What is ‘rabbit fever’, the rare disease up by 56% in the US? Signs and symptoms explained

Tularemia, also commonly known as ‘

rabbit fever

‘ has witnessed more than 50 per cent rise in the US in recent years, as per a recent report.
A rare and sometimes deadly infectious disease is seen in children between the 5-9 years age group, older men, and American Indians or Alaska Natives. The bacteria has been designated a Tier 1 Select Agent, or the highest risk category, based on its potential for use as a bioweapon.
Tularemia is caused by the bacterium

Francisella tularensis

and can infect animals and people. Rabbits, hares and rodents are more likely to get the disease. People can also become infected in many ways, including tick and deer fly bites, and contact with infected animals like rabbits, rodents, and hares.
The infection can also spread by drinking contaminated water and inhaling contaminated aerosols or agricultural and landscaping dust, and laboratory exposure, as per CDC.

The years 2011 and 2022 have witnessed 56 percent rise in the annual average incidence of tularemia infections compared with previous years from 2001 to 2010, as per Centers for Disease Control and Prevention (CDC).

A report published in Morbidity and Mortality Weekly Report said that more than 2,400 cases were reported during the more recent time frame.
Most of the cases reported by 47 states came from just four. Around half were reported in Arkansas, Kansas, Missouri, and Oklahoma.

The huge jump may be attributed to increased reporting of probable cases as per the agency.
“These findings might reflect an actual increase in human infection or improved case detection amid changes in commercially available laboratory tests during this period,” the report’s authors said.

Signs and symptoms of Tularemia or rabbit fever

The illness can be mild or severe and high grade fever is a common symptom in all kinds of illnesses. The signs and symptoms of tularemia can depend on how the bacteria has entered the body. Here are some of them mentioned by CDC.

Skin ulcer

The most common symptom that is observed after a tick or deer fly bite or after handing of an infected animal is a skin ulcer that appears at the site where the bacteria entered the body. The ulcer is accompanied by swelling of regional lymph glands, usually in the armpit or groin. It is called ulceroglandular tularemia. Another form without the ulcer is called glandular tularemia.

Irritation and inflammation in eyes

This form is called oculoglandular and occurs when the bacteria enter through the eye. A person may be infected by it while butchering an infected animal or contact with their eyes. Symptoms include irritation and inflammation of the eye and swelling of lymph glands in front of the ear.

Sore throat, mouth ulcer

Another way the virus spreads is through eating or drinking contaminated food or water. Patients with orophyangeal tularemia may report sore throat, mouth ulcers, tonsillitis, and swelling of lymph glands in the neck.

Difficulty in breathing

The most severe form of the infection, its symptoms include cough, chest pain, and difficulty breathing. This happens when someone breaths dusts or aerosols containing the organism. It can also happen when other forms of tularemia are left untreated and the bacteria spread through the bloodstream to the lungs.

How to prevent the infection

Carrying insect repellants can help prevent tick and insect bites.
Covering body by wearing long sleeves and long pants can help keep ticks and deer flies away.
Remove attached ticks promptly with fine-tipped tweezers.
Don’t drink untreated surface water.
One should wear masks during mowing and other such activities to reduce risk of inhaling the bacteria.
Use gloves when handling rabbits, muskrats, prairie dogs, and other rodents.
Cook game meat thoroughly before eating.
Vaccination for tularemia is not yet available in the U.S. The illness is treatable with antibiotics, and the case fatality rate is typically less than 2 percent. However, it may be as high as 24 percent.

(Picture courtesy: iStock)