A common misconception regarding Bartonella henselae infection, sometimes known as cat scratch disease (CSD), is that cats are the “bad guy” in the situation. Cats and other animals have been a part of human life for millennia and have documented positive effects on mental and physical wellness.
Cats are natural reservoirs for Bartonella henselae, and household pets may carry this and other Bartonella species as well as other pathogens. However, when it comes to Bartonella species, they’re not the vector. That is, they’re not what transmits the pathogen to humans. Transmission occurs when pets are exposed to fleas and infected flea feces finds its way under their nails or into their mouths during grooming. Once a scratch or bite occurs, the bacteria in the feces has access to the bloodstream of the human family member, leading to symptoms.
This distinction is important to understand because effective flea and tick preventatives are one way to greatly reduce the risk of families being exposed to harmful pathogens while keeping pets in the home. This means the human-animal bond can remain intact.
At Galaxy Diagnostics, we believe it is important to be aware of the risks living and working with animals pose to families, but it is equally as important to understand that disease transmission can be prevented.
We hear heartbreaking stories of the emotional and financial strain that vector-borne chronic illnesses put on individuals and their families. One result of this strain may be to remove pets from the household. However, this is not usually necessary because pets are not the root of the issue. It may even be counterproductive because of the role pets play in human emotional and physical health.
But why is this bond so important?
The human-animal bond is complex and can have multiple meanings depending on the group in question. For example, someone who relies on working animals for their livelihood will have a different relationship than a family that shares a pet for companionship. The Human-Animal Bond Research Institute (HABRI) defines the human-animal bond as a “mutually beneficial and dynamic relationship between people and animals that is influenced by behaviors that are essential to the health and well-being of both.”
For animals, this relationship may simply mean food and a warm place to sleep. For humans, the benefits animals provide are broad and deeply impactful on many fronts.
Mental Health
Hormone fluctuations that are related to stress relief, socialization, and more seem to be the foundation of the psychological benefits that human-animal interactions provide. Oxytocin, a hormone linked to promoting maternal care in mammals, increases when people of any age or gender interact with dogs and cats. When oxytocin levels are increased, stress hormones like cortisol and epinephrine are inhibited, resulting in physiological changes that positively affect psychological state.
These hormonal changes affect both people and their pets. A study of dogs interacting with their owners versus strangers found the level of oxytocin is greater when the dog sees their owner, showcasing the importance of a bond being present.
Companion animals also help facilitate social interactions that mitigate issues seen in patients struggling with long-term mental health problems. For patients that are in and out of hospitals due to chronic illness, therapy dogs provide a way to escape feelings of isolation.
A study of hospitalized heart disease patients who interacted with therapy dogs for just 12 minutes found they had a reduction in hospital-induced anxiety and were less likely to experience complications down the road.
Children experiencing psychological disorders such as schizophrenia at inpatient facilities were shown in another study to have better emotional control following therapy sessions with a dog present.
Physical Health
Animals can contribute to an increased exposure to allergens for children, and that’s good for them! Exposure to more allergens at a young age may influence the immune system later in life. The idea, part of the hygiene hypothesis, is that increased exposure to allergens earlier in life allows for natural development of the immune system. If exposure is limited, an inappropriate response to allergens, like peanuts or animal dander, could be more likely.
In a comparison study of 18-year olds who grew up with pets versus those who didn’t, there was a trend of lower IgE antibodies in response to common allergens such as dust mites and ragweed. A lot is still unknown about how the immune system is affected by pets, but being exposed to the microbial diversity that pets offer could be beneficial.
Pets have physical demands that can motivate owners to adopt more active hobbies. This can have drastic benefits for cardiovascular health of people who may not otherwise enjoy working out. For example, dog owners are 57% more likely to reach the recommended level of activity each day than non-pet owners.
Furthermore, cats have been shown to reduce blood pressure in their owners, resulting in reduced risk of strokes and other cardiovascular diseases. Even in places that do not normally have pets, like gyms, the motivation of members in fitness classes has been shown to be higher when dogs, cats, or even goats are present.
Conclusion
Humans and animals have evolved together to have a complex emotional relationship. Relationships with animals are one way to push back against the challenges post-industrialization lifestyles bring to staying healthy. When facing a challenge from Bartonella species or other pathogen infection, pets may be just what the doctor ordered.
References
Human Animal Bond Research Institute. (n.d.). What is the human animal bond? Retrieved from https://habri.org/about/
Miller, S. C., et al. (2009). An examination of changes in oxytocin levels in men and women before and after interaction with a bonded dog. Anthrozoös, 22(1), 31-42. https://doi.org/10.2752/175303708X390455
Pop, D. A., et al. (2014). Physiological effects of human-animal positive interaction in dogs: Review of the literature. Bulletin of University of Agricultural Sciences and Veterinary Medicine Animal Science and Biotechnologies, 71(2), 102-110. doi:10.15835/buasvmcn-asb:10398
Cole, K. M. (2007). Animal-assisted therapy in patients hospitalized with heart failure. American Journal of Critical Care, 16(6), 575-585.
Prothmann, A., et al. (2006). Dogs in child psychotherapy: Effects on state of mind. Anthrozoös, 19(3), 265-277. https://doi.org/10.2752/089279306785415583 https://www.tandfonline.com/doi/abs/10.2752/089279306785415583
Wegienka, G., et al. (2011). Lifetime dog and cat exposure and dog‐and cat‐specific sensitization at age 18 years. Clinical & Experimental Allergy 41(7), 979-986. https://doi.org/10.1111/j.1365-2222.2011.03747.x
Wegienka, G., et al. (2010). Indoor pet exposure and the outcomes of total IgE and sensitization at age 18 years. Journal of Allergy and Clinical Immunology, 126(2), 274-279. https://doi.org/10.1016/j.jaci.2010.05.001 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2917521/
Qureshi, A. I., et al. (2009). Cat ownership and the risk of fatal cardiovascular diseases. Results from the Second National Health and Nutrition Examination Study Mortality Follow-up Study. Journal of Vascular and Interventional Neurology, 2(1), 132-135. https://habricentral.org/resources/58614
Levine, G. N., et al. (2013). Pet ownership and cardiovascular risk. Circulation, 2013(127), 2353-2363. https://doi.org/10.1161/CIR.0b013e31829201e1 https://www.ahajournals.org/doi/full/10.1161/CIR.0b013e31829201e1