November 2026

When the rain stops and the water slowly drains from the streets, many families in Perambur, Kolathur, Vyasarpadi and nearby areas notice a new problem: someone in the house develops fever. After days of wading through dirty water, a fever with body pain should not be dismissed as a “normal monsoon fever”. Two infections deserve particular attention at this time of year: leptospirosis and typhoid. This article explains how to recognise the symptoms of each, how doctors confirm the diagnosis, and when it is time to stop waiting at home and see a doctor. Quick answer: can walking in flood water cause fever? Yes, it can. Flood water in a city often mixes with sewage and with the urine of rats, dogs and cattle. Leptospirosis is caused by bacteria that spread through such water. The bacteria can enter the body through cuts, scratches, softened skin on the feet, or through the eyes, nose and mouth. Typhoid is different. It spreads when food or drinking water is contaminated, which happens easily when drains overflow and water pipes are damaged. Both infections can begin with fever, so symptoms alone cannot tell them apart. A doctor’s examination and the right tests are what settle the diagnosis. What is leptospirosis? Leptospirosis is a bacterial infection that spreads from animals to humans. Rats are the most common source in cities. The bacteria pass out in animal urine and survive in stagnant water and wet soil. People are usually infected when they walk or work in such water, especially if they have open wounds.Leptospirosis symptoms The illness often begins suddenly. Common signs include: High fever with chills Severe headache Intense muscle pain, especially in the calves and lower back Redness of the eyes without pus or much discharge Nausea, vomiting or loose stools A skin rash in some people Many people recover with timely treatment. In a smaller number, the illness becomes serious. Warning signs of the severe form include yellowing of the skin and eyes, very little urine, swelling of the face or legs, breathlessness, coughing blood, or unusual bleeding. This severe form can affect the kidneys, liver and lungs and needs urgent hospital care. A useful clue is the combination of fever, body pain and red eyes after contact with flood water. If you notice this pattern, do not wait for it to pass. What is typhoid fever? Typhoid is caused by a bacterium called Salmonella Typhi. It spreads through food and water contaminated by the faeces of an infected person. After floods, street food, cut fruit, ice and untreated drinking water are common routes of spread. Typhoid symptoms Typhoid usually builds up gradually rather than starting suddenly. Common signs include: Fever that rises over several days and stays high Headache and tiredness Stomach pain and discomfort Constipation in some people, loose motions in others Loss of appetite Weakness that lingers How long does typhoid fever last? It depends on how early treatment begins. Without proper treatment, the illness can continue for weeks and may lead to complications. With the right antibiotics prescribed by a doctor, most people begin to improve within several days, but weakness can last longer. It is important to finish the full course your doctor prescribes, even after the fever settles. Stopping early can allow the infection to return. Leptospirosis vs typhoid: how they differ Feature Leptospirosis Typhoid How it spreads Contact with water or soil contaminated by animal urine Eating or drinking contaminated food and water Typical start Often sudden Usually gradual Distinctive signs Severe calf pain, red eyes, yellowing in serious cases Stepwise rising fever, stomach pain, marked weakness Key risk after rains Wading through flood water, especially with cuts Street food, unsafe water, poor hygiene during water shortages Serious complications Kidney, liver and lung involvement Intestinal bleeding or perforation, if untreated This table is a guide only. The two illnesses overlap, and dengue and malaria are also common after rains. That is why testing matters. How are these infections diagnosed? Please do not guess the cause of your fever. A doctor will first ask about your symptoms, when they began and whether you were exposed to flood water or unsafe food. After examining you, the doctor may advise some of the following tests. For leptospirosis: Blood tests that look for antibodies against the bacteria are commonly used. In the early days of illness, antibodies may not yet have developed, so the doctor may repeat a test later or use a test that detects the bacteria’s genetic material, where available. Kidney and liver function tests, and a complete blood count, help judge how severe the illness is. For typhoid: A blood culture is considered the more reliable test, ideally done before antibiotics are started. The Widal test is still widely used in India, but its result can be hard to interpret, so doctors read it alongside symptoms and other findings. To rule out other causes: Tests for dengue and malaria are often done at the same time, because the early symptoms look similar. How are leptospirosis and typhoid treated? Both are bacterial infections and are treated with antibiotics chosen and prescribed by a doctor. The right medicine depends on the diagnosis, how unwell the person is, other health conditions, and local resistance patterns. This matters especially for typhoid, where some strains no longer respond to commonly used antibiotics. Please avoid taking leftover antibiotics or buying them without a prescription. Wrong or incomplete treatment can hide the illness, delay the correct diagnosis and encourage resistant bacteria. Mild cases may be managed at home with close follow-up, rest and plenty of fluids. Hospital admission may be needed when there is persistent vomiting, dehydration, jaundice, breathing difficulty, reduced urine, bleeding or confusion. Not everyone needs admission, but anyone with these signs should be seen urgently. When to see a doctor See a doctor promptly if you have fever after wading through flood water, especially if it comes with body pain, red eyes, vomiting or severe headache. Do not wait for several days to