Clinical relevance of cagA and vacA and association with mucosal findings in Helicobacter pylori-infected individuals from Chennai, South India

Helicobacter pylori is associated with a spectrum of severe gastrointestinal conditions. In this study, an attempt was made to correlate endoscopic mucosal patterns with H. pylori infection and examine the pathogenic potential of the strains. Among the 147 dyspeptic individuals studied, 42.2% were H. pylori infected. Association of H. pylori with type 3 and 4 mucosal patterns (P = 0.001) and intestinal metaplasia (P = 0.012) was seen. vacA was associated with histological (P = 0.014) and endoscopy findings (P = 0.009). Association of mucosal patterns with H. pylori infection could be useful for clinicians to decide on the need for eradication therapy.

Interpretation of Rotavirus-positivity Patterns Across India.

bjective: To analyze variation in rotavirus-positivity using simple alternative statistical measures. Methods: Hospital-based rotavirus surveillance among children admitted with acute gastroenteritis between 2005 and 2009. Prevalence, adjusted proportions and symmetrized index were calculated. Results: Rotavirus prevalence was 40% (range 37% - 44%). Adjusted proportion analysis revealed higher level of deviation from annual prevalence in seasons (December – February and September – November); age groups (<12 months and 12-23 months) and regions (East and South). Analysis of symmetrized index revealed higher estimates of variation in all years, except in 2006. Conclusion: Proposed statistical measures are useful as refined measures to study extent of disease spread in surveillance programmes, aiding evaluation of the load and pattern of disease burden in different regions over time.

Profile and Trends of Rotavirus Gastroenteritis in Under-five Children in India (2012-2014): Preliminary Report of the Indian National Rotavirus Surveillance Network.

Objective: To estimate the burden of rotavirus-associated gastroenteritis in India. Methods: Hospital-based surveillance network was established, with clinical evaluation and laboratory testing for rotavirus among children aged below 5 years hospitalized with acute gastroenteritis. Results: Between September 2012 and December 2014, stool samples from 10207 children were tested and rotavirus was detected in 39.6% of cases. Infections were more commonly seen among younger children (<2 years). Detection rates were higher during cooler months of September – February. Among rotavirus infected-children, 64.0% had severe or very severe disease. G1P[8] was the predominant rotavirus genotype (62.7%) observed during the surveillance period. Conclusions: Surveillance data highlights the high rotavirus disease burden and emphasizes the need for close monitoring to reduce morbidity and mortality associated with rotavirus gastroenteritis in India.

Expanded Indian National Rotavirus Surveillance Network in the Context of Rotavirus Vaccine Introduction.

Objective: To extend a nation-wide rotavirus surveillance network in India, and to generate geographically representative data on rotaviral disease burden and prevalent strains. Design: Hospital-based surveillance. Setting: A comprehensive multicenter, multi-state hospital based surveillance network was established in a phased manner involving 28 hospital sites across 17 states and two union territories in India. Patients: Cases of acute diarrhea among children below 5 years of age admitted in the participating hospitals. Results: During the 28-month study period between September 2012 and December 2014, 11898 children were enrolled and stool samples from 10207 children admitted with acute diarrhea were tested; 39.6% were positive for rotavirus. Highest positivity was seen in Tanda (60.4%) and Bhubaneswar (60.4%) followed by Midnapore (59.5%). Rotavirus infection was seen more among children aged below 2 years with highest (46.7%) positivity in the age group of 12-23 months. Cooler months of September – February accounted for most of the rotavirus-associated gastroenteritis, with highest prevalence seen during December – February (56.4%). 64% of rotavirus-infected children had severe to very severe disease. G1 P[8] was the predominant rotavirus strain (62.7%) during the surveillance period. Conclusions: The surveillance data highlights the high rotaviral disease burden in India. The network will continue to be a platform for monitoring the impact of the vaccine.

Lot quality assurance sampling for monitoring immunization coverage in Madras City.

