Prevalence and risk factors for scrub typhus in South India.
To determine the prevalence and risk factors of scrub typhus in Tamil Nadu, South India.



We performed a clustered seroprevalence study of the areas around Vellore. All participants completed a risk factor survey, with seropositive and seronegative participants acting as cases and controls, respectively, in a risk factor analysis. After univariate analysis, variables found to be significant underwent multivariate analysis.



Of 721 people participating in this study, 31.8% tested seropositive. By univariate analysis, after accounting for clustering, having a house that was clustered with other houses, having a fewer rooms in a house, having fewer people living in a household, defecating outside, female sex, age >60 years, shorter height, lower weight, smaller body mass index and smaller mid-upper arm circumference were found to be significantly associated with seropositivity. After multivariate regression modelling, living in a house clustered with other houses, female sex and age >60 years were significantly associated with scrub typhus exposure.



Overall, scrub typhus is much more common than previously thought. Previously described individual environmental and habitual risk factors seem to have less importance in South India, perhaps because of the overall scrub typhus-conducive nature of the environment in this region.
Spectrum Health Center for Integrative Medicine, Grand Rapids, MI, USA.|Tufts Medical Center/Tufts University, Boston, MA, USA.
Paul
P
Trowbridge
Christian Medical College, Vellore, India.
Divya
D
P
Christian Medical College, Vellore, India.
Prasanna S
PS
Premkumar
Christian Medical College, Vellore, India.
George M
GM
Varghese
D000367:Age Factors; D049628:Body Size; D003672:Defecation; D004777:Environment; D005191:Family Characteristics; D005260:Female; D006798:Housing; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012285:Orientia tsutsugamushi; D015995:Prevalence; D012307:Risk Factors; D012499:Sanitation; D012612:Scrub Typhus / Q000453:epidemiology* / Q000209:etiology / Q000382:microbiology; D016036:Seroepidemiologic Studies; D012737:Sex Factors
South India; facteurs de risque; factores de riesgo; prevalence; prevalencia; prévalence; risk factors; scrub typhus; sud de l'Inde; sur de la India; tifus exantémico; typhus des broussailles