Efficacy, acceptability and cost effectiveness of four therapeutic agents for treatment of scabies.

The aim of this study is to evaluate four drug regimens for treatment of scabies as regard their efficacy, acceptability and cost effectiveness. Two hundred cases with ordinary scabies were randomized into four groups. First group received ivermectin 200 µg/kg body weight single oral dose, repeated after one week. The second received benzyl benzoate 20% cream. The third received permethrin 2.5%-5% lotion, whereas the fourth group received 5-10% sulfur ointment. Topical treatments were applied for five consecutive nights. Patients were followed up for two weeks for cure rate and adverse effects. At the end of the study, permethrin provided a significant efficacy of 88% and acceptability in 100% of cases, but had higher cost to treat one case (20.25 LE). Ivermectin provided efficacy and acceptability rates of 84% and 96%, respectively, and had a cheaper cost (9.5 LE). Benzyl benzoate provided 80% for both rates and was the cheapest drug. Sulfur ointment provided the least rates, and it was the most expensive. Treatment choice will depend on the age, the general condition of cases, patient compliance to topical treatment and his ability to stick to its roles, and the economic condition of the patient.

The impact of insecticide-treated school uniforms on dengue infections in school-aged children: study protocol for a randomised controlled trial in Thailand.

BACKGROUND: There is an urgent need to protect children against dengue since this age group is particularly sensitive to the disease. Since dengue vectors are active mainly during the day, a potential target for control should be schools where children spend a considerable amount of their day. School uniforms are the cultural norm in most developing countries, worn throughout the day. We hypothesise that insecticide-treated school uniforms will reduce the incidence of dengue infection in school-aged children. Our objective is to determine the impact of impregnated school uniforms on dengue incidence. METHODS: A randomised controlled trial will be conducted in eastern Thailand in a group of schools with approximately 2,000 students aged 7-18 years. Pre-fabricated school uniforms will be commercially treated to ensure consistent, high-quality insecticide impregnation with permethrin. A double-blind, randomised, crossover trial at the school level will cover two dengue transmission seasons. DISCUSSION: Practical issues and plans concerning intervention implementation, evaluation, analysing and interpreting the data, and possible policy implications arising from the trial are discussed. TRIAL REGISTRATION: clinicaltrial.gov. REGISTRATION NUMBER: NCT01563640.

Permethrin decomposition after four month storage in the spray truck tanks during mosquito off season.

The concentrations of permethrin in the Aqua-Reslin formulation stored in the insecticide mixers/pumps, 16 ultra-low volume (ULV) truck-mounted spray tanks, and a stock container were sampled and analyzed by gas chromatography. The result showed that an average of 55.53% and 70.32% permethrin in Aqua-Reslin were decomposed in the ULV spray truck tanks and in the mixers/pumps, respectively, during the 4-month mosquito off-season. The degradation may directly result in economic loss. Also, the mosquito control efficacy may be compromised if the concentrations are inappropriate. The permethrin analytical method, economic cost, and degradation-prevention methods are discussed in this article.

Use of point-of-sale data to track usage patterns of residential pesticides: methodology development.

BACKGROUND: Residential-use pesticides have been shown to be a major source of pesticide exposure to people in the United States. However, little is understood about the exposures to household pesticides and the resultant health effects. One reason that little is known about home-use pesticide exposure is the lack of comprehensive data on exposures to pesticides in the home. One method to help ascertain the amount of pesticides present in the home is use of point-of-sale data collected from marketing companies that track product sales to obtain the volume of pesticides sold for home-use. This provides a measure of volume of home-use pesticide. METHODS: We have constructed a searchable database containing sales data for home-use permethrin-containing pesticides sold by retail stores in the United States from January 1997 through December 2002 in an attempt to develop a tracking method for pesticide. This pilot project was conducted to determine if point-of-sale data would be effective in helping track the purchase of home-use permethrin containing pesticides and if it would stand as a good model for tracking sales of other home-use pesticides. RESULTS: There are several limitations associated with this tracking method, including the availability of sales data, market coverage, and geographic resolution. As a result, a fraction of sales data potentially available for reporting is represented in this database. However, the database is sensitive to the number and type of merchants reporting permethrin sales. Further, analysis of the sale of individual products included in the database indicates that year to year variability has a greater impact on reported permethrin sales than the amount sold by each type of merchant. CONCLUSION: We conclude that, while nothing could completely replace a detailed exposure assessment to estimate exposures to home-use pesticides, a point-of-sale database is a useful tool in tracking the purchase of these types of pesticides to 1) detect anomalous trends in regional and seasonal pesticide sales warranting further investigation into the potential causes of the trends; 2) determine the most commonly purchased application types; and 3) compare relative trends in sales between indoor and outdoor use products as well as compare trends in sales between different active ingredients.

