Rapid spread of Chikungunya virus infection in Orissa: India.

Background & objectives : A large number of cases of undiagnosed fever and joint pain were reported from different parts of the State of Orissa since February 2006. Epidemiological and laboratory investigation were carried out to confirm the cause of emerging illness, which was provisionally suspected as Chikungunya (CHIK) fever. Methods: Upon getting the reports of suspected CHIK like illness in different parts of the State, epidemic investigations were carried out in the outbreak affected villages. Case history was recorded, clinical examination undertaken and blood samples collected for seroconfirmation for CHIK IgM antibody using ELISA based kit. Simultaneously vector survey was also carried out. Results: With no previous record of CHIK infection in the State, the first outbreak was confirmed during February 2006. Subsequently, the infection spread to 13 of 30 districts in different episodes covering 79 villages till November 2007. Attack rate was 9-43 per cent in the different outbreaks with average seropositivity of 24 per cent to CHIK specific IgM. Morbidity was high though no deaths were recorded. Aedes aegypti and Ae. albopictus were identified as the possible vectors for transmission. Interpretation & conclusions : The report confirmed emergence of CHIK infection in the State of Orissa, India, and its spread to a larger geographic zone in a short period which warrants public health measures to control further spread.

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.

An evaluation of musculoskeletal disorder and socioeconomic status of farmers in West Bangal, India.

Rice cultivation contains several tasks and workers were compelled to adopt some harmful and awkward posture during performing those tasks. These type repetitive jobs may be related to occupational health hazards like musculoskeletal disorder (MSD). In the present investigation different MSD related problems of the workers have been assessed and also identify the socioeconomic status of the farmers considering the issues of community health development. In this connection a simple and easily applicable questionnaire technique has been apply in the agricultural field during performing rice cultivation tasks. The results showed that a large number of workers could not complete their primary education (33.0% to 43.0%) and remained below the poverty line (91.3%). From the MSD assessment lower back problem was prevalent (48.8%) among the workers when all rice cultivation tasks were consider together, but it was extremely prevalent in reaping job (92.0%) and transplantation job (84.0%). It was concluded that MSD among the workers might be related to the stressful work posture, long duration jobs, nature of jobs and use of ill-fitted hand tools. So, some free-hand exercise, proper work-rest scheduled and awareness program may be helpful for reducing the MSD and proper handling of hand tools.

Iodine deficiency in urban slums of Bhubaneswar.

OBJECTIVE: The present study aimed at assessing the population prevalence of goiter and iodine deficiency in school children of 6-12 yr living in urban slums of Bhubaneswer, the capital city of Orissa. METHODS: A cross-sectional study was performed using the 30-cluster sampling methodology and surveillance methods for iodine deficiency as recommended by WHO/ICCIDD/UNICEF. The total goitre rate (n=1248), urinary iodine concentration (UIC) (n=411) and iodine content of edible salt (n=368) were measured. RESULTS: The goitre prevalence was 23.6% (grade 1=18.9%, grade 2=4.7%) with no significant gender variation. Goitre prevalence was significantly higher in children of 10-12 yr (P=0.012) and scheduled caste and tribe (P=0.003). Median urinary iodine concentration was 50.0 microg/l with 85.7% of children having values less than 100 microg/l, indicating as biochemical iodine deficiency. Median UIC was inversely in association with gradations of goitre. Children of 10-12 yr and scheduled caste/tribe communities had significantly higher median UIC (P=0.001) than their counterpart peers. About 51% of children were consuming salt having stipulated iodine content of 15 ppm. CONCLUSION: The study indicates moderate iodine deficiency in the population, despite a mandatory salt iodization programme in Orissa that has been in force since 1989. There is a need to improve the situation through enforcing monitoring of salt iodization to ensure quality and increasing the level of awareness about the iodized salt for sustainable prevention and control of iodine deficiency.

Mapping of risk prone areas of kala-azar (Visceral leishmaniasis) in parts of Bihar State, India: an RS and GIS approach.

