As winter gives way to summer, cases of fever, water-borne disease and respiratory illness are rising in major hospitals in the Kathmandu Valley. Also, air pollution has spiked in Kathmandu as the city has ranked as the world’s most polluted consistently for the past few days.

Doctors say the exact cause of the upsurge in the cases of fever is yet to be established, but they attribute the rise in respiratory illnesses and waterborne diseases to increasing air pollution and contaminated food and water.

“Compared to the previous year, cases of respiratory illnesses have risen this year,” said Dr Raju Pangeni, a pulmonary and critical care physician at HAMS Hospital. “Cases of fever and cough have also started rising. Patients are suffering from prolonged coughs that take months to cure.”

With rising temperatures—both minimum and maximum—cases of seasonal ailments including viral fever, cough, flu, and waterborne infections are rising throughout the country. Every year, during seasonal transitions, the number of patients with high-grade fevers, waterborne and food-borne diseases, and respiratory illnesses rises. Doctors warn that people should not be complacent about these ailments as those with underlying health conditions are at higher risk of getting severe.

“The number of severe patients suffering from respiratory illness requiring intensive care has increased in our hospital,” said Pangeni. “So let's not take this lightly. Think about your dear ones with compromised immunity before ignoring the risks. Follow the basic precautions taught during the coronavirus pandemic.”

Doctors at Sukraraj Tropical and Infectious Disease Hospital and Patan Hospital said they expect a significant rise in cases of viral fever, and water-borne and food-borne diseases in the coming days.

“Around 700 patients seek outpatient care at our hospital these days,” said Dr Yuba Nidhi Basaula, the director at the hospital. “The number has doubled compared to other times.”

According to the hospital administration, earlier, the number of patients seeking vaccination for dog bites used to be more than the number of patients seeking care for other ailments. But, in recent days, more people are visiting the hospital with cases of fever, skin diseases, cough, flu, snake bites, dengue, and malaria.

“Around 40 patients with seasonal flu and fever visit the hospital every day. Those with skin diseases number around 150. And about a dozen patients of diarrheal ailments seek treatment in the hospital’s emergency and outpatient departments daily,” said Basaula. “This trend indicates the looming epidemic season.”

Besides these ailments, chronic obstructive pulmonary disease, pneumonia, and jaundice are also prevalent, according to hospital records.

The hospital administration said that a patient suffering from high fever and rashes was found infected with dengue virus a few days ago.

Dengue is a mosquito-borne disease transmitted by the female Aedes aegypti and Aedes albopictus mosquitoes. The same vector also transmits chikungunya, yellow fever, and Zika, according to the World Health Organisation.

At least 15 died, and 41,865 others were infected by the deadly virus in 2024.

“We have anticipated a surge in seasonal ailments in coming days,” said Dr Samita Panta Acharya, medical director at the Patan Hospital. “Patients suffering from fever, cough and flu have been seeking care in our hospital.”

“Cases of seasonal diseases have risen sharply in Humla in recent days,” said Dr Dev Gajamer of the District Hospital Humla over the phone from Simkot, headquarters of the district, earlier this week. “Over 80 patients visit the outpatients department of the hospital every day.”

The Epidemiology and Disease Control Division said that it is aware of the risk of an outbreak of seasonal diseases in the coming days and has asked agencies concerned to report the surge of any ailments.

“We have stepped up surveillance and are aware of risks of possible outbreaks,” said Dr Mukesh Poudel, chief of the Epidemiology and Outbreak Management Section at the division. “We plan to conduct regular testing of drinking water samples to examine the quality of water used by the general public.”

Contaminated drinking water, rising pollution, food poisoning, and lack of awareness have been blamed for the increasing cases of seasonal diseases.

Doctors say due to poor sanitation and hygiene conditions, the country is highly vulnerable to water-borne diseases, including diarrhoea, dysentery, typhoid, hepatitis, and cholera, with thousands of people falling sick every year.

They say initiating awareness drives and ensuring safe drinking water are the only ways to save people from water-borne diseases, including cholera. A combination of careful surveys, provision of safe drinking water, good sanitation and hygiene standards, social mobilisation, and treatment are required to contain the spread of infection, they added.