Leptospirosis

What is leptospirosis?

Leptospirosis is an infection caused by bacteria known as leptospires, which affect both humans and animals. Humans become infected through contact with the urine of infected animals such as cattle, pigs, dogs, and especially rats. Infection occurs when someone comes into contact with the urine of sick animals or with contaminated water and soil, particularly during periods of flooding.

Symptoms

Symptoms of leptospirosis can range from mild, flu-like signs to more severe manifestations. As the disease progresses, additional signs may appear, such as jaundice (yellowing of the skin and eyes), kidney failure, and bleeding.
 

The incubation period for symptoms can vary from two to 30 days (typically seven to 14 days) after exposure to contaminated areas. Common symptoms include:

• high fever
• headache
• muscle pain (especially in the calves)
• chills
• vomiting
• diarrhea
• red eyes
• yellowing of the skin and eyes (in severe cases)

It is important to seek medical attention if leptospirosis is suspected, especially after being in an area where the disease is common. Early detection and treatment are crucial to avoid complications.

Causes

Infection occurs when the bacteria enter a person’s body, and certain conditions facilitate its spread:

• skin injuries or wounds
• contact with mucous membranes (such as eyes, nose, and mouth)

Person-to-person transmission is rare. Leptospirosis is transmitted from animals to humans through contact between animal urine and broken human skin.

Diagnosis

Because leptospirosis shares symptoms with other diseases, diagnosis requires the patient to provide detailed information to the doctor, including recent travel, occupational risks, and exposure to animals or contaminated water.

Definitive diagnosis requires laboratory tests, typically involving blood samples. These samples are analyzed to detect the presence of leptospira bacteria or antibodies produced by the immune system. While awaiting definitive results, other lab tests—such as blood count, kidney and liver function tests—can help assess the severity of the disease.

Treatment

Treatment for leptospirosis generally involves antibiotics such as doxycycline or penicillin, prescribed by a doctor. In severe cases, hospitalization for intensive care may be necessary.

Prevention

Leptospirosis bacteria can survive for months depending on environmental conditions (temperature, humidity, mud, or surface water), but they are sensitive to common disinfectants. Disinfecting water reservoirs with bleach (2.5% sodium hypochlorite) is one way to prevent the disease. Additional preventive measures include:

• avoiding contact with potentially contaminated water or soil, especially after floods
• using protective equipment like gloves and boots when handling contaminated water or soil
• controlling rodent populations in urban areas and reducing garbage accumulation
• thoroughly washing hands and body parts that may have come into contact with contaminated water or soil
• properly storing food to prevent contamination by rodent urine

References

World Health Organization
Telessaúde Unifesp
Brazilian Ministry of Health – BVSMS
Brazilian Ministry of Health – Health from A to Z
Brazilian Ministry of Health – Floods and Inundations FAQ
Bahia Health Department
Government Portal of the State of Rondônia

By Einstein Editorial Board