The cat-borne parasite “Toxoplasma gondii” can adversely affect humans.

In a groundbreaking study recently published in the Journal of Gerontology: Medical Science, a group of international scientists, including researchers from the University of Colorado Boulder, delved into the microscopic world of Toxoplasma gondii (T. gondii). The cat-borne parasite is notorious for its connections to risk-taking behavior and mental health issues in humans. However, this time, the focus was on the potential contribution of T. gondii to the signs of frailty in older adults, including exhaustion and muscle loss.

Human Contact with T. Gondii Is Common

Often perceived as a relatively benign infection, T. gondii’s impact on human health is far more complex than previously thought, with the study shedding light on its potential consequences for aging individuals. Approximately 11% to 15% of the U.S. population has encountered T. gondii at some point, and rates are notably higher among older individuals, reaching over 65% in certain countries.

Connection Between Infection and Frailty

The research, involving 601 Spanish and Portuguese adults over the age of 65, investigated the relationship between T. gondii and frailty – a geriatric syndrome encompassing unintentional weight loss, fatigue, cognitive decline, and other signs of declining health. While the study did not establish a direct association between T. gondii infection and frailty, it did unveil a noteworthy connection. Among those infected, individuals with higher “serointensity” or a heightened concentration of antibodies to the parasite were significantly more likely to exhibit frailty.

The study’s lead author, Christopher Lowry from the Department of Integrative Physiology at CU Boulder, emphasized the significance of these findings, suggesting that T. gondii infection might have more profound health consequences than previously acknowledged. Rather than confirming a causal relationship, the study identified a compelling association, prompting further exploration into the intricate dynamics between T. gondii and frailty.

T. Gondii and Age-Related Inflammation

Notably, the researchers discovered that frail individuals with elevated T. gondii seropositivity also displayed heightened levels of inflammatory markers. This suggests that T. gondii infection might exacerbate age-related inflammation, commonly referred to as “inflammaging.” Given that T. gondii tends to hide in muscle tissue, the researchers propose that it could contribute to sarcopenia, the age-related loss of muscle mass.

While the study doesn’t conclusively establish T. gondii as the cause of frailty, it highlights a correlation that warrants deeper investigation. The researchers hope their findings will spur further research into the relationship between T. gondii and frailty, potentially uncovering new avenues for mitigating its impact.

Infection Prevention

In the interim, the researchers advise caution, especially for pregnant and immunocompromised individuals, urging preventive measures such as daily litter box changes, thorough handwashing, avoidance of undercooked meat, and meticulous fruit and vegetable rinsing. The study opens up a fascinating realm of exploration, offering a fresh perspective on the intricate interplay between feline parasites and the aging process in humans.