An outbreak of cholera associated with an unprotected well in Parbatia, Orissa, Eastern India.

In November 2003, an outbreak (41 cases; attack rate-4.3%; no deaths) of severe diarrhoea was reported from a village in Orissa, eastern India. Thirteen of these cases were hospitalized. A matched case-control study was conducted to identify the possible exposure variables. Since all wells were heavily chlorinated immediately after the outbreak, water samples were not tested. The cases were managed symptomatically. Descriptive epidemiology suggested clustering of cases around one public well. Vibrio cholerae El Tor O1, serotype Ogawa was isolated from four of six rectal swabs. The water from the public well was associated with the outbreak (matched odds ratio: 12; 95% confidence interval 1.2-44.1). On the basis of these conclusions, access to the well was barred immediately, and it was protected. This investigation highlighted the broader use of field epidemiology methods to implement public-health actions guided by epidemiologic data to control a cholera epidemic.

Two sequential outbreaks in two villages illustrate the various modes of transmission of cholera.

We investigated two sequential outbreaks of severe diarrhoea in two neighbouring villages of Orissa, in 2005. We conducted descriptive and matched case-control studies. The attack rates were 5.6% (n=62) and 5.2% (n=51), respectively, in the first and second villages. One death was reported in the second village (case fatality 2%). We identified that consumption of milk products prepared in the household of the index case [matched odds ratio (mOR) 5.7, 95% confidence interval (CI) 1.7-30] in the first village, and drinking well water in the second village were associated with the illness (mOR 4.7, 95% CI 1.6-19). We isolated Vibrio cholerae El Tor O1 Ogawa from stool samples from both the villages. Mishandling of milk products led to a cholera outbreak in the first village, which led to sewerage contamination of a well and another outbreak in the second village. Environmental contamination should be expected and prevented during cholera outbreaks.

Molecular variants of G6PD deficiency among certain tribal communities of Orissa, India.

This study investigated the extent of molecular heterogeneity of the G6PD enzyme among certain aboriginal (tribal) populations of Orissa, an eastern Indian state, which is hyperendemic for Plasmodium falciparum malaria. A total of 3480 males from 14 tribal communities were screened, and 223 (6.4%) individuals were found to be G6PD deficient. Molecular analysis revealed that 59.2% of deficient individuals had the G6PD Orissa mutation and 37.2% had the G6PD Mediterranean mutation. The presence of G6PD Med has not been previously reported among the tribal populations of Orissa. Interestingly, both G6PD Med and G6PD Orissa were found among communities belonging to the Mundari (Austroasiatic) linguistic group, while G6PD Med was exclusive to Dravidian and G6PD Orissa to Indo-Aryan groups. Erythrocytic G6PD enzyme activity was severely reduced in the case of G6PD Med type (0.64-1.1 IU/g Hb) as well as among the uncharacterized samples, but was moderate in G6PD Orissa type (1.2-3.1 IU/g Hb). Anaemia was moderate among the individuals with G6PD Med mutation and mild among individuals with G6PD Orissa mutations. The prevalence of G6PD deficiency as well as molecular variants of the Gd- gene is highly heterogeneous among the tribal population of Orissa. The high endemicity of P. falciparum malaria has probably selected two different molecular variants of Gd- at different points in time, which is discussed.

Distribution of Plasmodium falciparum genotypes in clinically mild and severe malaria cases in Orissa, India.

A cross-sectional study was conducted in a malaria hyperendemic state of India to ascertain the distribution of Plasmodium falciparum genotypes in patients with mild (n=40) and severe (n=35) malaria. PCR and nested PCR were used to determine the glutamate-rich protein (GLURP), merozoite surface proteins 1 and 2 (MSP1 and MSP2) and knob-associated histidine-rich protein (KAHRP) for characterization of the parasite. The results indicate that (i) the 200bp allele of the MAD20 family of MSP1 and the 550bp allele of the 3D7 family of MSP2 show over-representation in severe malaria cases; (ii) the multiplicity of infection with respect to MSP2 alleles is significantly higher (P<0.001) in severe cases than in mild cases; and (iii) comparison with the findings of other studies leads to the conclusion that the distribution of P. falciparum genotypes between different clinical groups differs geographically.

Precontrol observations on lymphatic filariasis & geo-helminthiases in two coastal districts of rural Orrisa.

