On March 18th Robert F. Kennedy Jnr. Secretary of the Department of Health and Human Services (HHS), opined that outbreaks of highly pathogenic avian influenza should be allowed to run their course without federal or state intervention. This misinformation generated by Secretary Kennedy in his Fox News interview was immediately endorsed by Brook Rollins, Secretary of the Department of Agriculture, charged with the responsibility to prevent and control livestock and poultry diseases.
The statement by Secretary Kennedy evoked a negative response from Congress and general opprobrium from epidemiologists, virologists and practicing poultry veterinarians. A rebuttal was published in early July in Science* authored by epidemiologists and infectious disease specialists affiliated with the Bloomberg School of Public Health, Johns Hopkins University.
The implication in the Kennedy statement was that any survivors, possibly less than five percent of the flock, would be resistant to avian influenza and might be suitable to propagate ‘resistant chickens.’ Breeding from survivors would be impractical given that commercial laying strain hens and turkeys are hybrids and any attempt at propagation would result in profound loss of commercial traits. Those following Secretary Kennedy’s proposal may be left with a few chickens or turkeys at the end of an outbreak, but their progeny would be grossly inferior to commercial product. In any event the likelihood that they would be refractory to HPAI is remote. Chicken strains producing either eggs or meat represent the genetic contribution of at least three generations of highly selected male and female lines. The proposed program analogous to ‘genetic suicide’ would revert the U.S. poultry to the early 1900s and place the industry at an extreme disadvantage. Failure to effectively suppress HPAI will inevitably create shortages, benefiting potential exporters to the U.S. and result in higher prices to consumers.
The second consequence of the Kennedy “Let er’ rip” approach would be widespread dissemination of virus from affected farms. The companion article in this edition makes reference to the 2020 and 2021 outbreaks of H5N8 HPAI in commercial waterfowl in France. It was determined that the period between infection initiating propagation of virus and an eventual diagnosis extended to nine days. The USDA-APHIS in cooperation with state regulators and industry veterinarians has refined and expedited preliminary and confirmatory procedures for diagnosis, followed by depopulation of flocks to limit spread. This has limited outbreaks as evidenced by field investigations suggesting that in early 2025 seventy percent of outbreaks were associated with direct or indirect introduction of virus from wild bird reservoirs and were less associated with farm-to-farm transmission. Allowing perpetuation of infection on large complexes some of which exceed two million laying hens would inevitably result in infection of neighboring farms in addition to free-living mammals and non-migratory resident birds. This has occurred following infection of dairy herds with bovine influenza attributed to the H5N1 B13.3 strain.
Willful failure to control avian influenza would result in universal embargos on U.S. exports of broiler, turkey and egg products. Compliance with WOAH standards require rapid control of outbreaks through quarantine, depopulation and appropriate structured surveillance. The risk of losing export markets is the major justification of opposition to vaccination. This modality as an adjunct to biosecurity has been proposed for egg-production and turkey flocks in high-risk areas geographically removed from the main centers of broiler production. The policy suggest by Secretary Kennedy with initial concurrence by Secretary Rollins, is a negation of all that USDA has achieved over decades and ignores progress exemplified by the National Poultry Improvement Plan and establishment of WOAH compartments free of infection. The Kennedy approach would destroy the confidence established in the APHIS by veterinary regulators in importing nations.
The Science article did not adequately stress the consequences of even the remote possibility of emergence of a zoonotic strain of H5N1. It is axiomatic that the quantum of virus circulating among infected flocks will predicate mutations or even facilitate a recombinant event that may establish H5N1 as a human pathogen. Although the World Health Organization and USDA regard the emergence of a strain capable of human-to-human transmission as remote, the consequences would be catastrophic. Any future conformation of sustained transmission from cattle or poultry to humans would be regarded with concern by consumers, potentially depressing the sale of eggs and poultry meat. To date humans diagnosed with mild symptoms of H5N1 as a result of intimate contact with infected flocks or herds have represented end-hosts with no contagion among their contacts.
The economic and social impacts of the COVID pandemic extending from 2020 through to effective immunization, suggest the magnitude and consequences of emergence of a zoonotic strain of H5N1. This is especially relevant with the prevailing reluctance to promote human vaccination. The achievements of “Operation Warp Speed” appear to have been negated through cancellation of research on mRNA vaccines by Secretary Kennedy. This is attributed to the embrace of pseudo-science, sophistry and misinformation in HHS agencies, driving public health policy. In the absence of a fully staffed CDC with appropriate funding and resources, including outreach to state and regional departments of health, the emergence of an H5N1 outbreak among humans would be delayed to the detriment of control measures. Distrust of public health and rejection of masking and quarantines would promote dissemination of infection. Irrespective of species, control of avian influenza in poultry should be based on current control measures supported by localized tactical vaccination.
To paraphrase Dr. Mandy Cohen, previously Director of the CDC and the North Carolina Department of Health, facts and science must determine policy, independent of politics. Secretary Kennedy is entitled to his opinions but not his facts or established scientific principles.
To review previous postings on HPAI and the risks of emergence of a zoonotic strain enter "avian influenza" in the SEARCH button
Sorrell, E. et al. The consequences of letting avian influenza run rampant in US poultry. Science July 3, 27-29