Entomopathogenic fungi for the control of larvae and adults of Aedes aegypti (Diptera: Culicidae) vector of dengue, chikungunya and Zika viruses in Mexico.

Objective: To assess larvicide and adulticide activity of different native strains of fungi on Aedes aegypti.

Materials And Methods: Third instar larvae were exposed for 72 h at a concentration of 1x108 conidia/ml of 15 fungi; only fungi that significantly affected the larvae were evaluated against the adult phase at a concentration of 2x1010 conidia/ml. Mortality readings were performed at 24, 48, and 72 h for larvae, and every day to 30 days for adults.

Evaluation of commercial aerosol insecticides for control of Aedes aegypti susceptible or resistant to pyrethroids.

Objective: To evaluate indoor use of commercial aerosols for dengue vector mosquito control, and estimate the number of treatable houses per can.

Materials And Methods: Four aerosol products containing combinations of pyrethroids (two containing propoxur and one containing synergists too), were evaluated with mosquitoes in a room of a Tapachulastyle house. Eight cages containing 20 insecticide susceptible or resistant females were hung from tripods, another set was placed in sheltered areas of the room.

Determination of insecticides' lethal concentrations and metabolic enzyme levels in Triatoma dimidiata.

Objective: The feasibility of the use of WHO impregnated paper and biochemical assays to determine lethal concentrations (LC50 and LC99) and insecticide metabolic enzyme levels of Triatoma dimidiata.

Materials And Methods: LC50 and LC99 were calculated with WHO papers impregnated at different concentrations of malathion, propoxur and deltamethrin; the percentage of insensitive acetylcholinesterase (iAChE); and the levels of esterases, glutathione S-transferases, and monooxygenases in laboratory nymphs of the first stage (5 to 7 days), were undertaken using the WHO biochemical assays.

Results: Respectively the LC50 and LC99 μg/cm2 obtained for malathion were 43.

[Indoor thermal fogging of the mixture of flupyradifurone and transflutrin on Aedes aegypti mosquitoes susceptible and resistant to pyrethroids in southern Mexico].

Objective: To evaluate the efficacy of thermal fogging of a mixture of flupyrafirudone (26.3 g/L) and transfluthrin (52.5 g/L) against dengue, Zika y chikungunya Aedes mosquito vectors.

Effectiveness of indoor ultra-low volume application of Aqua Reslin® Super during an emergency.

Indoor ultra-low volume (ULV) applications of Aqua Reslin Super (Permethrin + s-bioallethrin) were carried out using portable Solo Port 423 sprayers in an urban area of Reforma, Chiapas, Mexico. Sprayers were calibrated to discharge a flow rate of 110 ml/min with a dose range of approximately 0.55 to 0.

Prevention of the transmission of Chagas' disease with pyrethroid-impregnated materials.

Interrupting the transmission of Chagas' disease using insecticide-treated materials could be a cost-effective option, particularly for sylvatic vectors, which enter houses at night. A randomized trial was undertaken that included all houses in two communities in regions endemic for this disease, one in Venezuela (50 houses) and one in Colombia (47 houses). After a baseline study (including a short questionnaire survey, entomologic assessment, and Chagas' disease serology), each household was randomly allocated to either the intervention group, which used pyrethroid-impregnated bed nets, or the control group, which used unimpregnated bed nets.

Wash resistance of insecticide-treated materials.

The effectiveness of insecticide-treated materials (ITMs) for malaria control is reduced by washing them. This research in Colombia and Bolivia investigated the resistance of different insecticide formulations and, in particular, a commercially available impregnated bednet (PermaNet) which provides chemical protection for the insecticide. The fabrics studied were all polyester; the pyrethroids used for impregnation were deltamethrin (tablet and suspension concentrate both at 25 mg/m2 target dose), lambdacyhalothrin (capsule suspension at 15 mg/m2; laboratory study only), alphacypermethrin (suspension concentrate at 40 mg/m2) and, in the case of PermaNet, deltamethrin (55 mg/m2).

Malaria control reinvented: health sector reform and strategy development in Colombia.

The consequences of health sector reforms on control of malaria were analysed using Colombia as an example. One of the most complex health sector reform programmes in Latin America took place in the 1990s; it included transferring the vertical vector-borne disease control (VBDC) programme into health systems at state and district levels. A series of studies was undertaken in 1998-2000 at the national level (Ministry of Health Study), at the state level (Departamento Study) and at the health district level (District Study) using formal and informal interviews among control staff and document analysis as data collection tools.