Learn about leptospirosis, including its symptoms, diagnosis, laboratory tests, treatment and prevention.
Infectious Disease
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Multiple organ systems
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Overview
Leptospirosis is a bacterial infection caused by Leptospira species, pathogenic spirochetes that inhabit the kidneys of infected animals including rats, mice, cattle, pigs, and dogs. These animals shed the bacteria in their urine continuously without becoming ill themselves , they are asymptomatic carriers. Transmission to humans occurs when contaminated animal urine comes into contact with broken skin, mucous membranes, or intact skin exposed to water for prolonged periods.
Unlike typhoid fever, which is transmitted exclusively human-to-human through the fecal-oral route, leptospirosis is an environmental zoonotic disease , it is maintained in animal populations and spills over into humans through water contact. This distinction is clinically important: leptospirosis risk is highest during flooding events and rainy seasons when rainwater becomes contaminated with infected animal urine, and when people wade through standing water.
In Ghana, leptospirosis is recognized as an important occupational disease for farmers, fisherfolk, veterinarians, and slaughterhouse workers who have regular water exposure. It is also a disease of poverty and informal urban settlements where flooding forces residents to wade through contaminated water. The WHO estimates leptospirosis causes approximately one million cases and 58,900 deaths annually worldwide, with the majority of this burden in tropical and subtropical regions including West Africa.
The incubation period ranges from two to thirty days, with most cases presenting within five to fourteen days of exposure to contaminated water.
The classic clinical presentation is biphasic fever: an initial illness phase lasting three to ten days followed by apparent recovery for a few days, then a second phase of illness. However, this biphasic pattern is not always present, and many cases present as a single continuous febrile illness, creating diagnostic confusion with malaria, typhoid, or dengue fever.
Disease Summary
Category
Infectious Disease
Cause
Leptospira interrogans (and other Leptospira species)
Transmission
Contact with contaminated water or soil
Body System
Multiple organ systems
Preventable
Yes
Curable
Yes
Symptoms
Common Symptoms (First Phase)
The first phase of leptospirosis typically lasts three to ten days. Symptoms are non-specific and resemble many other febrile illnesses.
Abrupt Fever
Fever appears suddenly and can reach 39 to 40 degrees Celsius. Unlike the gradual step-ladder fever of typhoid, leptospirosis fever onset is abrupt, more resembling malaria.
Severe Headache
A prominent headache, often severe, is present in most cases and may be accompanied by pain behind the eyes.
Muscle and Joint Pain
Muscle pain (myalgia) is prominent and often severe, particularly in the calf muscles and lower back. This muscular pain is one of the distinguishing features of leptospirosis.
Chills and Sweating
Rigors (chills) and profuse sweating are common and can resemble malaria fever episodes.
Nausea, Vomiting, and Abdominal Pain
Gastrointestinal symptoms including nausea, vomiting, and abdominal pain are common.
Fatigue and Malaise
Profound weakness and a general feeling of being unwell accompany the fever.
Second Phase Symptoms (If Biphasic)
Some patients experience apparent recovery for a few days, followed by a second phase of illness lasting days to weeks.
Return of Fever
If biphasic illness occurs, fever returns during the second phase, sometimes higher than the first phase.
Aseptic Meningitis Symptoms
The second phase may include severe headache, neck stiffness, and photophobia (sensitivity to light) suggesting meningeal involvement, though this is typically aseptic (no bacteria in the cerebrospinal fluid).
Eye Redness (Conjunctival Suffusion)
Redness of the whites of the eyes without discharge is a characteristic finding of the second phase and is one of the features that can help distinguish leptospirosis from other febrile illnesses.
Danger Signs
Seek urgent medical attention immediately if any of the following symptoms develop. These may indicate severe leptospirosis (Weil's disease).
Jaundice
Yellowing of the skin or eyes indicates liver involvement and may signal progression to Weil’s disease, the severe form of leptospirosis.
Kidney Dysfunction Symptoms
Decreased urination, dark-colored urine, or swelling of the face and ankles may indicate kidney injury.
Respiratory Symptoms
Cough, difficulty breathing, or coughing up blood may indicate pulmonary involvement.
Bleeding
Spontaneous bleeding, blood in vomit or stool, or bruising without trauma indicates severe thrombocytopenia or coagulopathy.
Altered Mental State
Confusion, excessive drowsiness, or reduced consciousness may indicate meningeal involvement or renal failure.