Cost-benefit analysis of ivermectin, permethrin and benzyl benzoate in the management of infantile and childhood scabies.

In the US, 6% sulfur in petrolatum has been the most frequently administered treatment for infantile scabies. It appears to be safe but there is no literature containing a large series of patients on which to base that determination. In the UK, benzyl benzoate is the approved product. Benzyl benzoate is rarely used in the US at the present time. 5% Permethrin is an excellent substitute and has many advantages. It appears to be quite safe in infants, although it is more expensive than other products. It remains present on the skin for several days, therefore protecting against reinfestation. Ivermectin is a systemic drug which is assumed to be safe in infants, although it requires repeated doses and does not protect against reinfestation. In the opinion of the author, 5% permethrin is the best treatment for scabies in infants and young children.

The cost-effectiveness of permethrin-treated bed nets in an area of intense malaria transmission in western Kenya.

This study compared the costs and effects of insecticide (permethrin)-treated bed net (ITN) use in children less than five years of age in an area of intense, perennial malaria transmission in western Kenya. The data were derived from a group-randomized controlled trial of ITNs conducted between 1996 and 1999. The annual net cost per life-year gained was 34 U.S. dollars and the net annual cost per all-cause sick child clinic visit averted was 49 U.S. dollars. After taking into account a community effect (protection from malaria afforded to non-ITN users who lived within 300 meters from users) these estimates decreased to 25 U.S. dollars and 38 U.S. dollars, respectively. This study provides further evidence that ITNs are a highly cost-effective use of scarce health care resources.

The household-level economics of using permethrin-treated bed nets to prevent malaria in children less than five years of age.

We measured the two-week household-level economic impact of insecticide (permethrin)-treated bed nets (ITNs) used to prevent malaria among children less than five years of age in Asembo, Kenya. The ITNs induced a two-week reduction of 15 Kenyan shillings (KSH) (0.25 U.S. dollars; P < 0.0001) in health care expenditures, but a statistically insignificant 0.5 day (P = 0.280) reduction in household time lost due to caring for sick children. The equivalent annual threshold cost was estimated at 6.50 U.S. dollars (95% confidence interval = 3.12-9.86). If the actual purchase price and maintenance costs of ITNs were greater than this threshold, then households would pay more than they would save (and vice-versa). Both seasonal effects and number of children per household had larger impacts than ITNs on health care expenditures and time lost from household activities. Health care expenditures by a household without ITNs and one child were only 32 KSH per two weeks (0.50 U.S. dollars; P = 0.002), leaving little opportunity for household-level, ITN-induced direct savings. The widespread adoption of the ITNs will therefore probably require a subsidy.

Field trial efficacy of Anvil 10+10 and Biomist 31:66 against Ochlerotatus sollicitans in Delaware.

Anvil 10+10 (hereafter Anvil) and Biomist 31:66 (hereafter Biomist) were applied by ground ultra-low volume (ULV) methods to determine the effectiveness of each formulation against Ochlerotatus sollicitans. Each formulation was tested at 50, 67, and 100% of respective maximum label dosage rates. Mosquitoes were exposed in cages on a 3 x 3 grid at distances of 30.5, 60.9, and 91.4 m. Mortality data were collected at intervals of 1, 4, and 12 h after treatment. No significant differences (P > or = 0.05) were found among formulations at applications of 100% of the label rate and no significant differences (P > or = 0.05) were found between Anvil applied at 100% of the label rate and Biomist applied at 50 and 67% of label rates. Ground ULV applications of Anvil at 100% label rate and Biomist at all tested rates were effective (> or = 95% mortality) adulticides. Applications of Anvil at 50 and 67% label rates were significantly less effective (P < or = 0.05) than applications of Biomist at equal percentages of the maximum label rate. Applications of Anvil at rates of 50 and 67% were not effective.