BACKGROUND & OBJECTIVE: Lymphatic filariasis (LF) is a major public health problem in India, accounting for 40 per cent of the global burden. The World Health Organization has launched a global programme to eliminate LF by 2020 and India is a signatory to it. Orissa, an eastern Indian State has long been known to be endemic for LF. Prior to implementation of mass drug administration programme it is important to collect baseline data on filariasis and geo-helminthiases in the State. The present cross-sectional survey was therefore carried out between February and December 2001 to obtain baseline information on both LF and geo-helminthiases before application of the control measures. METHODS: The study was carried out in rural areas of Puri and Ganjam districts in two phases. In phase I, the distribution of microfilaraemia in two district was mapped out in randomly selected primary health centres (PHCs), and 12 microfilaraemic villages were identified in each district by cluster analysis for the phase II study. In phase II, detailed clinical and parasitological survey for LF and geo-helminthiases was carried out following the standard procedures. RESULTS: Wuchereria bancrofti was found to be widely prevalent in Puri district with certain pockets of Brugia malayi while W. bancrofti was the only species in Ganjam district. The microfilaraemia (Mf) rate was found to be 9.5 and 11.1 per cent; and circulating filarial antigenaemia (CFA) was 16.8 and 17.8 per cent in Puri and Ganjam respectively. The geometric mean intensity (GMI) of Mf per ml of blood among positive individuals was 387 in Puri and 454 in Ganjam. The overall disease rate in Puri was 7.9 and 8.9 per cent in Ganjam. The prevalence of chronic manifestations was found to be significantly higher (P<0.001) than the acute manifestations in both the districts. The prevalence of geo-helminthiases was 31.8 per cent in Puri and 42.1 per cent in Ganjam; and the heavy infection was found to be significantly higher (P<0.001) in Ganjam compared to Puri district. INTERPRETATION & CONCLUSION: The present study identified LF and geo-helminthiases as widely distributed health problem in rural areas of coastal Orissa which warrants intervention measures along the lines recommended by the global programme for elimination of LF and geo-helminthiases to reduce the disease burden.

The PfCRT (K76T) point mutation favours clone multiplicity and disease severity in Plasmodium falciparum infection.

In Orissa, a malaria-hyperendemic area of India, we assessed the relationship between the PfCRT (K76T) point mutation of Plasmodium falciparum and the clinical severity of malaria. Forty uncomplicated and 36 severe malaria cases were selected, and parasite species, density and schizontaemia determined by examination of Giemsa-stained thick or thin blood films. The PfCRT point mutation was analysed by PCR-RFLP and genotypes of the parasite isolates investigated by nested PCR using the polymorphic region of the merozoite surface protein-2. We found that (i) the prevalence of the PfCRT point mutation was significantly higher (P < 0.01) in severe malaria cases and that (ii) heavy parasitaemia along with clone multiplicity was statistically more common (P < 0.01) in severe cases. These associations may be due to progression of uncomplicated to severe disease after chloroquine treatment failure and/or increased virulence of chloroquine-resistant parasites. The implications for antimalarial treatment policy are discussed.

Knowledge and beliefs about elephantiasis and hydrocele of lymphatic filariasis and some socio-demographic determinants in an endemic community of Eastern India.

This study reports the knowledge and beliefs about filarial elephantiasis and hydrocele of people from an endemic area of Orissa, India. Both qualitative and quantitative data were collected from 12 villages, sampled from four blocks in the Khurda district of Orissa. This study found that people were aware of different manifestations of filariasis, and perceived them as problems in their community. A high proportion of people knew that mosquitoes are the reason for the spread of elephantiasis, but less people were aware of the cause of hydrocele and the association between elephantiasis and hydrocele. Only half of the respondents believed that elephantiasis is curable by modern medicines, and about 84% of respondents thought that surgery is the only method to cure hydrocele. About two-thirds of people know that avoiding mosquitoes can prevent elephantiasis. Age, gender, educational level and caste affiliation were identified as factors influencing awareness and knowledge. These findings may be used in the development of group-specific health education programmes to change health behaviour and to achieve higher involvement of the community in annual mass drug administration to eliminate lymphatic filariasis.

Emergence of novel human group A rotavirus G12 strains in India.

Three rare human G12 strains were detected from diarrheic clinical samples of children (<8 months of age) in Calcutta during a routine surveillance study of rotaviral diarrhea in India. The VP7 genes of G12 strains and their products showed maximum homology (97 to 99% at the nucleotide level and 98% at the amino acid level, respectively) with those of two recently reported G12 strains (from the United States and Thailand) but lesser homology with those of prototype G12 strain L26.

Drug abusers - a new high risk population for HIV infection in Orissa.

