• A study conducted by researchers from Christian Medical College (CMC) Vellore, in collaboration with the London School of Hygiene & Tropical Medicine (LSHTM), has revealed that rural communities are at a high risk of scrub typhus.

• The findings, published in the New England Journal of Medicine, underscore the urgent need for increased awareness and improved diagnostic capabilities in rural areas.

Scrub Typhus

• Scrub typhus is a potentially life-threatening infection caused by the bacterium Orientia tsutsugamushi, which belongs to the rickettsia family. 

It is spread to humans through the bite of infected larval mites or chiggers.

• Rural communities, particularly those engaged in farming or outdoor activities, are at higher risk due to increased exposure to chiggers.

• Rickettsial diseases have been documented in India since the 1930s with reports of scrub typhus from Kumaon region, in soldiers during World War II in Assam, scrub and murine typhus from Jabalpur area in Madhya Pradesh and murine typhus from Kashmir.

• Surveillance in animals and humans in different parts of India has documented significant levels of exposure to infections.

Symptoms:

• Symptoms include fever, headache, body aches, and a rash, typically appearing around 10 days after infection.

• A blackened sore often develops at the site of the chigger bite, aiding in diagnosis.

• If untreated, scrub typhus can lead to severe complications such as acute respiratory distress syndrome (ARDS), shock, meningitis, and kidney failure, which can be fatal.

Treatment and Prevention:

• The infection can be treated with antibiotics like doxycycline and azithromycin.

• However, there is currently no vaccine available for prevention.

Key findings of the study:

• The study, conducted over two years, examined 32,000 people in rural areas of Tamil Nadu.

• It found that nearly 10 per cent of the population was infected with scrub typhus annually.

• While most infections were asymptomatic, 8-15 per cent of those infected developed fever severe enough to require hospitalisation and intensive care.

• Scrub typhus was identified as the second most significant cause of fever-related hospitalizations after COVID-19, accounting for nearly 30 per cent of such cases.

• Despite its prevalence, scrub typhus is often overlooked as a potential cause of fever due to limited diagnostic capabilities in rural areas.

• During the study, five deaths were reported due to scrub typhus-related complications.

• Researchers noted that under-reporting of fever cases posed a limitation to the study.

(The author is a trainer for Civil Services aspirants.)