IAS Gyan

Daily News Analysis


28th July, 2023 Science and Technology

Copyright infringement not intended

Context: The Kerala State Health Department has issued an alert against scrub typhus.


  • Medical Officers stressed the need for rodent control, cleanliness and hygiene to prevent the disease. They said that people should avoid contact with animals that may carry chiggers, such as rats, rabbits, mice, and squirrels. They should also wear protective clothing and use mite repellents when entering shrubby areas. They should not dry clothes on the ground or grass, and they should clean their surroundings regularly.

Scrub typhus


  • Scrub typhus is a bacterial infection caused by Orientia tsutsugamushi, which is transmitted by the bite of infected chiggers (larval mites).
  • It is also known as tsutsugamushi disease or bush typhus.
  • Scrub typhus is endemic in the Asia-Pacific region, where it affects millions of people every year, especially in rural and agricultural areas.

Common Symptoms

  • Persistent high fever and Severe headaches are commonly experienced by individuals with scrub typhus.
  • Some people may develop a rash, which can be maculopapular (red spots), petechial (small red or purple spots), or a combination of both.
  • Enlarged and tender lymph nodes may be present, particularly in the region close to the site of the chigger bite.
  • An eschar, also known as a "tache noire," is a black scab or ulcer that forms at the site of the chigger bite. This is a characteristic feature of scrub typhus.
  • Muscle Pain and Joint Pain, Some patients may develop respiratory symptoms such as a dry cough.
  • In severe cases, scrub typhus can affect the central nervous system, leading to symptoms such as confusion, altered mental state, or even coma.

Impact of scrub typhus

  • If left untreated or not diagnosed early, scrub typhus can be fatal, with the mortality rate ranging from 1% to 30%, depending on factors like the strain of the bacteria and the availability of effective treatment.
  • Scrub typhus can result in substantial healthcare costs, including hospitalization, laboratory tests, and medications. Illness and hospitalization can lead to a loss of productivity for affected individuals and their families.
  • Scrub typhus can lead to outbreaks in certain regions, especially during the post-monsoon season when chigger populations are higher.
  • Misunderstanding and lack of awareness about scrub typhus may lead to stigma for affected individuals and their families.
  • Some individuals may experience lingering symptoms or complications even after recovering from acute scrub typhus, affecting their long-term health and quality of life.


  • The recommended treatment for scrub typhus is the antibiotic doxycycline, which can be used in persons of any age. Prompt diagnosis and early initiation of treatment are crucial to improving outcomes for patients with scrub typhus.
  • As of the current state of medical knowledge, there is no commercially available vaccine to prevent scrub typhus. Preventive measures primarily focus on avoiding exposure to chigger bites, such as wearing protective clothing, using insect repellents, and maintaining good hygiene in areas where the disease is endemic.
  • Raising awareness about scrub typhus and its transmission, along with implementing effective preventive strategies and timely treatment, can help reduce the burden of this potentially deadly disease in affected regions.

Steps taken by the government and other stakeholders

  • Strengthening the surveillance and reporting system for scrub typhus and other vector-borne diseases.
  • Enhancing the laboratory capacity and quality assurance for the detection and confirmation of scrub typhus cases.
  • Providing guidelines and training for the clinical management and prevention of scrub typhus.
  • Increasing the availability and accessibility of effective antibiotics such as doxycycline and azithromycin for the treatment of scrub typhus.
  • Promoting the use of personal protective measures such as wearing long-sleeved clothes, applying insect repellents, and avoiding contact with vegetation where chiggers are present.
  • Conducting research and development on novel diagnostics, vaccines, and therapeutics for scrub typhus.

Challenges and gaps that need to be addressed

  • Improving the awareness and knowledge of scrub typhus among healthcare providers and the general population.
  • Expanding the coverage and quality of surveillance and reporting systems for scrub typhus and other vector-borne diseases.
  • Developing more sensitive, specific, rapid, and affordable diagnostic tests for scrub typhus.
  • Evaluating the efficacy and safety of existing and new antibiotics for scrub typhus.
  • Identifying the risk factors and determinants of scrub typhus transmission and distribution.
  • Implementing integrated vector management strategies to reduce the exposure to chiggers and other vectors.
  • Collaborating with regional and global partners to share best practices and experiences on scrub typhus prevention and control.


  • Scrub typhus poses a significant public health challenge in India, where it has been reported in various states and regions. The disease has been associated with outbreaks of acute febrile illness in different parts of the country, especially during the post-monsoon season. The diagnosis of scrub typhus is often delayed or missed due to its nonspecific clinical presentation and lack of awareness among healthcare providers and the general population. Moreover, the disease is often confused with other common febrile illnesses such as malaria, dengue, leptospirosis, and typhoid. Scrub typhus deserves more attention and action from all stakeholders. By addressing the challenges and gaps, India can achieve its goal of eliminating scrub typhus as a public health problem in the near future.


Q. How is scrub typhus transmitted to humans?

A) Through the bites of infected mosquitoes

B) Through contaminated food and water

C) Through direct contact with infected individuals

D) Through bites of infected chiggers (larval mites)

Answer: D

Explanation: Scrub typhus is transmitted to humans through the bites of infected chiggers, which are the larval stage of trombiculid mites. These mites are commonly found in areas with dense vegetation, such as forests, grasslands, and scrublands. When the infected chigger bites a human, it transfers the Orientia tsutsugamushi bacterium, which causes scrub typhus. It is important to take preventive measures, such as wearing protective clothing and using insect repellents, to reduce the risk of getting bitten by infected chiggers in areas where scrub typhus is prevalent.