Volume 69, Issue 5
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Extensive sampling of small mammals was conducted in eight provinces of Thailand between September 9, 1992 and April 29, 2001. A total of 3,498 specimens representing 22 species were collected. Eighty-eight percent (3,089 of 3,498) of the animals were collected from a region in Chiangrai Province, which is commonly recognized as endemic for human scrub typhus. Blood and tissue samples from each animal were tested for the presence of , the etiologic agent of scrub typhus. The predominant species collected were (53%, n = 1,863), (18%, n = 638), (16%, n = 564), and (4%, n = 146). was detected in 10 of the 22 species of mammals that included (25% infected, 1 of 4), (23%, 419 of 1,855), (22%, 5 of 23), (22%, 2 of 9), (13%, 82 of 638), (9%, 52 of 564), (8%, 1 of 12), (3%, 1 of 30), (1%, 2 of 146), and (2%, 1 of 49). Infected animals were found in Chiangrai (18% infected, 563 of 3,084), Bangkok (11%, 1 of 9), Sukothai (3%, 1 of 30), and Nonthaburi (1%, 1 of 69) Provinces. The implications towards scrub typhus maintenance and transmission are discussed.


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  • Received : 20 Apr 2002
  • Accepted : 03 Mar 2003

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