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P Jambulingam

Publications and source records attributed to P Jambulingam.

At least 19 recordsLinked to original sources
PubMed2006

Muscoid fly populations in tsunami-devastated villages of southern India.

Several coastal villages of southern India were affected by the 26 December 2004 tsunami, and 10,749 people were killed. Investigation carried out in the affected villages during fourth, fifth, and sixth weeks posttsunami showed that the fly density was in the range of 12-91.8 flies per sweep net. In total, 3,259 flies belonging to eight species, namely, Musca domestica L., Musca vicina Macquart, Musca sorbens Wiedemann, Calliphora erythrocephala Robineau-Desvody, Sarcophaga ruficornis F., Chrysomyia sp. Robineau-Desvody, Chlorops sp., and Fannia sp. Robineau-Desvody, were recorded. M. domestica was the predominant species constituting 78.2% of the total flies collected. Density of flies was the highest in temporary shelters constructed for the victims, followed by centralized kitchens and devastated human settlements. Lack of waste control at centralized kitchens nearer to the shelters might be the reason for the high fly density in relief shelters. Under these circumstances, outbreak of fly-borne diseases is likely to be aggravated. Therefore, it is suggested that the ongoing space spraying be supplemented with effective waste control measures to reduce the high density of flies.

Animals↗
PubMed2005

Reappearance of Anopheles minimus in Singhbum hills of East-Central India.

Anopheles minimus, an important malaria vector of South East Asia, has reappeared in the Singhbum hills, East-Central India where deforestation and DDT residual spraying had reportedly eliminated it during the Malaria Eradication Programme. The species reported has been identified as sibling species A of the An. minimus complex. An. minimus is susceptible to both deltamethrin and DDT. The study shows that the environmental conditions in this region still favour the existence of the species and one of the possible reasons for its reappearance may be the scaling down of residual insecticide spraying in the area.

Animals↗
PubMed2005

DDT indoor residual spray, still an effective tool to control Anopheles fluviatilis-transmitted Plasmodium falciparum malaria in India.

This study from two districts of Orissa State which are endemic for Plasmodium falciparum transmitted by Anopheles fluviatilis and A. culicifacies investigated the impact of dichlorodiphenyl trichloroethane (DDT) indoor residual spraying, in view of the ongoing discussion on phasing out DDT in India. Based on their high annual parasite incidence and logistical considerations, 26 villages in Malkangiri and 28 in Koraput district were selected for DDT spraying. For comparison, six and four unsprayed villages were chosen from the same districts. In each district, the prevalence of malaria infection and incidence of malaria fever, indoor resting density and parous rate of the vectors, and their susceptibility to DDT were monitored in six and three villages selected randomly from the sprayed and unsprayed groups respectively. Anopheles fluviatilis was susceptible to DDT while A. culicifacies was resistant. DDT residual spraying with 1 g/m(2), was carried out in October-November 2001. Spraying 74-86% of human dwellings and 100% of cattle sheds brought down the indoor resting density of A. fluviatilis by 93-95%. This was associated with a significant reduction of incidence of malaria fever as well as prevalence of malaria infection from November to February in both districts. The spraying also seemed to impact on vector longevity, and a residual effect of DDT on the sprayed walls was observed up to 10-12 weeks despite re-plastering. Hence DDT spraying can still be an effective tool for controlling fluviatilis-transmitted malaria. Although this species is exophilic, its nocturnal resting behaviour facilitates its contact with the sprayed surfaces. DDT is still useful for residual spraying in India, particularly in areas where the vectors are endophilic and not resistant.

Animals↗
PubMed2005

Laboratory evaluation of fipronil against Periplaneta americana & Blattella germanica.

