A recent report from the Centers for Disease Control and Prevention (CDC) reveals a notable increase in tularemia, commonly known as "rabbit fever," cases across the United States. This disease, caused by the bacteria Francisella tularensis, typically affects rabbits, hares, and rodents but can transmit to humans, making it a zoonotic illness.

While tularemia is relatively uncommon, with just over 2,400 diagnoses between 2011 and 2022, the CDC's Morbidity and Mortality Weekly Report indicates a 56% rise in cases compared to the preceding decade. This begs the question: are we witnessing a genuine surge in infections, or are enhanced detection methods playing a role?

The CDC report acknowledges that the increase in reported cases might stem from either a true rise in human infections or improved diagnostic capabilities, or perhaps a combination of both. Dr. Daniel Ruderfer, chief of Pediatric Infectious Diseases at Hackensack Meridian K. Hovnanian Children's Hospital, suggests that advancements in microbiology detection methods are a significant factor. He points out that traditional diagnostic methods relied on culture growth and antibody testing, while newer PCR testing likely contributes to the higher number of reported cases.

Humans can acquire tularemia through various routes, including bites from deer flies or ticks, direct contact with infected animals, or exposure to contaminated water or aerosols. Symptoms can manifest differently depending on the disease's form, ranging from general symptoms like chills, headaches, fatigue, and muscle aches to more specific issues such as enlarged lymph nodes, skin ulcers at the infection site, conjunctivitis, pneumonia, and even bloodstream infections.

Although the fatality rate for tularemia is generally low, below 2%, severe cases can see mortality rates as high as 24%, according to the CDC. Antibiotics are effective in treating the infection, but no vaccine is currently available. Dr. Ruderfer emphasizes the potential severity of the infection, stressing that it can be life-threatening if not treated promptly with the right antibiotics.

Certain groups face a higher risk of tularemia, including children aged 5 to 9, older men, American Indian and Alaskan Native individuals, and residents of central U.S. states. The CDC suggests that factors such as the geographic distribution of Native American reservations and specific sociocultural or occupational activities that increase contact with infected wildlife or arthropods could contribute to this elevated risk. While the general population's risk is relatively low unless they have direct contact with infected animals or vectors, individuals who hunt or frequently interact with rabbits are advised to seek medical attention if they experience any concerning symptoms.