What are the other Names for this Condition? (Also known as/Synonyms)

• Infection due to Leptospira
• Mud Fever
• Rice-Field Worker's Disease

What is Leptospirosis? (Definition/Background Information)

• Leptospirosis is a caused by bacteria of the genus Leptospira. The disease affects humans as well as animals. The bacteria are ubiquitous and therefore, the disease is known to occur worldwide. However, the disease is reported to be more prevalent in temperate and tropical climates
• Leptospirosis affects individuals working outdoors or those in close contact with animals, such as farmers, veterinarians, miners, and slaughterhouse and fisheries workers. Apart from working outdoors or being exposed to animals, certain activities, such as swimming and kayaking in contaminated waters, are risk factors for contracting the disease
• The causative organism Leptospira is found in the urine of infected domestic and wild animals, such as pigs, rodents, cattle, and dogs. Individuals could get infected either during direct contact with infected animals or their body fluids (with the exception of saliva), or through contaminated food, water, or soil
• The symptoms reported in humans overlap with those for many other conditions and cover a wide spectrum. Some common symptoms are fever, chills, sore throat, headaches, muscle aches, nausea and vomiting. Potential complications from Leptospirosis include kidney damage, liver failure, and meningitis
• Antibiotics are the standard treatment for those who are infected with the bacterium and show symptoms of Leptospirosis. The prognosis is considered to be good. However, if the condition is not treated promptly, complications could make it life-threatening
• Avoiding stagnant waters and wearing protective clothing and footwear while handling animals are some methods to prevent contracting Leptospirosis

Who gets Leptospirosis? (Age and Sex Distribution)

• Leptospirosis affects humans and animals alike. The disease occurs globally, more so in tropical and temperate climates
• Those who frequently come in contact with animals, and those who work predominantly outdoors, are considered more susceptible to infection, irrespective of age and gender

What are the Risk Factors for Leptospirosis? (Predisposing Factors)

The risk factors for Leptospirosis include occupations and activities such as:

• Farming
• Logging
• Mining
• Working in the sewers
• Veterinarians; animal caretaking
• Working in slaughterhouses, fisheries
• Working in the military
• Swimming or kayaking in contaminated waters
• Outdoor camping and sporting activities

Apart from the above, living in or visiting places with warm climates, and situations, such as floods, where one might be forced to consume contaminated waters, are risk factors for Leptospirosis.

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Leptospirosis? (Etiology)

Bacteria belonging to the genus Leptospira cause Leptospirosis. The bacteria are present everywhere and are capable of surviving in water and soil.

• When animals get infected, their urine harbors the bacteria. Any individual who comes in direct contact with the body fluids of infected animals could potentially contract the disease
• The disease could also spread through contact with contaminated soil or water, by way of one’s occupation, through recreational activities, or even during floods
• The bacteria could gain entrance to the human body through mucous membranes of the eye and nose, or through cuts/breaks in the skin
• Animals are reported to release the bacteria in their body fluids either continuously or sporadically and could continue to do so over several months. The animals known to get infected with Leptospira sp. are the following:
  • Domestic and farm animals like cattle, dogs, pigs, horses, etc.
  • Rodents
  • Wild animals
• The disease is not generally known to spread from one individual to another

What are the Signs and Symptoms of Leptospirosis?

When an individual gets infected with Leptospira sp, it might take anywhere between 2-26 days for symptoms to develop. The symptoms could appear suddenly and overlap with those of other illnesses. The most common symptoms of Leptospirosis are also reportedly the first phase of the disease:

• Muscle pain
• Fever
• Headache
• Cough (non-productive)
• Gastrointestinal (GI) symptoms such as nausea, vomiting, and diarrhea
• Shaking chills

The affected individuals might start feeling better, but could feel ill again with additional, more serious symptoms during the second phase of the illness. The second phase, which is relatively uncommon, might have symptoms that include:

• Rashes
• Reddening of eyes; pink eyes (conjunctivitis)
• Abdominal pain
• Joint pain, bone pain, and stiff muscles
• Sore throat, abnormal lung sounds
• Swollen lymph glands
• Jaundice

The second, more serious phase is termed “Weil’s Disease” and could involve liver failure, kidney failure, or meningitis.

How is Leptospirosis Diagnosed?

The standard test for the diagnosis of Leptospirosis is a blood test to check for antibodies to Leptospira species. A healthcare professional may opt to request more tests depending on the signs and symptoms. Such tests might include:

• Complete blood count (CBC)
• Creatine kinase (to check muscle health)
• Liver enzymes (for assessing liver health)
• Urinalysis (to assess kidney health)

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Leptospirosis?

Some potential complications from an infection leading to Leptospirosis could include:

• Liver failure; kidney failure
• Enlarged spleen
• Meningitis
• Severe bleeding
• An adverse reaction to penicillin (antibiotic) used in the treatment

How is Leptospirosis Treated?

The standard treatment for Leptospirosis is antibiotics, belonging to the tetracycline (such as doxycycline) or β-lactam (such as penicillin) families.

• Oral antibiotics are generally prescribed for the early phase of Leptospirosis
• Patients are advised to complete their antibiotics regimen, even if they start feeling better after taking a few doses of the prescribed medication
• When an individual exhibits more severe symptoms, intravenous antibiotics may be prescribed

How can Leptospirosis be Prevented?

Currently, there is no vaccine available for preventing Leptospirosis. However, the following measures could help reduce the possibility of contracting the disease:

• Avoiding swimming or other water sports in stagnant water bodies that could be contaminated with urine from Leptospira sp. infected animals
• Avoiding direct contact with potentially infected animals. If contact with potentially infected animals or contaminated soil is not avoidable, wear suitable protective clothing to help minimize risk
• Avoiding ingestion of potentially contaminated water
• Attend to cuts and wounds on skin promptly, especially if you work outdoors or take part in outdoor sports activities
• If traveling, talking to a healthcare provider about taking prophylactic medication might be of assistance
• Seek medical help if you suspect exposure to Leptospira sp.; this could help minimize progression of infection and symptoms

What is Prognosis of Leptospirosis? (Outcomes/Resolutions)

• The prognosis of Leptospirosis is generally good, if the infection is diagnosed early and treated promptly
• However, Leptospirosis can be a life-threatening infection if complications, such as organ failure or meningitis, occur

Additional and Relevant Useful Information for Leptospirosis:

• Among the numerous diseases that get transmitted from animals to humans, Leptospirosis is reported to be the most widespread
• In the USA, approximately 100-200 cases of Leptospirosis are reported annually. About half of these cases are reported from Hawaii