Diagnosis
Clinical Assessment
Diagnosis begins with a detailed history including water exposure history, occupational exposure, and travel. Healthcare professionals assess the pattern of fever, presence of muscle pain, conjunctival suffusion (eye redness), and whether symptoms follow the characteristic biphasic pattern. However, no combination of clinical features is specific for leptospirosis , many of these findings are shared with malaria, typhoid, and dengue.
Physical Examination
The examination may reveal conjunctival suffusion without discharge (redness of the eyes without eye discharge), a finding that is relatively specific for leptospirosis. Rash, if present, is typically not prominent. Jaundice and signs of kidney or liver dysfunction may be present in severe cases.
Laboratory Confirmation
Laboratory testing is essential for confirming leptospirosis. Blood culture and PCR are useful in the first week of illness. Serology (antibody testing) becomes more useful from the second week onward.
Laboratory Tests
Blood Culture
Blood culture can detect Leptospira in blood during the first week of illness (the leptospiremic phase) and is the only culture method for leptospirosis diagnosis. Special media (like EMJH medium) are required. A positive blood culture confirms leptospirosis diagnosis but requires appropriate media and expertise that may not be available in all Ghanaian facilities.
Sample
Venous blood
Time
3 to 7 days
PCR (Polymerase Chain Reaction)
PCR can detect Leptospira DNA in blood during the first week of illness and is highly specific and sensitive. It is faster than culture and is becoming more available in reference laboratories. A positive PCR result confirms leptospirosis infection.
Sample
Venous blood or cerebrospinal fluid
Time
Same day to 24 hours
IgM Antibodies
IgM antibodies appear around day five to seven of illness and are detectable for approximately three to four months. The presence of IgM indicates recent or acute leptospirosis infection. This test becomes the primary diagnostic test from the second week of illness onward when blood culture and PCR sensitivities decline.
Sample
Venous blood (serum)
Time
24 to 48 hours
Microscopic Agglutination Test (MAT)
The MAT is a reference serological test that detects antibodies against specific Leptospira serovars. It can identify which serovar is causing infection, which is valuable for epidemiological purposes. However, it requires specialized laboratory expertise and is available only in reference centers, not in most Ghanaian primary health facilities.
Sample
Venous blood (serum)
Time
24 to 48 hours
Complete Blood Count (FBC)
The complete blood count may reveal elevated white blood cell count, low platelet count, and anemia in more advanced disease. These findings are non-specific but can support a diagnosis of leptospirosis when interpreted in clinical context.
Sample
Venous blood
Time
1 to 3 hours
Treatment
Doxycycline
Doxycycline is the first-line antibiotic for leptospirosis. It is most effective when started early, ideally within the first week of illness. Adults receive 100mg twice daily for seven days. Doxycycline is inexpensive and widely available in Ghana. It is effective against leptospirosis and significantly reduces disease severity and complications when given early.
Route
Oral
Duration
7 days
Amoxicillin
Amoxicillin is an alternative oral antibiotic used when doxycycline is contraindicated (such as in children or pregnant women). Adults receive 500mg three times daily for seven days.
Route
Oral
Duration
7 days
Ceftriaxone
Ceftriaxone is used for severe leptospirosis requiring hospitalization, for patients who cannot tolerate oral medications, or for those with signs of Weil’s disease (jaundice, renal failure, pulmonary hemorrhage). It provides superior outcomes compared to oral antibiotics in severe disease.
Route
Intravenous
Duration
5 to 7 days
Supportive Care
Supportive care includes maintaining hydration, managing fever and pain, and in severe cases, managing kidney or liver failure. Close monitoring of kidney function and electrolytes is important, particularly in severe leptospirosis.
Route
Oral and Intravenous
Duration
Throughout illness
Prevention
Avoid Contact With Contaminated Water
Avoiding wading or swimming in water that may be contaminated with animal urine, particularly standing water, flood water, and water in areas with significant rat or livestock presence, reduces transmission risk.
Use Protective Equipment
For occupational water exposure (farmers, fisherfolk, veterinarians), wearing waterproof gloves, boots, and protective clothing reduces the risk of direct contact with contaminated water.
Maintain Personal Hygiene
Thorough washing of hands and any skin that may have contacted potentially contaminated water reduces infection risk.
Control Rodents and Livestock
Community-level rodent control and proper livestock management reduce the reservoir of Leptospira in the environment.
Leptospirosis Vaccination
Leptospirosis vaccines are available in some countries for high-risk occupational groups, though vaccine availability in Ghana is limited. Vaccines provide protection against specific serovars but not all serovars.
Risk Factors
Water and Environmental Exposure Risk Factors
These exposures directly increase transmission risk.