BACKGROUND & OBJECTIVE: In cockroach control, bait formulations are extensively used. Fipronil is one of the broad spectrum insecticides from phenyl pyrazole family available in bait formulation. The compound has been tested under field conditions. However, information on its effectiveness on different surfaces and at various density levels is not known. Therefore, the efficacy of a new formulation of fipronil 0.03 per cent (Goliath gel) was tested under laboratory conditions. METHODS: The bait formulation was tested against Periplaneta americana at the dosages of 0.025, 0.05, 0.1, 0.15 and 0.2 g/m(2), and Blatella germanica at 0.025, 0.05, 0.075, 0.1 and 0.125 g/m(2) on wood, cement, mud and thatch surface with three density levels of cockroaches viz., 5, 10 and 20 numbers/m(2). Mortality after 24 h of exposure was observed daily for five days. RESULTS: Rate of mortality varied between 16.0 and 96.0 per cent in P. americana and 51.0 and 100.0 per cent in B. germanica on different surfaces tested. The mortality rate of P. americana increased line rarly from the dosage 0.025g to 0.15 g/m(2) and at 0.2 g/m(2), it was independent. The LD(80) values of the gel against P. americana at high density were 0.208, 0.246, 0.361 and 0.466 g/m(2) on wood, cement, mud and thatch surfaces, whereas against B. germanica the values were 0.079, 0.081, 0.089 and 0.055 g/m(2) respectively, indicating a significantly (P<0.001) higher efficacy of Goliath gel against B. germanica than P. americana. The results of fitting logistic regression model to the observed percentage mortality with log dose and cockroach density as explanatory variables satisfactorily described the observations at all densities on each surface. The pattern of response to increasing dosages was similar for all the three density levels on each of the surfaces in P. americana and B. germanica. INTERPRETATION & CONCLUSION: The effectiveness assessed against P. americana and B. germanica using logistic regression model suggested that the gel when applied at the appropriate dosages on wood, cement, mud and thatch surfaces could cause >80 per cent mortality of these species in dwellings having these types of surfaces.

Animals↗
PubMed2004

Role of modified CDC miniature light-traps as an alternative method for sampling adult anophelines (Diptera: Culicidae) in the National Mosquito Surveillance Programme in India.

The efficiency of modified CDC miniature light-traps for sampling adult mosquitoes was evaluated in comparison with indoor resting, outdoor resting, indoor man-landing and outdoor man-landing collections in the hilly district of Koraput, Orissa, India. Overall, light-traps captured 78% of adult mosquitoes collected by all methods. Of the 16 anopheline species recorded in the study area, light-traps effectively sampled 13, contributing about 72% of the total anophelines collected by all methods. Light-traps also caught a large number of female Culex vishnui Theobald (96%). As fully-fed mosquitoes were predominant (82%) and caught alive, light-traps can be used to catch large numbers of vector mosquitoes for studies on vector prevalence, distribution, vector incrimination and also for laboratory bioassays. Light-trap and indoor resting collections revealed similar seasonal trends in numbers of Anopheles culicifacies Giles, A. fluviatilis James, A. jeyporiensis James, A. vagus Doenitz, and A. splendidus Koidzumi. Age-structure of the samples did not vary significantly between the two methods. Light-traps could be used as an alternative to daytime indoor resting collections to monitor the seasonal fluctuations in the abundance and parity rates of these species. The light-trap collections correlated with indoor and outdoor man-landing collections of A. jeyporiensis and the outdoor man-landing collections of A. maculatusTheobald in measuring seasonal trends. Light-trap collections can thus be used as a substitute for man-landing collections of A. jeyporiensis and A. maculatus.

Animals↗
PubMed2003

Impact of alphacypermethrin treated bed nets on malaria in villages of Malkangiri district, Orissa, India.

