Epidemiology & risk factors of scrub typhus in south India.

Background & objectives: Scrub typhus is a major public health threat in South and Southeastern Asian countries including India. Understanding local patterns of disease and factors that place individuals at risk is pivotal to future preventive measures against scrub typhus. The primary aim of this study was to identify specific epidemiological and geographical factors associated with an increased risk of developing scrub typhus in this region. Methods: We mapped 709 patients from Tamil Nadu, Andhra Pradesh and Telangana who were admitted to the Christian Medical College (CMC) Hospital, Vellore, Tamil Nadu, India, for the period 2006-2011, assessed seasonality using monthly counts of scrub typhus cases, and conducted a case-control study among a subset of patients residing in Vellore. Results: The geographic distribution of cases at CMC Hospital clusters around the Tamil Nadu-Andhra Pradesh border. However, distinct hotspots clearly exist distal to this area, near Madurai and the coast in Tamil Nadu, and in the Northeast of Andhra Pradesh. Seasonally, the highest numbers of cases were observed in the cooler months of the year, i.e. September to January. In the case-control analysis, cases were more likely to be agricultural laborers (OR 1.79, 95% CI 1.01 - 3.15), not wear a shirt at home (OR 4.23, 95% CI 1.12 - 16.3), live in houses adjacent to bushes or shrubs (OR 1.95, 95% CI 1.08 - 3.53), and live in a single room home (OR 1.75, 95% CI 1.02 - 3.01). On binary logistic regression, the first three of these variables were statistically significant. Interpretation & conclusions: With the growing number of cases detected in India, scrub typhus is fast emerging as a public health threat and further research to protect the population from this deadly infection is essential. Health education campaigns focusing on the agricultural workers of Southern India, especially during the cooler months of the year, can serve as an important public health measure to control infection.

Awareness and knowledge of diabetes in Chennai--the Chennai Urban Rural Epidemiology Study [CURES-9]

BACKGROUND AND AIM: There are virtually no epidemiological studies from India assessing the level of awareness of diabetes in a whole population. The aim of the present study was to assess the awareness of diabetes in an urban south Indian population in Chennai. METHODS: The Chennai Urban Rural Epidemiology Study (CURES) is an ongoing population based study conducted using a systematic sampling method on a representative population (aged > or = 20 years - 26001 individuals) of Chennai [formerly Madras], the largest city in Southern India. A structured questionnaire was used to obtain information related to demography, education and medical history. The questionnaire included five questions on diabetes awareness. RESULTS: Of the total 26,001 individuals, only 75.5% (19642/26001) of the whole population reported that they knew about a condition called diabetes or conversely nearly 25% of the Chennai population was unaware of a condition called diabetes. 60.2% (15656/26001) of all participants and 76.7% (1173/1529) of the self reported diabetic subjects knew that the prevalence of diabetes was increasing in India. Only 22.2% (5764/ 26001) of the whole population and 41.0% (627/1529) of the known diabetic subjects were aware that diabetes could be prevented. Knowledge of the role of obesity and physical inactivity in producing diabetes was very low, with only 11.9% (3083/26001) of study subjects reporting these as risk factors for diabetes. Only 19.0% (4951/26001) of whole population knew that diabetes could cause complications. Even among the self reported diabetic subjects, only 40.6% (621/1529) were aware that diabetes could produce some complications. CONCLUSION: Awareness and knowledge regarding diabetes is still grossly inadequate in India. Massive diabetes education programmes are urgently needed both in urban and rural India.

Validation of body fat measurement by skinfolds and two bioelectric impedance methods with DEXA--the Chennai Urban Rural Epidemiology Study [CURES-3].

BACKGROUND AND OBJECTIVE: Although Asian Indians have been shown to have increased body fat compared to Europeans, there have been very few studies in Asian Indians validating the various methods available for body fat measurement. The aim of this study was to test the validity of body fat measured by two commercial impedance analyzers (leg-to-leg and hand-held) as well as by skinfolds with Dual Energy X-ray Absorptiometry (DEXA) as the reference method in a population based study in southern India. METHODS: Body fat percentage (BF%) was measured in 162 South Indian urban men (n=76) and women (n=86) randomly selected from the "Chennai Urban Rural Epidemiology Study" (CURES), an ongoing population based study of a representative population of Chennai. The mean age of the subjects was 45.1 +/- 9.0 years and the body mass index ranged from 16.4 - 34.4 kg/m2. Percentage body fat was measured using DEXA, segmental impedance (leg-to-leg: BF%IMP-LEG; and hand-held BF%IMP-HAND) using the manufacturer's software and skinfolds using the prediction equation from the literature (BF%SKFD). RESULTS: Body fat (%) determined by the leg-to-leg method (BF%IMP-LEG 35.10 +/- 7.26) and the skinfolds (BF%SKFD 35.77 +/- 6.06) did not differ significantly from the reference method DEXA (BF%DEXA 35.82 +/- 8.33), but the hand-held impedance method (BF%IMP-HAND 31.38 +/- 6.24) showed significant difference (p < 0.001). The bias for estimation of body fat (%) for the bioimpedance leg-to-leg, hand-held and skinfolds were 0.73 +/- 5.70, 4.45 +/- 4.83 and 0.06 +/- 5.86 respectively. All the three methods showed a fairly good correlation with DEXA (BF%IMP-LEG: r = 0.741, p<0.001; BF%IMP-HAND: r = 0.817, p< 0.001; BF%SKFD: r 0.710, p< 0.001). CONCLUSION: The study shows that in urban south Indians, measurement of body fat by the leg-to-leg impedance and the skinfold method have better agreement (lower bias) with DEXA than the hand-held impedance. However, all three methods (skinfolds, the leg-to-leg bioelectric impedance and hand-held impedance) show a fairly good correlation with DEXA.