Spatial analysis of scrub typhus infection and its association with environmental and socioeconomic factors in Taiwan

Chi-Chien Kuo, Jing Lun Huang, Chia Ying Ko, Pei Fen Lee, Hsi Chieh Wang

Research output: Contribution to journalArticle

41 Citations (Scopus)

Abstract

We analyzed the spatial distribution of human cases of scrub typhus on the main island of Taiwan from 2003 to 2008 and implemented an island-wide survey of scrub typhus vectors (trombiculid chiggers) in 2007 and 2008. The standardized incidence rate 'SIR' incorporating inter-district variations in population, gender and age was correlated with environmental and socioeconomic variables. Higher incidence and SIR rates were clustered in the less developed, mountainous regions of central and eastern Taiwan. Higher SIRs were also associated with a higher proportion of dry-field farmers in the population, a higher normalized difference vegetation index (NDVI) and lower mean annual temperature, but was not associated with rainfall. Small mammal hosts in high-SIR districts harbored more chiggers and had higher rates of seropositivity against Orientia tsutsugamushi Hyashi, the etiologic agent of scrub typhus, compared to low-SIR districts. The concurrence of a higher proportion of dry-field farmers and higher NDVI has likely led to the clustering of scrub typhus in the mountainous regions of Taiwan. Further individual-level study of the risk factors associated with scrub typhus, and a better understanding of the effect of environmental factors on chigger abundance, should help to prevent scrub typhus in Taiwan.

Original languageEnglish
Pages (from-to)52-58
Number of pages7
JournalActa Tropica
Volume120
Issue number1-2
DOIs
Publication statusPublished - 2011 Oct 1

Fingerprint

scrub typhus
Scrub Typhus
Spatial Analysis
socioeconomic factors
Taiwan
Trombiculidae
chiggers
environmental factors
Infection
infection
Islands
Orientia tsutsugamushi
farmers
Incidence
small mammals
angle of incidence
seroprevalence
Population
Cluster Analysis
Mammals

Keywords

  • Environment
  • Orientia tsutsugamushi
  • Scrub typhus
  • Socioeconomic factors
  • Taiwan
  • Trombiculidae

ASJC Scopus subject areas

  • Parasitology
  • Infectious Diseases

Cite this

Spatial analysis of scrub typhus infection and its association with environmental and socioeconomic factors in Taiwan. / Kuo, Chi-Chien; Huang, Jing Lun; Ko, Chia Ying; Lee, Pei Fen; Wang, Hsi Chieh.

In: Acta Tropica, Vol. 120, No. 1-2, 01.10.2011, p. 52-58.

Research output: Contribution to journalArticle

Kuo, Chi-Chien ; Huang, Jing Lun ; Ko, Chia Ying ; Lee, Pei Fen ; Wang, Hsi Chieh. / Spatial analysis of scrub typhus infection and its association with environmental and socioeconomic factors in Taiwan. In: Acta Tropica. 2011 ; Vol. 120, No. 1-2. pp. 52-58.
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