BACKGROUND & OBJECTIVES: The kala-azar fever (Visceral leishmaniasis) is continuing unabated in India for over a century, now being largely confined to the eastern part of India mainly in Bihar state and to some extent in its bordering states like West Bengal and Uttar Pradesh. Two study sites namely Patepur block in Vaishali district with high endemicity in northern part and Lohardagga block in Lohardagga district with absolute non-endemicity in southern part of Bihar were selected for the study with the following objectives : (i) to study the macro-ecosystem in relation to distribution of vector -Phlebotomus argentipes; (ii) to identify/map the risk prone areas or villages in a block for quick remedial measures; and (iii) to make use of satellite remote sensing and GIS to demonstrate the utility for rapid assessment of landuse/landcover and their relation with the incidence of kalaazar leading to the mapping of risk prone areas. METHODS: Indian Remote Sensing (IRS)-1D LISS III satellite data for the periods of March and November 2000 were analysed in Silicon graphic image processing system using ERDAS software. False color composites (FCC) were generated and landuse/landcover was assessed using Maximum likelihood supervised classification techniques based on ground truth training sets. During the study the GIS functions are used to quantify the remotely sensed landscape proportions of 5 km2 buffer surrounding each known group of villages of high occurrence of sandflies in endemic and nonendemic study sites. Instead of traditional ground based survey methods to vector surveillance, the present study used a combination of remote sensing (RS) and geographical information system (GIS) approach to develop landscape predictors of sandfly abundance-an indicator of human vector contact and as a measure of risk prone areas. RESULTS: Statistical analysis using the remotely sensed landscape variables showed that rural villages surrounded by higher proportion of transitional swamps with soft stemmed edible plants and banana, sugarcane plantations had higher sandfly abundance and would, therefore, be at higher risk prone areas for man-vector contact. INTERPRETATION & CONCLUSION: The present study clearly brought out the usefulness of satellite remote sensing technology in generating the crucial information on spatial distribution of landuse/landcover classes with special emphasis on indicator landcover classes thereby helping in prioritising the area to identify risk prone areas of kala-azar through GIS application tools.

A pilot study on the status of lymphatic filariasis in a rural community of Bihar.

A pilot study of lymphatic filariasis was conducted in two contiguous villages of Patna district in Bihar situated at the side of the river Ganges, known to be endemic for lymphatic filariasis, to study present status of transmission parameters of filariasis. Of the 1872 persons examined, 8.4% were found asymptomatic but microfilaraemic. Morbidity pattern due to filarial infection showed an increase with advancement of age and significantly high in males as compared to female (p < 0.001). Acute and chronic filarial disease was observed as 0.5% and 9% respectively. Microfilaria was found in 10% of acute and 11.2% of chronic filarial cases. The Mf rate was found to be 9.9% in males and 9.0% in females respectively. The parasite species was identified as W. bancrofti. The vector fauna surveyed show highest prevalence of vector species of Cx. quinquefasciatus (43%) in both domestic as well as predomestic area in the community. Other species like Cx. vishnui and Ma. uniformis were also seen. Each household and predomestic area was searched for mosquito fauna at night. The infection rate in vectors was found to be 14% and infectivity rate (L3) was 8%. The filariasis cases detected in the study were treated with 12 days course of DEC 6 mg/kg body weight.

Prediction of exposed domains of envelope glycoprotein in Indian HIV-1 isolates and experimental confirmation of their immunogenicity in humans

We describe the impact of subtype differences on the seroreactivity of linear antigenic epitopes in envelope glycoprotein of HIV-1 isolates from different geographical locations. By computer analysis, we predicted potential antigenic sites of envelope glycoprotein (gp120 and gp4l) of this virus. For this purpose, after fetching sequences of proteins of interest from data banks, values of hydrophilicity, flexibility, accessibility, inverted hydrophobicity, and secondary structure were considered. We identified several potential antigenic epitopes in a B subtype strain of envelope glycoprotein of HIV-1 (IIIB). Solid- phase peptide synthesis methods of Merrifield and Fmoc chemistry were used for synthesizing peptides. These synthetic peptides corresponded mainly to the C2, V3 and CD4 binding sites of gp120 and some parts of the ectodomain of gp41. The reactivity of these peptides was tested by ELISA against different HIV-1-positive sera from different locations in India. For two of these predicted epitopes, the corresponding Indian consensus sequences (LAIERYLKQQLLGWG and DIIGDIRQAHCNISEDKWNET) (subtype C) were also synthesized and their reactivity was tested by ELISA. These peptides also distinguished HIV-1-positive sera of Indians with C subtype infections from sera from HIV-negative subjects.