The impact of use of bed-nets treated with alphacypermethrin, at 20 mg (ai)/m2, in comparison to untreated nets or no nets on malaria vectors and malaria incidence was studied in tribal villages of Malkangiri district, Orissa state, India, which are highly endemic for falciparum malaria. Treated or untreated nets were supplied to the villagers in June 1999 and the nets were re-treated in September 1999, just before the rise in vector abundance and malaria incidence. The seasonal pattern of indoor resting Anopheles fluviatilis females was similar in all the three groups of villages before the start of intervention and the indoor resting catches were not significantly different between treatment-groups (two-way ANOVA, F = 1.53; d.f. = (2, 78); P = 0.2). During intervention, the indoor resting catches differed significantly among treatment groups (two-way ANOVA, F = 38.9; d.f.= (2, 66); P < 0.005). There was a 99% reduction in the indoor resting catches of An. fluviatilis in villages with treated nets and 61% reduction in villages with untreated nets compared with no-net villages. Comparison between villages with and without treated nets showed that there was 97% reduction in indoor resting catches in villages with treated nets. Pair-wise comparison showed that the reductions between villages with and without nets as well as between villages with treated and untreated nets were significant (Dunnett's C-test, P < 0.05). The indoor resting catches of Anopheles culicifacies did not differ significantly among the three groups of villages either before (F = 0.99; d.f. = (2, 121); P = 0.4) or during intervention (F = 0.21; d.f. = (2, 66); P = 0.8). Bioassay with 3 min exposure to treated bed nets showed 100% mortality of An. culicifacies for 2 months and with An. fluviatilis for 4.5 months after which tests were not carried out. In villages with treated nets, the Annual Parasite Incidence (API) significantly declined (P < 0.05) by about 65.7% and prevalence of infection among children (< 15 years) declined by 57.1%, whereas in villages with untreated nets, there was only 34% reduction in API and 13% in the prevalence of infection. In villages with treated nets, there was 48% reduction in API and 64% in prevalence of infection compared with villages with untreated nets. The impact of use of treated bed nets on other arthropod pests lasted for at least 1.5 months. After 1.5 months, observations on arthropod pests were not continued. The use rate of treated nets varied from 49.8 to 93.7% in three seasons and about 68.3% of treated bed nets and 60% of untreated nets were in good condition 1 year after distribution. Out of 489 users of treated net, five people complained of a burning sensation on the face (skin irritation) for 5 days following the distribution of treated nets. There were no other complaints of any discomfort in using the treated nets. The use of alphacypermethrin treated bed nets at 20 mg (ai)/m2 can be one of the options for reducing the vector abundance and incidence of malaria in this area.

Animals↗
PubMed2003

A simple and rapid DNA extraction method for the detection of Wuchereria bancrofti infection in the vector mosquito, Culex quinquefasciatus by Ssp I PCR assay.

A simple, rapid and inexpensive method for the extraction of DNA from filarial vector, Culex quinquefasciatus, useful in Ssp I PCR assay for xenomonitoring of infection with Wuchereria bancrofti is presented. The DNA extracted by this method was found suitable for PCR detection of W. bancrofti infection in pools of 10-30 mosquitoes. The PCR assay employing the simplified DNA extraction method was evaluated for its sensitivity on field caught Cx. quinquefasciatus, in comparison with the conventional dissection and microscopy technique. When assayed on dissection washings of vector mosquitoes the PCR assay detected 45 pools out of 49 dissection positive pools as positive for infection and hence found to be less sensitive than the conventional technique. The reason for detecting four dissection positive pools as negatives by the PCR assay may be due to the loss of a few numbers of parasites (1-3) present in these pools during the transfer of washings of dissected mosquitoes. The PCR assay detected ten out of 72 dissection negative pools as positives, while it did not detect any of the 62 known negative (laboratory reared, uninfected) mosquito pools as positives. When 38 pools (10 mosquitoes/pool) of intact mosquitoes were assessed for infection by each method, the infection rates obtained by the two methods were almost similar (3.35 and 3.01%, respectively, for conventional method and PCR assay). The results thus show that the DNA extraction method, which is simple, rapid, safe and inexpensive, is efficient to generate DNA from vector mosquitoes useful in PCR assay and hence has potential application in xenomonitoring.

Animals↗
PubMed2003

Efficacy of two organophosphorus insecticides, Reldan & Dursban against the larvae of Culex quinquefasciatus.

