Is Delhi an Emerging Scrub Typhus Hotspot? An Entomological and Zoonotic Exploration of a Scrub Typhus Outbreak
Background: Scrub typhus is an emerging public health challenge in India with increasing evidence of its activity being reported from all over the country. An outbreak of scrub typhus was reported from an area of South West Delhi, India hitherto not known for scrub typhus activity which prompted this zoonotic and entomological investigation.
Methods: Zoonotic and entomological investigations were undertaken in five residential areas of South West Delhi, India located in the vicinity of the reporting hospital to determine the rodent hosts, vector mite diversity, and rickettsial activity in rodents. The rickettsial activity was ascertained using Weil-Felix test.
Results: Palam area of Delhi, India is a hotspot of scrub typhus with evidence of tick and endemic typhus activity as well. This study reports the presence of known vectors of scrub typhus viz. Leptotrombidium deliense and Schoengastiella ligula, besides enriching the database of mite fauna of Delhi with an addition of a total of five new records, three of Leptotrombidium - vietzi, bhattipadense, fulmentum, and two records of Ascoschoengastia indica and Walchia lupella.
Conclusion: The study reports Delhi as a scrub typhus hotspot. In Delhi, Palam was the most affected and had the highest number of cases and deaths, presence of the vectors of scrub typhus and evidence of tick and endemic typhus activity amongst rodents. The mite database of Delhi has been updated with the addition of five new trombiculid mite records.
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Tilak R, Mukherjee R, Malik A, Bhatti VK, Pandya K, Wankhade UB. Is Delhi an Emerging Scrub Typhus Hotspot? An Entomological and Zoonotic Exploration of a Scrub Typhus Outbreak. J Commun Dis. 2022;54(1):100-106.
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