by Karla Ciaglo
Dr. Paulo H. Verardi, a virologist and head of the Department of Pathobiology and Veterinary Science at the University of Connecticut, is closely monitoring the ongoing H5N1 bird flu outbreak here and its potential public health implications.
Dr. Paulo H. Verardi is the head of the Department of Pathobiology and Veterinary Science at the University of Connecticut, with a focus on virology and vaccinology. Credit: Contributed / University of Connecticut, College of Agriculture, Health and Natural Resources
As the virus spreads to dairy cattle, Verardi provides critical insight into its characteristics, transmission risks, and response efforts. He notes that the current response level is at DEFCON 4, meaning that officials and experts are in a state of awareness and preparedness. At this stage, efforts are focused on gathering information and strengthening response capabilities rather than taking immediate emergency action.
Bird flu is caused by several influenza viruses, including H5N1 Highly Pathogenic Avian Influenza (HPAI). Verardi explains that two specific genotypes, D1.1 and B3.13, are subjects of ongoing monitoring. D1.1 has been detected in wild and domestic birds, including in Connecticut, while B3.13 has been associated with an outbreak in dairy cows in the United States. B3.13 has shown adaptation to mammals, including cats, which may represent a step toward human transmission.
Verardi explains that mutations play a key role in how bird flu viruses adapt to different hosts. Influenza viruses constantly change, helping them evade immunity and potentially spread more effectively. Humans currently have no prior immunity to H5N1, and frequent interactions between the virus and mammals increase the chances of further adaptation.
H5N1 has already infected mammals and caused severe disease in humans, but efficient human-to-human transmission would require additional genetic changes through mutations or reassortment. Greater contact between the virus and mammals raises the likelihood of such changes occurring.
Bird flu viruses typically bind to bird cell receptors, making them well-suited for replication in birds. For human infection to occur, specific genetic changes would be necessary. While the current risk of human transmission in Connecticut is low, Verardi warns that new variants could emerge, altering this assessment.
Yale professor, Dr.Howard Forman, a specialist in radiology, health policy, and healthcare management describes H5N1 as an unpredictable virus, stating, “H5N1 has always been a bit of a black box. We sort of know it will eventually be a human problem. We don’t know how bad or when. And we are ill-equipped to slow the path to that day when it does.” He adds, “Now, with more limited access to centralized federal data or a federal response that meets the moment, [it is] probably more concerning.” However, Forman clarifies that while the virus has reappeared in previously infected herds and some human cases have shown mutations suggesting a step toward human-to-human transmission, “alone this is not, itself, frightening. Just more info.”
The Connecticut Department of Energy and Environmental Protection has reported numerous detections of H5N1 in wild birds across the state, particularly affecting waterfowl.
State officials have confirmed that bird flu is killing geese in Connecticut, following reports of dozens of dead birds at Hanover Pond in Meriden. Residents expressed concern over the outbreak, as the area is home to diverse bird species. Experts warn that bird flu spreads easily among wild birds and can be difficult to control. While the virus is not easily transmitted to humans, health officials advise avoiding contact with dead birds. Connecticut has also seen cases in backyard poultry flocks, raising concerns about potential economic impacts, including rising egg prices due to supply shortages.
Residents are encouraged to report findings of multiple dead birds in the same area to DEEP’s wild bird mortality database, though individual cases may not receive direct response due to resource constraints. Verardi explains that winter conditions, such as frozen water sources, may have played a role in concentrating birds into smaller areas, facilitating the spread of the virus.
Vaccines for bird flu exist, but Verardi notes that their use in the U.S. is limited due to considerations such as cost, effectiveness against evolving strains, and trade restrictions. The current approach in the U.S. relies on biosecurity measures, surveillance, and culling of infected flocks.
Regarding human vaccines, Verardi highlights the challenges posed by the rapid mutation rate of influenza viruses. Traditional flu vaccines require months to produce, while newer mRNA vaccines, though available, present cost and storage considerations. Pharmaceutical companies, including Moderna and Pfizer, have initiated efforts to develop H5N1 vaccines, and emergency response measures could be utilized to accelerate vaccine deployment if needed.
He offers that recombinant viral vector technology is another potential approach that may provide stronger and longer-lasting immunity.Recombinant viral vector technology uses a harmless virus to deliver genetic instructions that help the body build immunity against a disease. This method has been used in vaccines for Ebola and COVID-19. Verardi explains that while it could provide longer-lasting protection, traditional and mRNA vaccines would still be the main options in a bird flu outbreak.
Verardi pointed to the The 2009 H1N1 outbreak and says that it serves as an example of how vaccines can be developed and distributed within months.He notes that scaling up vaccine production presents challenges, including cost, regulatory approval, and manufacturing capacity.
Traditional egg-based vaccines depend on chicken eggs, which may become scarce during an outbreak, while mRNA vaccines require specialized storage conditions.
Surveillance and early detection are central to preventing outbreaks. Verardi explains that researchers track bird flu mutations through genetic sequencing and global surveillance efforts. While the current risk level in Connecticut is low, continued monitoring remains essential.
Environmental factors, such as climate change and deforestation, can influence the spread of bird flu by affecting bird migration patterns. High-density animal farming may also contribute to disease transmission. Verardi notes that pigs can serve as “mixing vessels” for influenza viruses due to their ability to be infected by multiple strains simultaneously. Other mammals, such as cats and dogs, could also participate in viral transmission, though pigs are considered more efficient in this process.
Outbreaks and pandemics require specific conditions to align. Verardi emphasizes that high-density animal farming and other factors may contribute to disease spread, underscoring the role of surveillance and biosecurity in mitigating risks. Connecticut’s preparedness efforts include maintaining surveillance programs and ensuring readiness to respond to potential outbreaks..
As of Feb. 2025, bird flu has been detected in over 11,600 wild birds, affecting both migratory and local populations. The virus has also impacted the poultry industry, with more than 156 million poultry affected in outbreaks spanning 51 jurisdictions. Additionally, bird flu has spread to dairy cattle, with 959 infected herds reported across 16 states.
A new H5N1 bird flu variant, D1.1, has been detected in Nevada dairy cattle, raising concerns about its spread and potential impact on human health. Scientists worry that existing immunity and vaccines may not be effective against this strain, which has already been linked to severe human cases, including a fatality in Louisiana.
Meanwhile, according to reports, limited testing and a lack of timely updates from federal agencies are hindering efforts to track the outbreak. With rising poultry infections and gaps in farm biosecurity, experts stress the need for better data sharing to monitor the virus’s evolution and potential risks.
Past infectious disease events, including COVID-19, demonstrate the need for preparedness and proactive measures. While the future course of bird flu remains uncertain, continued monitoring and research are necessary to understand and respond to the evolving situation.
Residents of Connecticut are advised to avoid handling dead birds due to potential health risks. DEEP provides specific disposal recommendations for those who must remove a bird from a pathway or backyard. These include using gloves or a shovel to double-bag the bird, disinfecting the area with a bleach solution, and thoroughly washing hands afterward Bird flu symptoms in humans range from mild, such as red eyes or mild respiratory issues, to severe flu-like symptoms, including fever, cough, fatigue, and muscle aches. In some cases, it can lead to pneumonia, brain inflammation, or diarrhea. Symptoms typically appear within 1 to 10 days after exposure.
Discover more from InnerCity News
Subscribe to get the latest posts sent to your email.
