Colorado and is soon to be implemented in Pennsylvania. Detection of infection in dairy herds should obviously be followed by quarantine including an embargo on movement of all animals from an affected herd for the duration of viral shedding. It is axiomatic that necessary PPE should be supplied and correctly used to prevent human infection, Although symptoms of infection in exposed workers are mild, contracting H5N1 adapted to mammals may result in recombinant events or viral mutation to become more pathogenic in humans.
The list of APHIS-confirmed outbreaks of avian influenza in egg production, turkey and broiler flocks during November attest to the inadequacy of a “stamping-out” program based on the false premise that HPAI is an exotic disease. The rapidly increasing incidence rate among flocks in three of the North American flyways denotes that the infection is both seasonally and regionally endemic, disseminated by migratory birds and possibly now resident species. Ongoing cases of avian influenza among large populations of domestic poultry and dairy cattle will create the potential for mutations. This reality is characterized by Dr. Kessler as “increasing the risk that the virus mutates and evolves to allow human-to-human transmission that will be hard to stop.”
According to Dr. Kessler there is an indication from isolates obtained from human cases in Washington State that the effectiveness of oseltamivir as an antiviral therapy has declined together with demonstration of a specific mutation in a California isolate that would reduce the effectiveness of paloxavir. At this time, the U.S. would be reliant on current antivirals and supportive therapy for patients. A stockpile of 5 million doses of H5N1 vaccine approved for humans is available with the possibility of an additional 5 million. The E.U. has imported H5N1 vaccine from the U.S., now deployed for workers in poultry and fur-farms in Finland as a precautionary measure.
Dr. Andrew Pekosz of the Department of Molecular Microbiology and Immunology at Johns Hopkins Bloomberg School of Public Health noted, “If we start to detect people with H5N1 with contact only with another person infected with H5N1, that will be a real danger sign.” This would indicate contagion and raise the potential of a 1918 outbreak or even a less extreme version of the 2009 H1N1 ‘swine flu’ pandemic that claimed 250,000 lives worldwide.
Dr. Pekosz did however comment, “The good news is so far, no clear person-to-person transmission of any significant nature has been documented or detected. This may only be a matter of time.”
The U.S. and world human populations would be best served by a change in APHIS policy allowing administration of available vaccines for egg production, breeder and turkey flocks in high-risk areas. Avian influenza is more than a bird problem. At present it is a potential human problem transcending the narrow issues of restriction on export of broiler parts.
Previous articles on this topic posted on EGG-NEWS can be retrieved by entering ‘avian influenza’ and ‘HPAI’ in the SEARCH block).