Effect of immunization with lipid associated polysaccharide antigen and anti CD-2 antibodies on class II MHC expression and cellular immune response in BALB/C mice infected with Leishmania donovani.

In a bid to characterize the antigens and immunization mechanisms which may be used to produce a protective response against L. donovani, role of lipid associated polysaccharide (LPS) antigen and whole antigen was evaluated. BALB/C mice were immunized with whole or LPS antigen in combination with one of three putative adjuvents (anti CD-2 antibody/FIA/0.85% Saline). LPS antigen emulsified in anti CD-2 antibody was found to induce significant antibodies in mice on day 28 against challenge with lethal dose of L. donovani. Immunoprophylactic properties of LPS and whole antigen was investigated on day 40 through cytokine elicitation (IL-2), MIF) in culture supernatants of spleen cells, but before that MHC-II expressed on macrophage was studied. The LPS antigen in combination with anti CD-2 antibody was found to be most immuno-reactive inducing higher MHC-II expression on macrophages which was associated with substantial rise in the level of MIF and IL-2. It coincided with decline in antibody titre in 100% mice immunized with LPS antigen while Leishmania injected as whole antigen failed to induce specific macrophage and T-cell response with all the above formulations. We surmise from our data that lipid associated polysaccharide antigen linked to anti CD-2 antibody has potential for eliciting protective immunity against Leishmania.

Vectorial efficacy of Phlebotomus argentipes in Kala-azar endemic foci of Bihar (India) under natural and artificial conditions.

Ability of Phlebotomus argentipes to acquire Leishmania donovani the causative agent of Indian Kala-azar was evaluated in the laboratory. Flies were fed artificially on infected blood suspensions, using a chick-skin-membrane feeding apparatus, and naturally on Leishmania donovani infected mice. In addition flies collected from different endemic areas were dissected and examined for natural infection. Flies fed on infected mice showed significantly higher feeding rate (14.4%, p < 0.01) compared to that of other experiments (9%, 8.75%) but the percentage of infection was very low (2.43%). No Chi-square comparison was made between infection rate and feeding rate because of low value in infection rate (less than 5). Flies dissected for natural infection showed only 0.1% infection. Not much difference was observed in the intensity of Leishmania donovani infection in the mid gut of sandflies examined from any of these experiments. These observations have confirmed that Phlebotomus argentipes has ability to acquire infection and it provides the final piece of evidence that Phlebotomus argentipes is the vector of Leishmania donovani in Bihar State.

A randomized clinical trial of low dosage combination of pentamidine and allopurinol in the treatment of antimony unresponsive cases of visceral leishmaniasis.

OBJECTIVES: A randomized clinical trial of low dosage combination of pentamidine and allopurinol was carried out with objectives to assess the efficacy and toxicity as compared to full dosage of pentamidine in antimony unresponsive visceral leishmaniasis (VL) patients. METHODS: Using a randomized control clinical trial, a total of 158 antimony unresponsive patients of VL were randomly allocated into two treatment groups. Patients in one group (n=80) received half the dosage of pentamidine i.e. 2 mg/kg body weight by IM route on alternate day and allopurinol in dose of 15 mg/kg body weight in three divided dosages for 30 days; patients in the second group (n=78) received pentamidine in dose of 4 mg/kg body weight by IM route on alternate day for 15 injections in 30 days. The efficacy and safety of the two regimens were compared. RESULTS: Apparent cure i.e. clinical and pathological cure at the end of therapy, in 78 (97.5%) and 67 (86%), and ultimate cure i.e. clinical and parasitological cure at the end of follow-up of six months, in 73 (91.25%) and 58 (74.35%) patients was observed in the combination regimen and single regimen group respectively. The difference of the ultimate cure between two groups of the patients was statistically significant (p < 0.01). In single regimen group, 11 (14%) patients showed primary unresponsiveness (with no response during treatment) and nine (13%) relapse (after six months of follow-up) respectively, where as in combination regimen group, two (2.5%) patients showed primary unresponsiveness and five (6.4%) relapse respectively. By the end of the treatment, the incidence of injection-related toxicity, such as rigor and fever, was same in both groups. No hyperglycemia was observed in combination therapy probably due to reduced dose of pentamidine and three patients in single regimen developed hyperglycemia and one of them developed irreversible hyperglycemia. CONCLUSIONS: The study showed that the combination of pentamidine (half dose) and allopurinol is more effective in achieving ultimate cure with an added advantage of reduced toxicity in unresponsive cases as compared to full pentamidine dose.

