Field trial of cyfluthrin as an effective and safe insecticide for control of malaria vectors in triple insecticide resistant areas.

Cyfluthrin (Solfac**) 10 wp, a synthetic pyrethroid was evaluated for its efficacy in malaria control through primary health centre approach, and for its acceptance by the community and effect on human health, and non target organisms, in predominantly tribal areas of Maharashtra and Gujarat from 1988 to 1990. Two dosage schedules; 2 rounds of indoor residual sparying a year, at 25 mg/sq. m2 in Maharashtra, and 3 rounds a year at 15 mg/sq. m2, in Gujarat were followed. There was significant reduction in per man hour densities of An. culicifacies the principal malaria vector, and collaterally of C. quinquefasciatus also. Significant reductions in slide positivity rates and slide falciparum rates were observed in both the areas as compared to the controls. The community acceptance of Cyfluthrin in terms of room coverage was 96% in Gujarat, and 89% in Maharashtra, as against average 68.5% and 55% in case of DDT and Malathion respectively. There were no reported ill-effects on humans or non-target organisms.

Eliminating leprosy as a public health problem--is the optimism justified?

Systematic use of multidrug therapy has proved to be so effective that leprosy can be eliminated as a public health problem by the end of the century. However, because of the long incubation period of this disease, together with the time-lag in case detection, the factors involved in achieving and sustaining its elimination have to be very carefully defined.

Rapid and sensitive spectrophotometric determination of cerium(IV) with 2,4-dihydroxy benzophenone benzoic hydrazone.

A simple and sensitive spectrophotometric method for the determination of cerium(IV) in an aqueous medium is reported. The metal ion formed a 1:1 orange-red coloured complex with 2,4-dihydroxy benzophenone benzoic hydrazone (DHBPBH) at pH 10.0 showing an absorption maximum at 400 nm. The molar absorptivity and Sandell's sensitivity of the method are found to be 2.0 x 10(4)1/mol/cm and 0.007 mug/cm(2), respectively. Beer's law is obeyed in the range 0.7-7.0 mug/ml. Titanium, vanadium and molybdenum do not interfere. The extent of interferences by other ions is presented. The method is applied for the determination of cerium in simulated rock samples.

Malaria transmission during post-spray period of pirimiphos-methyl in Arunachal Pradesh.

Observations made for a period of four years from 1985 to 1988 on post-spray impact of pirimiphos-methyl (25 per cent Wp) on malaria vectors in Tirap district of Arunachal Pradesh showed that a low density (0.0 to 0.02 PMH) of Anopheles dirus was maintained in the areas sprayed with the insecticide at the dosages of 1 and 2 g/m2 from 1981 to 1984. The post-spray data (1985 to 1988) showed a reduction of 62.5 to 62.8 per cent in SPR, 55.6 to 64.7 per cent in SRF and 72.3 to 75.5 per cent decline in API as compared to baseline data of 1980 in areas sprayed with pirimiphos methyl.

Rapid and selective spectrophotometric determination of manganese in steels and alloys using resacetophenone oxime.

A sensitive spectrophotometric method is developed for the determination of manganese in aqueous medium. The metal ion forms a yellowish brown coloured complex with resacetophenone oxime (RPO) in ammonium chloride and ammonium hydroxide buffer of pH 10.5. The 1:1 complex shows maximum absorbance at 380 nm with a Beer's law range of 0.09-1.7 ppm. The molar absorptivity and the Sandell sensitivity are found as 2.5 x 10(4) l.mole(-1).cm(-1) and 0.002 mug/cm(2), respectively. The stability constant of the complex calculated by Job's method is 7.5 x 10(5). The interfering effects of various cations and anions are studied. The present method is applied to the determination of manganese in some steel and alloy samples.

Vector control through environmental management with special reference to India--approach prospectives.

The introduction of different types of pollutants like those from industrial effluence, bye-products from petro-chemical industries, pesticidal application, wastages of nuclear power industries, etc. is viewed seriously by the society. For the control of vectors of disease the adoption of environmental management is, therefore, imperative. The physical methods like drainage of excess and waste water, making water unsuitable for vector breeding by adopting various indigenous methods in vogue, the intra and inter-sectrol coordination and community based activities are identified as the basic approaches for achieving this goal. Minimising the potentiality of vector breeding through source reduction and water management is thought to be the simplest, cheapest and most permanent method. For the society having varying types of habitation and varying degree of habitational facilities like planned housing, water supply and disposal, sanitation and organized anti-vector measures, the adoption of environmental management to exercise check over vector population is a promising proposition. The suitability of such an approach has already been demonstrated by MRC, (ICMR), Delhi and V.C.R.C., Pondicherry. The implementation of these methods is to be initiated right from Primary Health Centre and district level onwards and community is to be motivated to the extent that the various methods of environmental management for vector control are adopted in the routine way of life. In the present article these ideas have been touched upon and various methods of environmental management described in brief. In addition what other Governmental agencies are required to do in order to effectively implement environmental management methods are briefly enlisted.

Blood Cholinesterase monitoring in spraymen involved in malathion spraying--a health protection measure.

The blood Cholinesterase (ChE) level of malathion in spraymen is continuously monitored through a "built-in warning system" existing under NMEP since the introduction of malathion spraying. The data available from the States of Maharashtra, Punjab and Gujarat revealed that, in spraymen of Punjab, the ChE level in 1988 and 1989 remained normal in about 99.8 per cent spray personnel, and in 1 out of 381 workers, the ChE level fell to 62.5 per cent during 1989. In Gujarat and Maharashtra, the normal level of ChE was maintained in nearly 88 and 98.4 per cent of spray personnel respectively during the spraying period. The ChE level fell to 62.5 per cent in 11.9 per cent of spray staff in Gujarat during 1987 and in 1.5 and 1.6 per cent persons during 1988 and 1989 respectively in Maharashtra. Only in three cases (0.07 per cent) out of 4,100 in Maharashtra showed depression in ChE to 50 per cent in 1988. In none of the above mentioned cases, there was any parasympathetic overstimulation or uneasiness, etc, even then they were withdrawn from spray and were given rest and where needed medical care.

Success of integrated methods of control of mosquitoes in India--a review.

The integrated methodology for the control of vectors of diseases as well as mosquitoes has become an accepted concept amongst the public health experts. The feasibility of adopting this approach in different situations for mosquito control as per field trials by various institutions has been reviewed in this article. This concept, to some extent, has been in vogue under National Malaria Eradication Programme since long in a practicable way. Satisfactory results have been obtained wherever this approach has been applied carefully. The applicability of the integrated control methodology is not difficult provided various methods to be integrated are chosen and utilized in a rational way. Thorough health education is a prerequisite to awaken the community to accept the methods as part and parcel of routine life.

Feasibility of controlling lymphatic filarial diseases through primary health care system.

A study was undertaken to explore the feasibility of treatment of clinical cases of filariasis by the Village Health Guides (VHG) and to assess the impact of different dose schedules by Diethylcarbamazine (DEC) on the frequency of acute attacks. It was observed that six days treatment with DEC at a dose of 500 mg daily was the most effective regimen in controlling recurrence of filarial attacks. The VHGs can serve the community in treating filarial cases with DEC.