Residual Efficacy of Insecticides Sprayed on Different Types of Surfaces Against Leishmaniasis and Filariasis Vectors in Egypt.

Determination of the residual activity of insecticides is an essential component in the selection of an appropriate insecticide for indoor residual spraying operations. This report presents the results of a laboratory study to evaluate the residual bio-efficacy of four insecticides sprayed on the most common house-wall surfaces that occur in Egypt (wood, mud, and cement) against Phlebotomus papatasi (Scopoli, 1786) (Diptera: Psychodidae) and Culex pipiens Linnaeus, 1758 (Diptera: Culicidae). In total, 28,050 P. papatasi females and 31,275 Cx. pipiens females were subjected to the WHO cone bioassay. Effective and extended control (≥80% mortality) was produced by lambda-cyhalothrin on indoor wood and cement surfaces. Lambda-cyhalothrin effectively controlled (>80% mortality) P. papatasi and Cx. pipiens for 10 and 12 wk postspray on wood surfaces, respectively. Deltamethrin effectively controlled Cx. pipiens for 8 wk on indoor wood, mud, and cement surfaces. Indoor and outdoor-kept surfaces treated with permethrin and malathion provided negligible efficacy against P. papatasi and Cx. pipiens. Phlebotomus papatasi was better able to survive bioassay exposure than Cx. pipiens against all insecticides investigated. The role surfaces might play in inhibiting IRS-based vector control endeavors in rural areas in developing countries was highlighted in this study. The current insecticide labeling system that includes both sand flies with mosquitoes under the same dosage category should be revised periodically.

Epidemiology of Cutaneous Leishmaniasis Outbreak, Waziristan, Pakistan.

During 2013-2015, prevalence of cutaneous leishmaniasis in war-affected Waziristan areas was 3.61% by PCR. Youths (1-15 years of age) were more susceptible. Internal transcribed spacer 1 PCR followed by restriction fragment length polymorphism analysis identified Leishmania tropica in 215 samples and Leishmania major in 6 samples.

Crimean Congo Hemorrhagic Fever Virus and Alkhurma (Alkhumra) Virus in Ticks in Djibouti.

Crimean Congo hemorrhagic fever virus and Alkhumra virus, not previously reported in Djibouti, were detected among 141 (infection rate = 15.7 per 100, 95% CI: 13.4-18.1) tick pools from 81 (37%) cattle and 2 (infection rate = 0.2 per 100, 95% CI: 0.0-0.7) tick pools from 2 (1%) cattle, respectively, collected at an abattoir in 2010 and 2011.

Sticky bottle traps: a simple and effective method for collecting adult phlebotomine sand flies from rodent burrows in a Leishmania-endemic region of Egypt.

We describe a simple, economic, and effective method for constructing sticky bottle traps that can be used to capture adult sand flies from rodent burrows. Although sand fly surveillance activities often employ light- or CO2-baited traps, sticky papers secured to a post or placed on the ground can also be used. However, in arid environments, sand and other debris often collect on the sticky surface, reducing trap effectiveness, capacity, and a means for rapid discrimination and enumeration of adult specimens. Herein, a procedure for constructing sticky bottle traps is provided, as well as preliminary results from a recent sand fly field survey utilizing this device.

Effects of ivermectin on blood-feeding Phlebotomus papatasi, and the promastigote stage of Leishmania major.

Ivermectin (IVM) is a chemically modified macrocyclic lactone of Streptomyces avermitilis that acts as a potent neurotoxin against many nematodes and arthropods. Little is known of IVM's effect against either blood-feeding Phlebotomus sand flies, or the infective promastigote stage of Leishmania transmitted by these flies. We injected hamsters subcutaneously with two standard IVM treatments (200 and 400 µg/kg body weight) and allowed cohorts of Leishmania major-infected Phlebotomus papatasi to blood-feed on these animals at various posttreatment time points (4 h, 1, 2, 6, and 10 days). Infected and uninfected sand flies that bit treated and untreated hamsters served as controls. Serum levels of IVM in low- and high-dose-treated hamsters were determined at the five time points. Sand fly mortality following blood feeding was recorded at 24-h intervals and, in relation to IVM treatment, was time and dose dependent. Mortality was most rapid and greatest among infected flies that fed nearest to time of dosing. Mean survival of infected sand flies after feeding on untreated hamsters was 11.5 days, whereas that of infected sand flies that fed 4 h, 1 day, or 2 days posttreatment on high-dose-treated hamsters (400 µg/kg) was 1.6, 2.1, and 2.7 days, respectively. Infected and uninfected sand flies that blood fed 6 days following low-dose IVM treatment (200 µg/kg) still experienced significantly greater mortality (p < 0.02) than controls. Promastigotes dissected out of surviving flies that fed on IVM-treated hamsters showed typical motility and survival. Moreover, 21.7% of IVM-treated hamsters developed lesions after being fed upon by infected sand flies. L. major promastigotes appeared to be tolerant to ng/mL blood levels of IVM that caused significant mortality for up to 10 days posttreatment in blood-feeding P. papatasi.