H5N1 in Cats: A Closer Look at What We Know and Don’t Know
In recent weeks, media coverage about H5N1 avian influenza in cats has created significant concern among pet owners and led to rapid policy changes across the pet food industry. While concern about pet health is always warranted, it’s crucial to examine the evidence carefully and understand what questions remain unanswered. As a store dedicated to evidence-based pet nutrition, we believe it’s important to look beyond headlines and examine the complete picture.
The Oregon Case: What Actually Happened
The recent surge in concern stems primarily from a single case: a cat in Oregon that died after reportedly consuming raw turkey pet food. While genomic testing found matching H5N1 viral DNA in both the cat and the food (Northwest Naturals raw turkey), this finding deserves closer scrutiny. The food in question had undergone High-Pressure Processing (HPP), a preservation method designed to eliminate pathogens. More importantly, the testing methodology used only identified viral DNA presence – it did not differentiate between live and killed virus.
This distinction is crucial. The presence of viral genetic material alone doesn’t necessarily indicate a causative relationship. Think of it like finding fragments of a broken key in a lock – while the pieces are there, we can’t automatically conclude they were responsible for opening (or in this case, damaging) the mechanism.
Further, at the time of writing we do not know anything about the health status and age of the cat. These are important details that could change how we view this from a scientific perspective. Furthermore, we are unclear if this particular product was the only food source for this cat. Was the cat also receiving raw milk, raw poultry from the grocery store, raw eggs? There is also social media evidence that this cat was not an indoor cat, and went outside and into public along with dogs from the same household [1]. This fact demonstrates the potential that the cat became infected from outside sources, or that the dogs in the household were potential carriers of the virus.
Updated Findings: Unopened Food Tested Negative
As of mid January we learned that unopened bags of Northwest Naturals product, from the same lot, did NOT test positive for H5N1 [1]. The Oregon Dept of Agriculture on January 7th confirmed that the only sample that tested positive was from the opened bag from the home of the cat who sadly passed [1]. Although they maintain that the food was the source of the infection, this evidence does not support that claim in my opinion. Instead, it likely means that the food was contaminated once opened, and not from the manufacturer. This information is supported by a total of 3 published studies, using a genetically similar surrogate virus (Avian influenza H7N7, H3N8), that demonstrate that HPP methodologies used in pet food manufacturing likely neutralize the virus [2,3,4].
In order to assess these types of situations appropriately I like to ask myself: “If the evidence as presented and conclusions made were submitted to a scientific journal for peer review, would those conclusions be accepted or rejected based on the evidence provided?” In this situation, the answer is no because the evidence does not provide enough evidence to support the conclusion. Instead, there are many more questions than answers. In this case, the only legitimate conclusions made are that the industry needs more research and more companies to step up to the plate to contribute to that research and raise the bar.
We want to be clear that we are not diminishing the severity of H5N1, we also think it is important to understand all the details before jumping to conclusions. A balanced and thorough analysis is the only way to mitigate future issues.
Historical Context Matters
Looking at the broader historical picture provides an important perspective. Over the past eight years, documented cases of H5N1 in cats have remained relatively rare given the global cat population and widespread consumption of raw poultry products. Let’s examine some key outbreaks:
– Netherlands (2020-2023): Among 1,654 cats tested, 87 were seropositive (5.3%), but we lack data on symptoms or mortality
– South Korea (2023): A shelter outbreak affected 38 of 40 cats, linked to raw pet food where proper sterilization protocols may have been compromised
– Poland (2023): Of 29 diagnosed cats, 20 showed symptoms and 11 died, with virus found in only one of five tested foods
– New York City (2016): 45 cats were diagnosed, but most showed minor symptoms and recovered, with only one reported death
These cases, while serious, suggest varying levels of severity and different transmission routes. The New York outbreak particularly challenges assumptions about uniformly severe outcomes.
The Testing Gap
A significant oversight in current discussions is the lack of comprehensive testing across different pet food categories. While raw food is under scrutiny, we have virtually no data about potential viral presence in kibble or canned foods. The assumption that high-temperature processing eliminates the virus, while logical and likely, remains untested in pet food manufacturing conditions.
Moreover, the extreme sensitivity of genomic testing – capable of detecting as few as 10 copies of genetic material – raises questions about the clinical significance of positive results. Are we finding concerning levels of active virus, or merely traces of degraded viral material?
Processing Methods and Safety
The Oregon case is particularly intriguing because it involved HPP-treated food. However, updated information tells us that unopened bags from the same lot tested negative for H5N1, meaning it was likely not a manufacturing contamination issue. Regardless of this fact, we need more research to understand:
– The effectiveness of different processing methods against H5N1
– The relationship between viral DNA detection and actual infection risk
– The role of manufacturing environments in potential contamination
– The presence of viral material across all pet food categories, including processed foods
Moving Forward: A Call for Better Research
Rather than rushing to broad conclusions, the pet food industry needs:
- Standardized testing protocols that differentiate between live and killed virus
- Comprehensive surveys across all pet food categories
- Better understanding of transmission routes and risk factors
- Research into effective control measures that preserve nutritional quality
A Balanced Perspective
While H5N1 deserves serious attention, we must resist the urge to draw sweeping conclusions from limited data. The current situation highlights the need for better research, testing, and regulation across all pet food categories – not just raw products.
At NorthPoint Pets, we believe in making decisions based on complete evidence rather than reaction to headlines. We continue to monitor the situation closely and will adjust our recommendations as more conclusive evidence emerges. In the meantime, we encourage pet owners to stay informed, consider multiple perspectives, and make decisions based on their individual circumstances and risk tolerance.
We’re committed to transparency and will continue sharing information as our understanding evolves. Pet health is complex, and sometimes the most responsible position is acknowledging what we don’t yet know while working diligently to learn more.
This article reflects current understanding as of December 2024 and draws from international case reports and scientific literature. Our analysis may evolve as new evidence emerges.
[1] Truth About Pet Food Interview with Oregon Department of Agriculture. https://truthaboutpetfood.com/oregon-regulatory-finally-responds-to-questions-regarding-northwest-naturals/
[2] Isbarn, S., Buckow, R., Himmelreich, A., Lehmacher, A., & Heinz, V. (2007). Inactivation of Avian Influenza Virus by Heat and High Hydrostatic Pressure. Journal of Food Protection, 70(3), 667-673. https://doi.org/https://doi.org/10.4315/0362-028X-70.3.667
[3] Buckow, R., Bingham, J., Daglas, S., Lowther, S., Amos-Ritchie, R., & Middleton, D. (2017). High pressure inactivation of selected avian viral pathogens in chicken meat homogenate. Food Control, 73, 215-222. https://doi.org/https://doi.org/10.1016/j.foodcont.2016.08.003
[4] Barroso, S. P. C., Nico, D., Nascimento, D., Santos, A. C. V., Couceiro, J. N. S. S., Bozza, F. A., Ferreira, A. M. A., Ferreira, D. F., Palatnik-de-Sousa, C. B., Souza, T. M. L., Gomes, A. M. O., Silva, J. L., & Oliveira, A. C. (2015). Intranasal Immunization with Pressure Inactivated Avian Influenza Elicits Cellular and Humoral Responses in Mice. PLOS ONE, 10(6), e0128785. https://doi.org/10.1371/journal.pone.0128785
