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An outbreak of cholera struck Bihar, an Indian state, in August 2008 following a massive flood. Here we report the phenotypic and genotypic characteristics of Vibrio cholerae strains isolated from patients with diarrhea. Rectal swabs were obtained from patients with diarrhea who were admitted to medical camps or the hospital, and the strains were biochemically and serologically characterized. V. cholerae was isolated from 21 (65.6%) of 32 rectal swabs. Serological studies revealed that all the 21 isolates belonged to V. cholerae O1 Ogawa. Mismatch amplification mutation assay (MAMA)-PCR showed that the isolates belonged to El Tor variant group, and pulsed-field gel electrophoresis (PFGE) proved that these isolates were of a different lineage than the conventional El Tor variant strains. These isolates were resistant to several drugs, including ampicillin, streptomycin, tetracycline, nalidixic acid, and furazolidone. The uniqueness of the current report arises from the fact that records of cholera in Bihar are availiable for the early 1960s but not for the next 4 decades. Moreover, the present study is the first to report a cholera outbreak in Bihar that was caused by an El Tor variant strain.

Background & Objectives: An outbreak of chikungunya fever occurred in Malegaon town of Nasik district of Maharashtra state, India during February and March 2006. A total of 4530 fever cases were reported during this period including 1781 cases which were admitted in different hospitals of the town. An entomological and epidemiological investigation was carried out in the affected villages during the outbreak to study the possible causes of the outbreak and to isolate the virus responsible., Methods: Entomological evaluation was done as per WHO guidelines. Sera samples were collected by venipuncture from clinically suspected chikungunya patients in hospitals and also during house-to-house survey in affected villages. IgM antibodies to dengue virus were detected using IgM capture ELISA (PANBIO) and by "Haemagglutination inhibition test" for detection of antibodies against Chikungunya virus. Acute sera samples were inoculated in cell lines for virus isolation. The isolates were confirmed by RT-PCR., Results: On investigation, it was found that water storage containers like cement tanks, plastic containers or earthen pots placed in front of the individual houses were the potential breeding sites for Aedes aegypti. Entomological survey carried out in the most affected areas revealed high Aedes indices. House, container and breteau indices were found to be 27.2, 16.19 and 35.1, respectively. Out of the 13 acute sera samples collected, virus was isolated in 10 samples. The isolates were confirmed by RT-PCR and sequencing using primers from nsP1 gene of Chikungunya virus (CHIKV, Accession No. EF077609, EF077610). Of the 17 convalescent sera tested, significant level of HI antibodies to CHIKV was detected in five samples. One sample was positive for IgM antibodies against dengue virus. Based on clinico-epidemiological features and laboratory findings, the illness was confirmed to be of chikungunya viral disease., Conclusion: Control measures targeting the vector population and personal protective measures against the mosquito bites were instituted. Extensive IEC campaign with the involvement of community and religious leaders helped in containment of the disease.

Entomological surveys were undertaken at some of the international airports/seaports (Bangalore, Calicut, Chennai, Cochin, Thiruvanathapuram and Vishakapatnam) to find out the breeding prevalence of dengue vector mosquito in diverse breeding containers from 1998 to 2004. Three vector indices (House index, Container index and Breateu index) were used to assess the breeding potential at each airport/seaport. International Health Regulations urged national governments to keep all the international airports/seaports and peripheral areas up to 400 meters free from Aedes aegypti mosquitoes. However, surveys revealed high vector indices at all the airports and seaports. Health authorities of airports/seaports need to take cognizance of these facts and develop action plan for appropriate control measures with emphasis on vector surveillance.

The Nilgiri hills provides favourable ecological conditions for the propagation of haematophagous arthropods due to its richness in vegetation and animal fauna. A study was undertaken by the NICD during August to November 1996 on the prevalence of ectoparasitic ticks from different localities of the Nilgiris district of Tamil Nadu state. The ticks were hand picked from various domestic animals of the study area and identified. A total of 1232 adults and immatures of ticks were collected from domestic animals which comprised of the various species in the order of abundance Boophilus microplus, Haemaphysalis bispinosa, Riphicephalus haemaphysaloides and Riphicephalus sanguineus. Studies carried out in the grass lands, meadows and areas adjoining to tea plantations by flagging method revealed mainly immature stages and few adults of Riphicephalus Spp. and Haemaphysalis Spp. The public health importance of the above species have been discussed.

Background: Twenty-five patients of irritable bowel syndrome (IBS) and 25 normal healthy individuals serving as controls, were studied for lactose intolerance., Methods: Hydrogen breath test was used as an investigation after giving 50 g of oral lactose. Clinically, the patients were classified into 3 types of IBS., Results: Eleven (44%) out of 25 patients belonged to diarrhoeal type of IBS, 7 (28%) of 25 patients to spastic and rest 7 (28%) of 25 patients had features of both types of symptoms. Lactose hydrogen breath test was abnormal in 9 cases (82%) of 11 diarrhoeal type of IBS which was significantly higher (p < 0.02) than controls. However, the difference of abnormal hydrogen breath test between spastic type of IBS and patients with features of both types was not significant as compared to controls., Conclusions: These results suggest that patients with diarrhoeal type of IBS have a higher incidence of lactose intolerance as compared to spastic type as well as patients with features of both types.