BACKGROUND & OBJECTIVES: The resistance in vectors to conventional insecticides warrants development of newer insecticides for mosquito control besides use of other counter-measures. The present study was undertaken to test the efficacy of a new and toxicologically safe organophosphorus compound, Reldan (chlorpyrifos-methyl) and compare its efficacy with Dursban (chlorphyrifos-ethyl) against larvae of different mosquito vectors under laboratory conditions and against Culex quinquefasciatus in three larval habitats. METHODS: The susceptibility of larvae of mosquito vector species to Reldan and Dursban was determined by following the standard procedure and the LC50 in mg/l values were calculated by probit analysis. The insecticides were evaluated in the larval habitats of C. quinquefasciatus in and around Pondicherry. The percentage reduction in larval density was calculated using Mulla's formula and duration showing more than 80 per cent reduction was calculated by annotating the graph obtained by plotting percentage reduction in larval density against days of post-treatment. RESULTS: Dursban and Reldan were effective against Anopheles fluviatilis larvae at lower LC50 of 5.90 x 10(-7) and 1.07 x 10(-9) mg/l respectively compared to other species of mosquitoes. Dursban and Reldan were equally effective against Aedes aegypti, An. stephensi and An. culicifacies. Reldan was about nine times more effective than Dursban against C. quinquefasciatus with respective LC50 of 1.17 x 10(-4) and 1.34 x 10(-3) mg/l. Field evaluation of these insecticides against C. quinquefasciatus showed that Reldan and Dursban at the application rate of 500 g (ai)/ha reduced immature density by more than 80 per cent for a mean duration of 4.0 and 4.5 days and 4.6 and 3.7 days in cesspits and cement tanks respectively. In U-drains, at 500 g (ai)/ha, Reldan was effective for a period of 3.6 days whereas, Dursban was not effective. It was effective for 4.0 days only at 1000 g(ai)/ha. There was no significant increase in the residual activity of both Dursban and Reldan with increase in application rates. INTERPRETATION & CONCLUSION: In view of the lack of sustained control with the applications, it is inferred that these insecticides will be of limited use as larvicides against C. quinquefasciatus breeding in polluted habitats.

Animals↗
PubMed2001

rDNA-ITS2 polymerase chain reaction assay for the sibling species of Anopheles fluviatilis.

Species-specific differences in the nucleotide sequences of the second internal transcribed spacer (ITS2) region of the ribosomal DNA (rDNA) were used to develop a diagnostic polymerase chain reaction (PCR) assay for two of the sibling species of the Anopheles fluviatilis complex, members of which are major vectors of malaria in central and northern parts of India. This assay consisted of a three primer reaction, which could amplify the DNA of both the species producing fragments of two distinct sizes, 350 bp for species X and 450 bp for species Y, respectively. The assay was found to be highly specific and sensitive.

Animals↗
PubMed2001

Laboratory & field evaluation of controlled release formulation of the insect repellents N,N-diethyl-m-toluamide (DEET) & N,N-diethyl phenylacetamide (DEPA) against mosquito vectors.

BACKGROUND & OBJECTIVES: Repellents can play a useful role in reducing the man-vector contact and help in interrupting disease transmission. Newer formulations are necessary to improve the efficacy of the repellent on the treated sites for enhanced protection. METHODS: To determine the comparative efficacy, 20 per cent liposphere lotion formulation and 20 per cent alcohol solution of two insect repellents DEET and DEPA were evaluated for the extent of protection on rabbits against Aedes aegypti during the day in the laboratory and on human volunteers during the night against Culex quinquefasciatus in the urban areas of Pondicherry, India. RESULTS: In the laboratory, the lotion formulations of DEPA and DEET were found to enhance the repellency by 1.5 (4.00 to 6.00 h) and 1.25 (4.00 to 5.00 h) times respectively compared to the alcohol solution of the repellents against Ae. aegypti at the application rate of 0.5 mg/cm2. In the field, the lotion formulation of DEPA at 0.3 mg/cm2 could increase the protection time from 6.30 to 8.36 h (1.3 times) whereas the lotion formulation of DEET at 0.3 mg/cm2 could increase the protection time from 6.54 to 8.42 h (1.2 times). INTERPRETATION & CONCLUSION: In laboratory and field tests, the lotion formulations of both repellents were found to give a higher protection compared to alcohol solution. The lotion formulations of DEET and DEPA were found to be equally effective.

Acetamides↗
PubMed2000

Efficacy of aqueous suspension and granular formulations of Bacillus thuringiensis (Vectobac) against mosquito vectors.