Wading or swimming in water contaminated with infected animal urine
Occupational water exposure (farming, fishing, veterinary work, slaughterhouses)
Living in areas prone to flooding with standing water exposure during rainy season
Living in or near informal settlements where flooding forces water contact
Inadequate access to clean water forcing reliance on potentially contaminated sources
Occupational Risk Factors
People in these occupations have documented higher leptospirosis rates.
Farmers and agricultural workers
Fisherfolk and aquaculture workers
Veterinarians and livestock handlers
Slaughterhouse and butcher workers
Sanitation workers
Individual and Seasonal Risk Factors
These conditions increase infection likelihood.
Rainy season (peak leptospirosis transmission season)
Flooding events
Working outdoors in wet environments
Broken skin or cuts that increase bacterial entry
Crowded living conditions in flood-prone areas
Complications
Weil's Disease (Severe Leptospirosis)
Weil’s disease represents severe leptospirosis with multi-organ involvement and a case fatality rate of 5 to 15 percent even with treatment. It is characterized by the triad of jaundice, renal failure, and pulmonary hemorrhage, though any combination of organ involvement may occur. It typically develops during the second phase of illness but can occur during the first phase. Early recognition and intensive management are essential.
Aseptic Meningitis
Leptospirosis can cause meningitis (inflammation of the membranes surrounding the brain and spinal cord). The cerebrospinal fluid shows elevated white cells but no bacteria on culture, hence “aseptic” meningitis. This typically occurs during the second phase of illness and presents with severe headache, neck stiffness, and photophobia.
Pulmonary Hemorrhage
Leptospirosis can cause bleeding into the lungs, presenting with hemoptysis (coughing up blood), dyspnea (shortness of breath), and potentially respiratory failure. This can develop during severe leptospirosis and requires urgent intensive care management.
Acute Kidney Injury
The kidneys are a primary target organ for leptospirosis. Acute kidney injury develops in approximately 50 percent of severe cases and may require temporary dialysis support. Most patients recover kidney function but some develop chronic renal impairment.
Liver Dysfunction and Jaundice
Liver involvement occurs during severe leptospirosis, presenting with jaundice (yellowing of skin and eyes), dark urine, and pale stool. Jaundice is one of the warning signs of progression to Weil’s disease.
When to Seek Medical Care
Fever Following Water Exposure
Any fever developing in the days to weeks after wading through flood water, occupational water exposure, or swimming in potentially contaminated water should raise suspicion for leptospirosis. Seek medical evaluation and specifically mention the water exposure history.
Fever With Prominent Muscle Pain
Fever accompanied by severe muscle pain, particularly in the calves and lower back, warrants evaluation for leptospirosis.
Red Eyes During Fever
Redness of the whites of the eyes (conjunctival suffusion) during a fever illness is a relatively specific sign for leptospirosis and should prompt testing for this condition.
Fever Not Responding to Antimalarial Treatment
If fever has been treated as malaria but is not improving, consider leptospirosis (or typhoid) and seek further evaluation and testing.
Warning Signs of Severe Leptospirosis
Seek urgent medical attention if any of the following develop: jaundice, dark urine, decreased urination, cough with blood, spontaneous bleeding, or altered mental state. These indicate progression to Weil’s disease or severe leptospirosis requiring intensive management.
Prognosis
Generally Excellent for Mild Leptospirosis
Most leptospirosis infections are mild, self-limited, and recover completely with or without treatment. With appropriate antibiotic treatment started early, outcomes are excellent and the illness resolves within one to two weeks.
Significantly Worse for Severe Leptospirosis (Weil's Disease)
Weil’s disease (severe leptospirosis) carries a case fatality rate of 5 to 15 percent even with intensive treatment. Early recognition, prompt antibiotic therapy, and access to intensive care including dialysis and respiratory support are critical for improving outcomes.
Recovery Often Takes Several Weeks
Even after acute illness resolves, some patients experience prolonged fatigue and weakness lasting weeks. Most recover completely, though some may develop chronic complications like chronic kidney disease if severe renal involvement occurred.
Differential Diagnosis
Malaria
Both malaria and leptospirosis present with abrupt fever and muscle pain, making early distinction difficult. Key differences: malaria typically presents with characteristic chills and sweating episodes; leptospirosis presents with persistent muscle pain more than chills. Conjunctival suffusion (red eyes) is characteristic of leptospirosis but absent in malaria. The biphasic fever pattern can occur in both. Laboratory testing for both is needed , a negative malaria test does not rule out leptospirosis, and the two can coexist.
