Do You Know Scrub Typhus?

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“5 peoples died within 20 days at Government Medical College & Hospital at Nagpur” Times of India on 26 august 2018. Unexpected searches started everywhere after reading the present newspaper headline. The reason was Scrub typhus. The type of disease for which no another word exists in local language, Marathi. For many people it’s kind of unknown disease, even for the many academicians. What is the cause? Is the disease limited to Nagpur? or spread all over India; more importantly is there any medicine or preventive measure available? Biggest question was how the disease suddenly evokes with number of cases, mere within the months of august and still continues. In this article, we have trying to find estimated reasons for the outbreak of the disease ‘Scrub Typhus’.

PC: Author


Scrub typhus was earlier reported in the capital ‘Delhi’. Safdarjung hospital; one of the biggest hospital in Delhi had 11 cases of scrub typhus within first 9 days of September; whereas it iterated as 15 in the month of august. AIIMS medical hospital in Delhi has recorded cases in month of august and September but did not confirm the number. Sir Gangaram hospital has reported 10 case in august. There are other several hospitals in Delhi who reported the cases of Scrub typhus. Back in 2003-04 and in 2007 outbreaks were reported from Himachal Pradesh, Sikkim and West Bengal.


Notably, present scenario has been changed than ever before. Before, patients were checked rarely either for the presence of any rickettsial disease or checked only if any case came with unknown cause of fever; lasting for exceptionally longer period of time along with prominent marks of ‘Eschars (cigarette butt like black spot on the place of bites from mite)’ on the inner body parts. But now, on the first day itself; patients are being screened for rickettsia at most of the hospitals in India. Present observation is supported by a 2012-study from the National Centre of Disease Control, which showed that 8.2% of the patients with fever of unknown origins tested positive for rickettsial diseases. However, whenever a ‘rickettsial disease’ was considered as a differential diagnosis, the seropositivity increased to 33.3% (Mittal et al., 2012).


In the history

For the first time in 2012; disease has been clinically recorded at Nagpur hospital. It was said there were no special clinical difference compared with other disease for differential diagnosis except the Escher on body parts. This special sign of disease may be present in about 40-50% of patients. That is why the present outbreaks are considered as re-emergence of Scrub typhus in India with epidemics at several places.


The kind of disease?

It is a non-contagious disease that does not transmit through physical contact. It caused by a rickettsial infectious agent Orientiasia tsutsugamushi, which was noticed first time in Japan. The infectious organism requires a vector for transmission from one person to other. Vector agents like mites, ticks, flies and lice are the responsible one. Among those ‘mites-larvae’ are playing a major role in transmission of this disease to human as compared to other. The disease is more common in tropical areas where cases are found all over the year; but, it is seasonal in temperate areas.


Clinical manifestations?

The symptoms of scrub typhus are high fever, skin rashes, respiratory problems, red eyes and unconsciousness with a prominent body mark of eschars. Some patients also develop joint pain, which is characteristic of chikungunya and dengue. The infection further lead to respiratory distress, inflammation of brain and lungs, kidney failure and then multi-organ failure ultimately leads to death.
















PC: Author


Epidemic area?

Scrub typhus has spread over more than half of Asia, Russia and Australian subcontinents covering wide areas of 13 million sq. kilometers. In India, it has spread from Shivalik ranges from Kashmir to Eastern Ghats of Assam, covering the Vindhyachal and Satpuda ranges of the central part of India. Areas of deforestation, river banks, and open grassland provide optimal conditions for the infected mites to thrive. These small geographic regions possess high-risk for human and called as scrub typhus islands. Though the disease occurs throughout the year in tropics and seasonal in temperate areas; the infection proliferates in rainy season mainly through mite’s larva called ‘chiggers’ as they are blood feeders. Rodents harbor mites in wetter months of year or in similar environment. The vectors of scrub typhus Leptotrombidium deliense and Leptotrombidiu makamushi are present in most of the countries and are native to certain regions in India. These vectors are found in rainy forests, bushy deserts and even in Himalayan terrains. These are mite islands where disease is constantly ought to be present.


Reason for sudden outbreak

Due to ecological changes such as deforestation and diversion of land use wild rodents could readily access to the urban areas. Rodents naturally harbor the mites. Mites could travel long distances easily as they remain attached to body surface of rodents coming nearer to human locality. The mites as per life cycle pattern are molding to larval stage found on body surfaces of rodents during rainy season. Due to heavy rainfall in different areas in India during last months of summer, mites successively transmit the disease to human locality. Historically, yet the disease remains sporadic in India. So, no immediate confirmatory and differential diagnostic tests facilities were present in the hospitals; patients remain misdiagnosed and due course the disease might have been proliferated resulted in reporting of more number of cases to hospitals in short period.


Hill and village connection of the disease?

The disease was thought to be found in the hilly regions because the areas have the vegetation to support the proliferation of the vectors, i.e. tics and mites. Presently, the more cases are being detected in the plains.The reason explained was that more peoples are getting tested. More than that changing climate due to deforestation is responsible to spreading of such cases in plain areas.

The disease is not limited to the particular district or area or a state; reports were recovered from almost all over India. In the year of 2018 itself, the Scrub typhus cases reported from several sectors of North Delhi, Vidarbha region of Maharashtrabetween the months of January to July. Also, in recent years scrub typhus has rapidly remerged to become the major cause of AFI (accidental fever with infection) in many parts of India, especially during the monsoon and post monsoon seasons. Of the 29 states in India, 23 have reported the presence of scrub typhus.

PC: Author


Difficulty in diagnosis and prognosis?

Due to sporadic nature of the disease; even government hospitals won’t have the diagnostic facility for the scrub typhus. All variants of rickettsial diseases have to be screened for confirmative diagnosis. Although; applied test should be highly sensitive and specific. Hence; mostly the patients with proper history and symptoms only were happened to get tested for Srcub typhus just after confirmed negative for Dengue and Chickengunya.


If the case has been diagnosed at the early stage then even simple antibiotics treatment will work over it successfully. Early presentation of disease with duration of fever of less than 10 days has better prognosis when compared with fever duration of greater than 12 days. If disease cause remains undiagnosed for longer period or patients proceed in a later stage with multi-organ failure, then it becomes very difficult to treat.


Available treatment?

Disease can be treated with antibiotic ‘Doxycycline’; the only drug of choice in early stages. Hence; doctors should be aware enough for diagnosis of disease and patients should be enough careful for visiting the doctors at early stage itself. Early diagnosis and institution of specific treatment will reduce morbidity and mortality from infectious disease of Scrub typhus.


Safety and precaution

The rickettsial infection can be checked by increasing awareness in local public and professionals by updating its diagnostic facility. Community is in urgent demand of rapid diagnostic assays at every possible hospital/lab and coupled with implementation of appropriate treatment protocol to control such acute febrile cases at community level to mitigate the present scenario.


Conclusion

Deforestation, shrinkage of wildlife habitat, improper drainage system in urban area are some of the main cause of re-emergent of diseases like scrub typhus. Provision of rapid diagnostic facility to the government hospitals is essential to reduce death toll and to check outbreak. Public health awareness and implementation of one health program is need of time. Cleanliness and personal hygiene are the key.


Authors

College of Veterinary and Animal Sciences, Udgir-413517, M.S., India


Reference:

Mittal, V., Gupta, N., Bhattacharya, D., Kumar, K., Ichhpujani, R.L., Singh, S., Chhabra, M. and Rana, U.V.S., 2012. Serological evidence of rickettsial infections in Delhi. The Indian journal of medical research, 135(4), p.538.