The efficacy of aqueous suspension (AS) and granular (G) formulation of Bacillus thuringiensis var. israelensis (Vectobac) was tested against the immatures of mosquito vectors in the laboratory and under field conditions. Laboratory tests showed that the aqueous suspension was relatively more effective against Culex quinquefasciatus than Aedes aegypti and Anopheles stephensi, the respective LC(50) values being 0.046, 0.060 and 0.190 mg/l. In stream pools, with the application of Vectobac AS at 1.2 l/ha, more than 80% reduction in immature density of Anopheles larvae (Anopheles fluviatilis and Anopheles culicifacies) was observed for 2-8 days, and at 2.4 l/ha for 3.5-9.0 days. At the dosage of 7.0 kg/ha of the granular formulation, a reduction in immature density by more than 80% was observed for 2-9 days. In polluted habitats such as cesspits, U-drains and cement tanks, the effectiveness of Vectobac AS lasted for 1-4 days when applied at 1.2 and 2.4 l/ha, and Vectobac G was effective for 1-3 days at application rates of 7. 0 and 14.0 kg/ha against C. quinquefasciatus. There was no significant difference in the effectiveness between the two formulations and the two application rates.

Aedes↗
PubMed1999

Field evaluation of Spicbiomoss, a biolarvicidal formulation of Bacillus sphaericus against immatures of Culex quinquefasciatus & Anopheles species.

Spicbiomoss, an aqueous suspension formulation of Bacillus sphaericus was evaluated for its efficacy against immatures of Culex quinquefasciatus at the application rate of 120 l/ha in cement tanks, cesspits and drains in Pondicherry and in drains in Kochi, Kerala. The formulation was also tested against anophelines (Anopheles fluviatilis and An. culicifacies) breeding in stream pools in Malkangiri district, Orissa. In cement tanks and cesspits more than 80 per cent reduction in immature density was observed for a period of 6-13 days (mean 9.8 +/- 1.25 days) and 3-8 days (mean 5.2 +/- 0.7 days) respectively. The same level of reduction was found to last for 1-4 days (mean 2.2 +/- 0.52 days) in drains in Pondicherry and 2-9 days (mean 4.8 +/- 1.17 days) in Kochi. In bunded stream pools 40-79 per cent reduction in immature density of Anopheles was obtained for an average period of 1-7 (mean 3.83 +/- 0.98) days. There was no improvement in the efficacy of the formulation against anophelines even at the higher application rate (240 l/ha). Thus, Spicbiomoss can be used against Cx. quinquefasciatus in an integrated vector management programme.

Animals↗
PubMed1996

Utility of catalytic models in the estimation of incidence and prevalence of malaria in a hyperendemic situation.

Simple catalytic models were used for estimating the true incidence of malaria in hyperendemic villages of Koraput District in Orissa State where Plasmodium falciparum is predominant. The hill top villages recorded a slide positive rate of 45.68. The daily rate of inoculation among infants was estimated to be 0.00781. The inoculation rate was so high that the recovery from one infection was compensated by the subsequent infection and hence the prevalence continued to increase with age. The model adequately represents the observed data for infants but could not be used for estimating the true prevalence in the adult population without incorporating other factors like immunity and superinfection.

Adult↗
PubMed1994

Reliability of light trap sampling for Anopheles fluviatilis, a vector of malaria.

The utility of light traps for sampling Anopheles fluviatilis, the major malaria vector in the hill tracts of Koraput district, Orissa, was assessed. A modified version of the CDC miniature light trap was used in the study. The data generated from light trap collections were analysed and compared with daytime resting, man-biting and night resting collections carried out in parallel. The number per trap recorded in cattle sheds was significantly higher than that recorded in human dwellings. A similar pattern was observed in hand catches of indoor resting population though the difference was not significant. The density recorded from light traps over time was found to have a significant positive linear association with corresponding indoor (r = 0.625; p = 0.0019) as well as outdoor (r = 0.603; p = 0.0029) diurnal resting densities. The proportion with different gonotrophic stages varied significantly between different types of collections. The age structure of A. fluviatilis did not differ significantly with the types of collection. As the light trap catches reflect seasonal fluctuations in the diurnal resting collections, they can justifiably be used in monitoring the relative density of A. fluviatilis in the place of cumbersome hand catch methods. Other uses of light traps are also discussed.

Animals↗