Plague

The most common mode of transmission Y. pestis to humans is by the bite of infectious fleas, especially the Oriental rat flea (X. cheopis).

Less frequently, infection is caused by direct contact with infectious body fluids or tissues while handling an infected animal or inhaling infectious respiratory droplets.

Outbreaks of plague in humans usually involve exposure to house rats and their fleas. Risk for plague in humans is greatest when epizootics cause high mortality in rat populations, forcing hungry, infected rat fleas to seek alternative hosts such as humans.

Human plague cases in the U.S. have been sporadic cases acquired from wild rodents or their fleas or from direct contact with plague-infected animals. Rock squirrels, ground squirrels, prairie dogs, wood rats, and chipmunks have served as sources of human infection.

Signs and symptoms include fever, headache, myalgia (muscle aches), malaise, shaking chills, prostration, and gastrointestinal symptoms.

The three principal clinical presentations of plague are bubonic, septicemic, and pneumonic.

• Bubonic is the most common, with an incubation period from 2-6 days, and is characterized by the development of an acute regional lymphadenopathy (swollen lymph nodes), or bubo. The case-fatality rate for untreated individuals is 50-60%.
• Septicemic disease occurs when Y. pestis invades and multiplies in the bloodstream. This can occur secondarily to the bubonic form or develop without detectable lymphadenopathy.
• Pneumonic plague is the least common, but most fatal, form of the disease. It can develop either as a secondary complication of septicemia or result from inhalation of infectious respiratory droplets expelled from a human or animal that has the pneumonic form. The incubation period for primary pneumonic plague is 1-3 days.

Several antibiotics may be used for prophylactic therapy in persons exposed to Y. pestis, although streptomycin is the drug of choice. An inactivated vaccine is also available.

Wild rodents can cause home damage, contaminate food, and cause illness in people and pets.

Rodent infestations are more likely to occur when events such as flooding displace them.

To avoid rodent infestation remove potential rodent food and water sources, and store food for people and pets in sealed containers.

Clear debris and other material that rodents can hide in. 

Safely clean-up rodent droppings, urine and nesting areas, always wearing gloves and spraying material with disinfectant until thoroughly soaked before attempting to remove or clean.

Angiostrongylus/Rat Lungworm is a parasitic worm of rats that is present in some parts of the U.S. including Florida. Infected rats produce the parasite in their feces and can infect slugs and snails that eat rat feces. The parasite cycle is continued when another rat then eats an infected slug or snail.

Uncommon infections in people can occur when they eat raw or undercooked infected snails or slugs. Infections in people may not cause any illness or may cause a mild illness with muscle aches and non-specific symptoms that resolves within a few days. Less commonly, infections can result in meningitis.

Hantavirus is present in rodents throughout the U.S., and has been identified in cotton rats in Florida. Most human cases of hantavirus have been occurred in the western U.S., although cases have also occurred in the east. Hantavirus infection occurs when you breathe in virus-containing particles from rodent urine, droppings, or saliva that are stirred into the air. It is important to insure good ventilation and to avoid actions that raise dust when working in areas where rodents have been; activities to be avoided include sweeping or vacuuming.

Leptospirosis is caused by bacteria carried by many different kinds of animals, including cattle, pigs, horses, dogs, rodents, raccoons, and other wild animals. People can become infected through contact with water, food, or soil containing urine from an infected animal. Contact with contaminated material and cuts or breaks in the skin can also result in infection.

Flooding events (contaminated water) have been associated with multiple cases of illness in other countries, but has only rarely been seen in the U.S. Many infected people experience mild or no illness while for others the disease can be severe or life-threatening.

Lymphocytic choriomeningitis is a viral infection that can be found in wild rodents, primarily the common house mouse. Infection in commercially obtained pet rodents from reputable dealers is unusual; however pet rodents can become infected by exposure to wild mice. People can become infected after exposure to urine, droppings, saliva, or bedding of infected rodents.

The virus can be transmitted from pregnant women to their fetus and can cause fetal death as well as severe birth defects while the mother experiences very mild or no signs of illness. Pregnant women should not handle rodents and should avoid being in the same room as rodents or being in an area where rodent contaminated materials are being cleaned.

Rabies is extremely uncommon in small rodents such as mice, rats, and squirrels. Cases are occasionally seen in larger rodents, particularly woodchucks (not present in Florida).

To prevent exposure to rabies, avoid direct contact with wildlife and vaccinate dogs, cats, ferrets, and livestock. If you are bitten by a rodent or any other animal, seek medical attention from your health care provider.

Rat Bite Fever is caused by bacteria that is common in the upper respiratory tracts and mouths of healthy appearing rodents, especially rats. People are infected most commonly through bites or scratches, and may also become ill after eating food or drink contaminated with rodent droppings or through close contact with rodents.

Salmonellosis is an infection with Salmonella bacteria. It is most commonly associated with insufficient hygiene or inadequately cooked food, but can also be acquired from animals. Salmonella bacteria may be found in the feces of many animals, including pets.

Reptiles (turtles, snakes, lizards, etc.) and birds commonly carry Salmonella without signs of illness.