The present study reports the prevalence of HIV infection among the drug addicts undergoing counselling and treatment in a drug deaddiction centre located in Bhubaneswar, during July 1996 to August 1997. All subjects were males. The coded serum samples were tested by ELISA and rapid spot test for the detection of HIV antibodies. The positive samples were finally confirmed by the line immunoassay for HIV infection. A high prevalence of 7% HIV infection was noticed among the drug addicts (n=100). Oral drug abusers and IDUs were positive for HIV-1 infection in 5.26% and 21.74% cases respectively. The present study reveals a high prevalence of HIV infection among the drug addicts for the first time from Orissa which needs a careful monitoring and surveillance.

Microscopic haematuria as an occult filarial infection in bhubaneshwar an endemic area for bancroftian filariasis.

Sera samples of 7 microscopic haematuria cases collected before and after treatment with Diethylcarbamazine citrate, (DEC), 9 microfilaraemic cases and 19 endemic normal individuals were analysed for filarial antigen and IgG antibody levels. Filarial antigen was detected in 5 of the 7 microscopic haematuria cases, of which 3 turned negative for antigen after treatment with DEC. While none of the 7 haematuria cases were positive for filarial IgG antibodies, before the DEC treatment, all of them turned positive after DEC treatment. The sensitivity and specificity values(to detect mf +ve cases) were 89% and 90% respectively for the detection of filarial antigen and 78% and 95% respectively for the detection of filarial IgG antibodies.

Incidence and molecular analysis of Vibrio cholerae associated with cholera outbreak subsequent to the super cyclone in Orissa, India.

An epidemiological study was carried out to find out the aetiological agent for diarrhoeal disorders in the cyclone and flood affected areas of Orissa, India. Rectal swabs collected from 107 hospitalized diarrhoea patients were bacteriologically analysed to isolate and identify the various enteropathogens. Detection of toxic genes among E. coli and V. cholerae was carried out by polymerase chain reaction (PCR) assay. Of the 107 rectal swabs analysed, 72.3% were positive for V. cholerae O1 Ogawa, 7.2% for V. cholerae O139, 1.2% for E. coli (EAggEC) and 1.2% for Shigella flexneri type 6. Using multiplex PCR assay it was found that all V. cholerae isolates were ctxA positive and El Tor biotype. Strains of V. cholerae O1 were observed to be resistant to nalidixic acid, furazolidone, streptomycin, co-trimoxazole and ampicillin. Except for nalidixic acid, the resistance pattern for O139 was identical to that of O1 strains. Representative strains of V. cholerae were further characterized by randomly amplified polymorphic DNA (RAPD) analysis and ribotyping. Both O1 and O139 V. cholerae strains exhibited the R3 pattern of ribotype and belonged to a similar pattern of RAPD compared with that of Calcutta strains. Early bacteriological and epidemiological investigations have revealed the dominance of V. cholerae O1 among the hospitalized patients in cyclone affected areas of Orissa. Drinking water scarcity and poor sanitation were thought to be responsible for these diarrhoeal outbreaks. Timely reporting and implementation of appropriate control measures could contain a vital epidemic in this area.

Retrospective analysis of epidemiological investigation of Japanese encephalitis outbreak occurred in Rourkela, Orissa, India.

There was an outbreak of Japanese encephalitis (JE) during July/August of 1993 in Rourkela City of Orissa, India. Among the serum samples, 40% of the sera showed antibodies against JE, while 17% of the sera showed recent infection to dengue virus. As many as 15 species of mosquitos were encountered in and around the affected areas. Species like Culex tritaeniorhynchus, Cx, vishnui, Cx. pseudovishnui and Cx. bitaeniorhynchus constituted 19% of the total collections. The above species were resistant to DDT and dieldrin, but susceptible to malathion.

A clinico-epidemiological perspective of lymphatic filariasis in Satyabadi block of Puri district, Orissa.

BACKGROUND & OBJECTIVES: Lymphatic filariasis is a major public health problem in the coastal district of Orissa. However, no systematic studies have been done to document the prevalence of microfilaraemia/disease in different regions of the State. Therefore, the present cross sectional study was undertaken during 1996-97 to obtain information on the clinical and epidemiological status of the disease in Satyabadi block area of Puri district, known to be endemic for filariasis. METHODS: Night blood smear survey and clinical examinations were performed on 4646 individuals aged 0-> or = 60 yr from systematically selected households of 17 randomly selected villages of the Block. Microfilaraemia was detected by thick drop technique using 20 microliters of peripheral blood and microfilariae (mf) density by nucleopore filtration technique collected during 1900-2300 h. RESULTS: The prevalence of microfilaraemia was observed to be 14.8 per cent; 13.3 per cent Wuchereria bancrofti, 1.4 per cent Brugia malayi and 0.09 per cent had mixed infections. Geometric mean microfilaraemia density (infected persons only) was found to be 1288 per ml in case of W. bancrofti and 204 per ml in case of B. malayi. The disease rate was observed to be 19.8 per cent; 12.85 per cent had acute manifestations and 6.97 per cent had chronic manifestations. INTERPRETATION & CONCLUSION: The rate of acute disease manifestations was observed to be significantly higher (P < 0.001) than chronic manifestations. There was a male preponderence among the affected individuals (P < 0.001). The interesting observations of the study were the occurrence of occult filarial manifestations viz., tropical pulmonary eosinophilia (TPE) in 0.47 per cent cases and other associated manifestations like asymptomatic microscopic haematuria, monoarticular arthritis and filarial associated respiratory diseases in 0.50, 0.24 and 0.19 per cent of cases respectively. The present study indicates that the area is highly endemic for lymphatic filariasis with active transmission.