An entomological field evaluation of larval biology of sandfly in Kala-azar endemic focus of Bihar--exploration of larval control tool.

Knowing the exact breeding places inside the habitat is very important to plan the larval control strategy. Information regarding larval biology in relation to different seasons will be more useful to organize insecticide spray schedule at a particular month of maximum immature density to bring down the adult sandfly density. In the present study, maximum number of soil samples were found positive in the month of January and minimum in the month of September. Maximum positive soil samples were collected from cattle sheds, minimum in mixed dwellings and in case of human dwellings all soil samples were negative. Comparison of two methods for the isolation of immature stages showed that direct microscopic observation is superior to sugar flotation technique.

Relevance of direct agglutination test in seroepidemiological survey of Kala-azar in epidemic foci of Bihar.

The performance of direct agglutination test (DAT) was evaluated under field conditions in three endemic districts of Bihar. In three villages of these districts, 197 households were surveyed with a population of 1167 individuals. Out of 1167 individuals, 603 were clinically examined for VL and blood samples of each examined individual were collected for DAT. The proportion of DAT positivity in both males (32.33%) and females (32.94%) was statistically not significant (p > 0.05). The proportion of DAT positivity in all age groups was observed to be similar (p > 0.05). The GMRT was observed highest in active VL cases. Out of 20 DAT positive individuals having fever, 5 were examined parasitologically (bone marrow aspiration) and in three cases positivity was observed. This showed the relevance of DAT in early diagnosis of visceral leishmaniasis and usefulness of DAT in field conditions.

Field trial of an ecological approach for the control of Phlebotomus argentipes using mud & lime plaster.

A pilot study for the control of Ph. argentipes, a known vector of kala-azar in India, was carried out using an ecological approach. Of the 15 houses selected for the study 10, including the cattle sheds and latrines, were plastered with a mixture of mud and lime, up to a height of 1.22 m taking care to seal all cracks and crevices. The remaining five houses were left unplastered and were considered as control areas. The pre-treatment and post-treatment resting densities of the sandfly were monitored both in treated and untreated houses. A sudden drop in the sandfly density was noticed in the treated houses, whereas there was no significant reduction in the check houses, suggesting an effective control.

The use of ivermectin for scabies.

BACKGROUND. Ivermectin, a modified avermectin, is widely known to be an ectoparasiticidal agent in animals but its effect on human ectoparasites is not known. METHODS. As a part of a chemotherapy trial with ivermectin against Wuchereria bancrofti microfilaraemia, two males with clinical scabies were studied. Three skin scrapings were taken from the lesions of each of the cases and examined with potassium hydroxide solution for the presence of eggs, larvae or adult mites. RESULTS. Following a single oral dose of ivermectin at either 100 micrograms or 20 micrograms/kg body weight both the itching and eruptions were reduced and the lesions healed after 14 days of treatment. Skin scrapings taken on days 7 and 30 after administering the drug did not reveal any mites. However, the lesions reappeared after 3 months. CONCLUSION. The beneficial results on the healing of scabetic lesions following ivermectin therapy indicates that the drug may have a scabicidal effect. Reappearance of the lesions may have been due to an inadequate dose. This emphasizes the need for future controlled trials on the efficacy of ivermectin against human scabies infection. If proven, this may be an additional advantage in mass chemotherapy campaigns, when there is co-existence of filariasis, intestinal helminthiasis and scabies.