OBJECTIVE: To explore the usefulness of Lot Quality Assurance Sampling (LQAS) to identify divisions in a city that had immunization coverage levels of 80% for any of the four EPI vaccines. METHODS: Only 43 divisions were considered for the study, the stratification factor being the death rate. The hypothesis that 80% coverage is 'unacceptable' was stipulated. Critical value (the number of unimmunized children) was chosen as 3. A simple random sample of 36 children in the age-group 12-23 months was taken from each selected division. Since sampling frames of children were not available, a simple random sample of 36 households was selected. Immunization status of each child was assessed by interviewing the child's mother/guardian. If the number of unimmunized children exceeded 3, then the division was regarded having coverage level 80% and rejected. RESULTS: The coverage was classified as unacceptable(i. e., below 80%) in 19 divisions for Polio and DPT vaccines, in 26 divisions for Measles vaccine and in 4 divisions for BCG vaccine. The average time spent for undertaking the LQAS survey was 6 man-days per division. CONCLUSION: This study demonstrated the utility of the LQAS technique in identifying 'unsatisfactory' pockets in Madras City, when the overall coverage was satisfactory. The technique will have greater application with an increase in the number of large units (cities/districts) having an overall coverage of 90% or more.

A concurrent comparison of a WHO-recommended 30-cluster survey and a modified version of it under Indian conditions in the estimation of immunization coverages.

A concurrent comparison of the WHO 30-cluster sample survey method for estimating immunization coverages (DPT, Polio, BCG, Measles) and an Indian modification of (GOI) was undertaken in five districts in South India. The essential difference between the two methods is the manner in which the first household is selected in the chosen clusters. With the WHO method, it is chosen clusters. With the WHO method, it is chosen at random, whereas with the GOI method it is often close to the village centre. Estimates with the required degree of precision, i.e., 95% confidence limits of +/- 10 percentage points, were provided in 18 (90%) of 20 instances by the WHO method and in 19 (95%) by the GOI method, findings which are in accordance with expectation. The estimated coverages were, however, higher by the GOI method than by the WHO method in two districts, lower in one district, and in the remaining two districts there was no clear pattern. On the average, there was a suggestion that the GOI method yielded slightly higher coverages, but the differences were not statistically significant.

A comparison of a 30-cluster survey method used in India and a purposive method in the estimation of immunization coverages in Tamil Nadu.

A 30-cluster survey method that is employed for estimating immunization coverages by the Government of India (GOI) was compared with a Purposive method, to investigate whether the likely omission of SC/ST and backward classes in the former would lead to the reporting of higher coverages. The essential difference between the two methods is in the manner in which the first household is selected in the chosen first stage sampling units (villages). With the GOI method, it is often close to the village centre, whereas with the Purposive method it is always in the periphery or in a pocket consisting of SC/ST or backward classes. A concurrent comparison of the two methods in three districts in Tamil Nadu showed no real differences in the coverage with DPT and BCG vaccines. However, the coverage was consistently higher by the GOI method in the case of the Polio vaccine (by 1.5%, 3.1% and 5.3% in the 3 districts), and the Measles vaccine (by 4.8%, 13.3% and 13.9%); the average difference was 3.3% for Polio vaccine (p = 0.08) and 7.3% for Measles vaccine (p = 0.01).

Estimation of immunisation coverages in children by WHO 30-cluster survey.

A WHO 30-cluster survey for estimating immunisation coverages in infancy was undertaken in each of 5 districts in Tamil Nadu, strictly according to the specifications laid out in the WHO manual. The main aim was to examine whether the technique would provide estimates with the required degree of precision under Indian conditions. Of 60 sample survey estimates, 57 had the targeted degree of precision (i.e., 95% confidence limits of +/- 10 percentage points), which is in excellent agreement with expectation. The proportions of infants on whom immunisation was initiated, were very high for DPT vaccine (88-99%) and polio vaccine (85-99%); however, of those who had received the first dose, 23-39 per cent did not complete the 3-dose schedule. Estimated coverage with measles vaccine ranged from 15 to 54 per cent, while BCG coverage ranged from 53 to 97 per cent. Better health education regarding the need and correct age for immunisation, and more effective motivation at the time of administration of the first dose of DPT/polio vaccine, are recommended.