Occurrence of asymptomatic microscopic haematuria in a filarial endemic area of Orissa, India.

To determine the frequency of occurrence of asymptomatic microscopic haematuria in filarial endemic area of Orissa, where the mf rate and disease rate were observed to be 14.8% and 37.2% respectively, clinical examination, night blood smear examination, morning midstream urine examination were conducted on 697 persons-randomly selected from all age groups in 8 villages of Puri tehsil. Out of them, 15.6% were found to have asymptomatic haematuria (Grade I-14.7%, Grade II-0.6%, Grade-III 0.3%). The prevalence of asymptomatic microscopic haematuria was observed to have positive statistical correlation with mf status (P < 0.001), filarial antigenaemia (Ag) (P < 0.001), antibody (Ab) (P < 0.001) and circulating immunocomplex antigen (CIC-Ag) (P < 0.001). The prevalence was also found to be increased with the progression of the disease process i.e. from endemic normal to chronic manifestations. None of the cases having Grade-II and III haematuria cases revealed any gross renal pathological lesions, when subjected to special investigations like X-ray, IVP, cystoscopy and urethroscopy.

A new glucose-6-phosphate dehydrogenase variant, G6PD Orissa (44 Ala-->Gly), is the major polymorphic variant in tribal populations in India.

Deficiency of glucose-6-phosphate dehydrogenase (G6PD) is usually found at high frequencies in areas of the world where malaria has been endemic. The frequency and genetic basis of G6PD deficiency have been studied in Africa, around the Mediterranean, and in the Far East, but little such information is available about the situation in India. To determine the extent of heterogeneity of G6PD, we have studied several different Indian populations by screening for G6PD deficiency, followed by molecular analysis of deficient alleles. The frequency of G6PD deficiency varies between 3% and 15% in different tribal and urban groups. Remarkably, a previously unreported deficient variant, G6PD Orissa (44 Ala-->Gly), is responsible for most of the G6PD deficiency in tribal Indian populations but is not found in urban populations, where most of the G6PD deficiency is due to the G6PD Mediterranean (188 Ser-->Phe) variant. The KmNADP of G6PD Orissa is fivefold higher than that of the normal enzyme. This may be due to the fact that the alanine residue that is replaced by glycine is part of a putative coenzyme-binding site.

Prevalence of G-6-PD deficiency in a malaria endemic tribal area of Orissa (India).

A total of 207 men belonging to Bhuyan, Juanga and Munda tribes and 108 non-tribal residents of Banspal block area of Keonjhar district of Orissa were screened for glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, abnormal haemoglobin and malaria parasite. In the tribal group, G-6-PD enzyme deficiency was observed in 13.52 per cent as compared to 3.70 per cent in non-tribals. No abnormal haemoglobin was detected in the studied population, while 15.87 per cent of individuals were positive for Plasmodium falciparum. An extremely weak association was observed between malaria and G-6-PD deficiency.

Effect of drug treatment on the prevalence of intestinal parasites amongst school children in a sub-urban community.

The prevalence of intestinal protozoal and helminthic infection was studied over a period of one year amongst 297 school children, aged 5-20 yr in a sub-urban area. The overall prevalence rate of various protozoal infection, 15.82 per cent had only helminthic infection and 14.47 per cent had combined helminthic and protozoal infection. Ascaris lumbricoides infestation was found to be the commonest helminthic infection (61.70%) while giardiasis was the commonest protozoal infection (59.80%). The prevalence rates, one year after effective anti-protozoal and antihelminthic treatment was administered, were overall parasitic infection 25.92 per cent; only protozoal infection 17.50 per cent, only helminthic infection 5.72 per cent and combined infection 2.69 per cent. The reinfection rate was found to be 7.40 per cent and the fresh infection rate was found to be 11.4 and 39.8 per cent at the end of six months and one year respectively.