Over 3,500 people across the country have been infected with scrub typhus since mid-July, the start of this fiscal year.

Officials at the Epidemiology and Disease Control Division say they expect more cases in the coming days as the disease typically peaks in September.

“Like in previous years, hundreds of people have also been infected with scrub typhus this year,” said Dr Gokarna Dahal, chief of vector Control Section at the division. “More people can get infected in the coming days, as the peak season is still ahead.”

Scrub typhus, or bush typhus, is an infectious disease caused by the parasite Orientia tsutsugamushi, a mite-borne bacterium. It spreads in humans when bitten by infected chiggers (larval mites) found in mice.

Until a few years ago, it was believed that people residing in rural areas or those working in grasslands or fields were at high risk. However, urban populations are also now being affected by the disease.

“Over 100 people from Hetauda Sub-metropolitan city have been infected from Scrub typhus this year,” said Krishna Bahadur Major, chief of the Health Office, Makawanpur. “Although more cases are reported in villages, urban areas are not immune, with several positive cases emerging there as well.”

Doctors point out high fever, headache, abdominal pain, backache, joint and muscle pain, red rash, nausea and vomiting as some of the symptoms of scrub typhus infection. Patients with severe illness may develop bleeding which could lead to organ failure. The infection can lead to respiratory distress, inflation of brain, lungs, kidney failure and then multi-organ failure. If not treated immediately, it could be fatal.

Nepal saw a surge in scrub typhus cases after the calamitous 2015 earthquakes that killed nearly 9,000 persons across the country.

Three months after the quakes, the BP Koirala Institute of Health Sciences, Dharan, alerted the Epidemiology and Disease Control Division about six children with unusual fevers and severe respiratory problems.

Serum samples were collected for subsequent tests in Kathmandu and Bangkok, which confirmed a scrub typhus outbreak. By then, four children had already died in the course of the treatment. By the end of the year, 101 cases were confirmed in 16 districts, and four more people succumbed to the disease.

The magnitude of the outbreak escalated in 2016 when 831 cases of scrub typhus were reported in 47 districts, and 14 people died by the end of that year.

According to the Ministry of Health and Population data, more than 1,026 people were infected with the disease in 2020. Their number increased to 1,999 in 2021, and it rose to more than 2,900 in 2022.

In 2023, over 5,000 people were infected with the deadly disease.

Doctors say the risk of severity and fatality can be minimised if the patients are diagnosed and treated early, they say.

Ordinary antibiotics, such as doxycycline and azithromycin, which are on the essential drugs list supplied by the government to health facilities across the country for free distribution, can cure the disease.

However, what is concerning is that many health workers, including doctors, lack sufficient knowledge about diagnosing scrub typhus. Many health facilities also lack reagents to carry out tests for the disease.

Doctors can diagnose the disease based on the symptoms, but the risk of misdiagnosis is high, as scrub typhus symptoms are similar to those of other illnesses.

They warn that waiting for lab results before starting treatment could be dangerous. It can take about a week to get lab results, and by that time, if the patient is not treated can fall into a coma and suffer multi-organ failure.