Typhoid Fever
Typhoid develops gradually with a step-ladder fever pattern; leptospirosis typically has abrupt fever onset. Typhoid presents with constipation early; leptospirosis commonly presents with nausea and vomiting. Leptospirosis has prominent muscle pain; typhoid does not. History of water exposure points toward leptospirosis; history of contaminated food or water points toward typhoid. Laboratory testing can distinguish them.
Dengue Fever
Dengue also presents with abrupt high fever and muscle pain, particularly joint pain. Dengue presents with severe joint pain more prominent than leptospirosis. Dengue presents with a characteristic rash; leptospirosis typically does not. Dengue is transmitted by daytime Aedes mosquitoes; leptospirosis by contaminated water. A history of recent mosquito exposure suggests dengue; a history of water exposure suggests leptospirosis.
Pneumonia
Leptospirosis with pulmonary hemorrhage can present with cough and respiratory symptoms resembling pneumonia. However, leptospirosis typically presents with systemic symptoms including prominent muscle pain and fever before respiratory symptoms, whereas pneumonia typically presents with cough and respiratory findings more prominently. Laboratory testing can distinguish them.
World Health Organization comprehensive guidance on leptospirosis epidemiology, transmission, diagnosis, treatment, and prevention. Updated January 2024.
Comprehensive clinical reference for leptospirosis including diagnostic criteria, clinical management, and risk factors. Updated April 2025.
Frequently Asked Questions
How can I get leptospirosis if it's carried in rat urine?
Leptospirosis is transmitted when rat, mouse, or other animal urine comes into contact with your skin or mucous membranes. This happens when you wade through water or soil contaminated with animal urine. During flooding events, standing water becomes contaminated with urine from rats and other animals. When you walk through that water, the bacteria can enter your body through intact skin if you’ve been in water for prolonged periods, or more easily through cuts, scrapes, or abrasions on your skin.
You don’t have to be directly bitten by a rat to get leptospirosis. The bacteria survive in the environment for days to weeks in water and soil, particularly in warm, moist conditions. This is why leptospirosis is most common during rainy seasons and flooding events when people are forced to contact contaminated water.
My fever and muscle pain feel like malaria. How do I know if it's leptospirosis instead?
Early leptospirosis and malaria can feel very similar , both present with fever and muscle pain. A few features may help distinguish them:
Leptospirosis typically has very abrupt fever onset, whereas malaria can be more gradual. Leptospirosis causes particularly prominent muscle pain, especially in the calves and lower back. Malaria causes more characteristic chills and sweating episodes. Leptospirosis causes redness of the whites of the eyes without discharge; malaria does not typically produce this. Leptospirosis may have a biphasic pattern (fever resolves for a few days, then returns); malaria does not typically have this pattern.
However, you cannot reliably distinguish them based on these features alone. If you have had recent water exposure during flooding and developed fever with muscle pain, tell your healthcare provider about the water exposure and ask to be tested for leptospirosis alongside malaria testing. The two can coexist.
If I get leptospirosis, will I have permanent health problems?
Most people who get mild leptospirosis recover completely without any permanent problems. With early antibiotic treatment, recovery is rapid and complete for the vast majority of patients.
However, severe leptospirosis (Weil’s disease) can cause permanent organ damage. Severe kidney injury can lead to chronic kidney disease requiring long-term management. Severe liver involvement can lead to prolonged recovery of liver function. Some patients experience prolonged fatigue lasting weeks after acute illness.
The key is early diagnosis and treatment. Starting antibiotics early, even before laboratory confirmation if leptospirosis is suspected, reduces the risk of progression to severe disease and permanent complications.
Is there any way to know if water is contaminated with leptospirosis?
You cannot see or smell leptospirosis bacteria in water. You cannot tell by looking at water whether it contains leptospirosis or not. This is why the safest approach during floods or in areas known to have contaminated water is to avoid contact altogether if possible.
Any water that may have been contaminated with animal urine , including flood water, standing water in areas with rats or livestock, and water in rural agricultural areas , should be considered potentially contaminated. If you must be in contact with such water occupationally, use protective equipment including waterproof gloves and boots.
Can leptospirosis be spread from person to person?
Direct person-to-person transmission of leptospirosis is extremely rare. You cannot catch leptospirosis from being near someone with the disease or from touching them. The bacteria are shed primarily in urine, and direct contact with the urine of an infected person (which would be unusual) is required for transmission.
This is different from diseases like malaria or typhoid, which can spread person-to-person through mosquitoes or food/water respectively. Leptospirosis is essentially an environmental disease transmitted through contaminated water and soil, not through person-to-person contact.