In 1976, John Rohde, highlighting the importance of diarrhea as prime killer of children in the developing world, beckoned the scientific community to "take science where the diarrhea is". The World Health Organization estimates that one billion diarrheal episodes occur in infants annually resulting in 3.3 million deaths, making diarrheal disease a major contributor to infant mortality in developing world (Bern et al., 1992). The need for simple, effective and inexpensive intervention to treat diarrhea and to prevent its occurrence is urgent and abundantly clear. Among the etiological agents of acute infectious diarrhea rotaviruses account for nearly 25% of hospital admissions in India with vomitting and diarrhea followed by severe dehydration in very young children below 2 years of age (Broor et al., 1985). In developing countries, it has been estimated that more than 870,000 children die from rotavirus infection every year (Perez-Schael, 1996). The discovery of rotavirus by Bishop and colleagues in 1973 initiated a line of research that has progressed rapidly towards the goal of prevention of rotavirus diarrhea (Bishop et al., 1973).

Studies carried out on entomological and rodent surveillance in agroclimatic and feral biotopes of five districts of Maharashtra and two districts of Gujarat revealed that the terrain features of the seven districts surveyed were conducive to wild rodent species, Tatera indica, a natural reservoir of plague and vector flea species, Xenopsylla cheopis. A total of 214 Tatera indica and three Bandicoota bengalensis were collected from burrows by the digging method and 89 rat fleas were retrieved. The flea index calculated ranged from 0.26 to 1.0 in different districts. The examination of blood serum samples, contact tissue impression smears and tissue organs (heart, lung, liver and spleen) of these wild rodents did not reveal any evidence of plague activity. The natural harbourages of Tatera indica were found to be elevated land or raised margins of agricultural fields or barren land with thorny bushes/xerophytic plants and parthenium grass. Agricultural fields having wet soil were found to be the preferred harbourages of Bandicoota bengalensis. Movement of wild rodents toward human settlement was observed to be the common phenomenon during the harvesting season which may lead to the creation of favorable conditions for plague outbreaks.

The synthetic pyrethroid, deltamethrin 2.5% wdp, was evaluated at a dosage of 25 mg/sq m in a group of villages of tribal area around Jagdalpur, District Bastar (Madhya Pradesh). Study was carried out in three consecutive years from 1986 to 1988 with a total of five rounds of deltamethrin spray covering a population of approximately 10,000. The suspension of deltamethrin wdp was white in colour, odourless, non-irritant and the deposits were faintly visible on the surface of wall. A total of 3848 kg of 2.5% deltamethrin wdp was consumed during the trial. Insecticide was found effective in keeping the adult vector density An. culicifacies to a very low level for a period of 14-16 wks. Both anopheline and culicine mosquitoes were affected by the spray. The trial confirmed its long residual effectiveness from 15 to 16 wks on both mud and cement plastered surfaces. Deltamethrin spray shortened the average life span of vector mosquitoes. Observations indicated that insecticide although has an excito-repellent effect on mosquitoes, thus forcing exodus from treated area but with poor survival. Partial impact of deltamethrin spray was observed on the larval population confirm this. Deltamethrin spray did not exhibit any fumigant effect on mosquitoes. Significant decline in SPR from 17.93 to 4.26% was observed in areas sprayed with deltamethrin as compared to the comparison area. Similarly, SfR showed 81% reduction in experimental area while the control area showed increase by 42 per cent. No ill-effect of spray was noticed on the inhabitants, spray personnels, animal population and other non-target organisms of the area. The acceptability of the deltamethrin spray was found to be very high.

Studies carried out in the states of Maharashtra, Gujarat, Uttar Pradesh and Union Territory of Delhi after the bubonic plague outbreak during 1994 revealed the presence of seven species of rodents, viz. Rattus rattus, R. norvegicus, Mus. musculus, Tatera indica, Suncus murinus, Bandicoota bengalensis and B. indica. The flea species encountered were Xenopsylla cheopis and X. astia. The X. cheopis and X. astia index recorded in different areas of Beed district of Maharashtra; Surat, Vadodra and Baruch districts in Gujarat and Varanasi district in Uttar Pradesh and their implications have been discussed. Insecticide suspectibility tests carried out against DDT, dieldrin, malathion and deltamethrin with X. cheopis collected from Maharashtra, Delhi and Varanasi revealed that this vector species is resistant to DDT and dieldrin but susceptible to malathion and deltamethrin. The prevalence and distribution of rodents species, high cheopis index and prevalence of Tatera indica just at the door steps of houses in village Mamla of Beed district provides highly congenital conditions for the intermingling of wild and domestic rodents and transfer of flea population from wild to domestic rodents and vice-versa. These conditions were found to be highly supportive for bubonic plague transmission in the district. The presence of Yersinia pestis antibodies in Rattus rattus collected from Beed, Surat and Varanasi areas are also indicative of bubonic plague in Beed and Varanasi and pneumonic plague in Surat during 1994.

A rapid survey in Delhi and surrounding areas was undertaken in September 1994, during plague outbreak in District Beed (Maharashtra) and Surat (Gujarat) to monitor rodent/flea population and to determine susceptibility status of fleas to insecticides. The five rodent species in order of their prevalence were Rattus rattus (86.06%), Mus musculus (15.33%), Suncus murinus (2.47%), Bandicoota indica (0.48%) and B. bengalensis (0.48%). Two flea species, Xenopsylla cheopis and X. astia, were captured from these rodents. The absolute flea index was found to be ranging between 0.08 to 4.0 in various localities. X. cheopis and X. astia indexes were ranging between 0.22 to 2.08 and 0.08 to 4.0, respectively. Susceptibility test results with X. cheopis collected and reared in the laboratory revealed that it is resistant to DDT and Dieldrin, tolerant to Malathion and susceptible to K-othrin (Deltamethrin).