10 Monsoon Diseases To Watch Out For And How To Prevent Them

In Mumbai this July, the numbers tell their own story. Dengue cases have climbed from 734 to 938 since January, malaria infections have gone from 3,115 to 3,681, and leptospirosis cases have risen from 136 to 157 - a rise that has pushed the Brihanmumbai Municipal Corporation to inspect over 3,000 construction sites and carry out vector-control fogging in nearly 800,000 homes. Delhi is watching a similar pattern unfold, with 162 dengue cases, 42 malaria cases and nine chikungunya cases reported so far this year, and health authorities urging residents to act before the rains intensify further.

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Every year, the rains bring relief from the heat - and a fresh wave of infections that hospitals across the country brace for. Here are 10 monsoon diseases worth knowing about this season, and what doctors say actually works to prevent them.

Dengue Fever, The Season's Most Familiar Threat

Spread by Aedes mosquitoes that breed in clean, stagnant water, dengue commonly causes high fever, severe headache, muscle and joint pain, and skin rashes, and in severe cases can progress to dengue haemorrhagic fever. Nationally, the disease is arriving earlier each year - India had already recorded 6,927 dengue cases by the end of February 2026, a figure that has exceeded the entire January-May total of 2021 within just two months.

  • Empty coolers, buckets and flowerpots of standing water at least once a week
  • Use mosquito nets and repellents, especially between dawn and dusk
  • Watch for fever lasting more than three days, and get a platelet count checked

Malaria, Still A Monsoon Regular

malaria
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Malaria spreads through the Anopheles mosquito and follows a distinctive cyclical fever pattern, unlike dengue's constant high temperature. Mumbai alone has logged over 3,600 cases this year, a jump city health officials attribute directly to rainwater collecting in unlikely places - construction sites, tyres, terraces.

  • Cover all water storage containers
  • Seek testing promptly for cyclical fever with chills and sweating
  • Complete the full course of antimalarial treatment if prescribed, even after symptoms ease

Leptospirosis, The One Doctors Say Gets Missed

Leptospirosis spreads through contact with water or soil contaminated by animal urine - a real risk in waterlogged Indian streets. Complications can include bleeding from the lungs, meningitis and kidney failure, and the disease carries a fatality risk of around 7.5% if untreated. Its early symptoms mimic dengue and viral fever so closely that cases are frequently missed.

  • Avoid wading through floodwater; wear covered, waterproof footwear if you must
  • Wash feet and legs thoroughly with soap after contact with floodwater
  • Mention any floodwater exposure to your doctor if fever comes with severe calf pain

Chikungunya, The Joint-Pain Fever

Chikungunya
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Carried by the same Aedes mosquito as dengue, chikungunya causes fever alongside intense joint pain that can persist for weeks after the fever itself has gone. Delhi's civic body has already logged nine cases this year, alongside its dengue and malaria count.

  • Follow the same mosquito-breeding prevention steps used for dengue
  • Rest and stay hydrated; joint pain may need longer-term management
  • See a doctor if joint stiffness lingers well after the fever subsides

Typhoid Fever, Carried In Contaminated Water

Typhoid spreads through water or food contaminated with Salmonella typhi, and monsoon flooding makes contamination far more likely. It causes sustained high fever, weakness, stomach pain and, in some cases, a rash.

  • Drink only boiled or filtered water
  • Avoid street food and raw, unwashed produce during heavy rain
  • A blood culture is the most reliable way to confirm typhoid rather than relying on fever alone

Hepatitis A, The Liver Infection Floodwater Spreads

Hepatitis A
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Hepatitis A is a viral liver infection transmitted through contaminated food or water, causing jaundice, fatigue, nausea and abdominal discomfort, and it spreads more easily during monsoon because of floodwater contamination. India TV News

  • Prioritise food and water hygiene, especially with cut fruit and street vendors
  • Get vaccinated if you live in a flood-prone area
  • Watch for yellowing of the eyes or skin and seek care immediately

Cholera, The Diarrhoeal Disease That Moves Fast

Cholera is caused by drinking water or eating food contaminated with the bacterium Vibrio cholerae, and can cause severe watery diarrhoea and dehydration that, left untreated, can lead to death within hours. Poor sanitation during flooding is the main driver of outbreaks.

  • Stick to boiled, filtered or bottled water when sanitation is compromised
  • Keep oral rehydration salts at home and start rehydration at the first sign of diarrhoea
  • Seek emergency care if dehydration signs - sunken eyes, dry mouth, no urination - appear

Viral Fever, The Everyday Monsoon Illness

viral fever
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Sudden weather swings, getting drenched in rain, and sitting in wet clothes for hours all raise the odds of a viral infection. Dr Vikrant Shah, consulting physician, intensivist and infectious disease specialist at Zen Multispeciality Hospital, Chembur, notes that people getting drenched in rain or wearing wet clothes for extended periods raises their chances of getting a viral infection.

  • Change out of wet clothes as soon as possible
  • Rest and stay hydrated rather than pushing through a fever
  • Test for other infections if fever, joint pain and fatigue last beyond three days

Fungal Skin Infections, Humidity's Quiet Side Effect

Constant dampness and humidity keep skin from drying out properly, creating ideal conditions for fungal infections - particularly between toes, in skin folds, and on the scalp.

  • Keep skin dry; change out of damp clothes and socks promptly
  • Choose breathable, closed footwear over wet open sandals
  • Use an antifungal powder or cream at the first sign of itching or redness

Food Poisoning, The Risk On Every Plate

Contaminated water finds its way into cooking, and flies multiply around waterlogged areas - a combination that makes food poisoning peak during monsoon. Street food carries the highest risk, but home-cooked meals aren't immune if vegetables aren't washed properly.

  • Avoid street food and cut fruit sold in the open during heavy rain
  • Wash vegetables thoroughly and cook food fully before eating
  • Discard food that has been left out for more than a couple of hours in humid weather

Disclaimer: The information provided in this article is for general informational and educational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or a qualified healthcare provider with any questions you may have regarding a medical condition.

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