El Salvador - Adaptation of Aedes Aegypti confirmed: they can breed in dirty water

[Gert van der Hoek]

El Salvador: Dangerous Mutation of Aedes Aegypti Discovered

San Salvador, Oct 30 (Prensa Latina) Salvadoran scientists discovered an alarming mutation of the Aedes Aegypti mosquito, able to reproduce in dirty water and not exclusively in clean water, as was believed so far.

This discovery was confirmed by the Center for Health Research and Development (CENSALUD) at the University of El Salvador (UES) and recognized by the Deputy Minister of Health, Eduardo Espinosa, reported La Prensa Grafica newspaper.

This mutation could cause an increment in new dengue cases, in the light of the possible reproduction of the mosquito in the stagnant waters left by the rains that fell from Oct. 10 to 19.

The Aedes Aegypti has muted its DNA due to environmental factors, which are present in El Salvador, explained Stanley Rodriguez Aquino, a researcher at the Censalud-UES.

preansa latin

[Gert van der Hoek]

Re: El Salvador: `Dangerous Mutation of Aedes Aegypti Discovered?

machinetranslation

Saturday, October 29, 2011

Aedes can breed in dirty water

Research Center for Health Research at the University of El Salvador indicates that the mosquito transmits dengue now is breeding in dirty water.

The mosquito transmits dengue, Aedes aegypti, has undergone a transformation and allowed to reproduce only in clean water. Currently you can also do in dirty water, confirmed the Centre for Research and Health Development at the University of El Salvador (CENSALUD-UES) and recognized by the Deputy Minister of Health of El Salvador , Eduardo Espinoza.

This factor could cause an increase in dengue cases in the coming days due to the breeding of larvae in stagnant water remaining in the flooded areas after 10 days of rain.

Mutation of Aedes aegypti responds to changes in their DNA by environmental factors, in this case what has El Salvador : the heat and rain, said Stanley Aquino Rodriguez, a researcher CENSALUD-UES.

"Depending on the environment, mosquitoes adapt. The same situation influences to generate resistance to insecticides have no effect on them and now they can play in dirty water, "said researcher alma mater.

The conclusions are supported CENSALUD-UES after collecting samples of larvae in puddles and where outbreaks of dengue have been found.

At the same time, Rodriguez Aquino said they have made in communities of mosquitoes analysis to verify the situation.

At the moment there are no changes reported in the Aedes albopictus, the other transmitter.

Deputy Health Minister said the changes that have taken the mosquito transmits dengue are also noticeable in the reduction in their reproductive cycle, which used eight to 12 days and is now carried out in six to 10 days.

"True, the mosquito has learned to breed in dirty water, but we must not forget that 70% of the total dengue cases reported in the country today have been in urban areas. These are the big cities such as San Salvador, Santa Tecla, Sana Ana, San Miguel and Sonsonate. That does not mean you should let your guard down, and today more than ever we need the support of the population, "Espinoza justified.

The change in the mosquito transmits dengue is not unique to El Salvador . In 2010, the Ministry of Health of Mexico reported the same situation, as reported at that time the authorities of that country.

Read more: la prensa grafica

[Gert van der Hoek]

Re: El Salvador: Mutation of Aedes Aegypti Discovered

Neotrop Entomol. 2010 Nov-Dec;39(6):1016-23.

[The effect of water quality in the life cycle and in the attraction for the egg oviposition of Aedes aegypti (L.) (Diptera: Culicidae)].

[Article in Portuguese]

Beserra EB, Fernandes CR, Sousa JT, Freitas EM, Santos KD.
Source
Depto de Biologia, Univ Estadual da Paraíba, Campina Grande, PB, Brasil. ebarbosa@uepb.edu.br

Abstract
The present research aimed at evaluating the influence of the water quality in the life cycle and attraction of Aedes aegypti (L.) females to oviposit using different sources of water (raw sewage, effluent of UASB reactor, effluent of polishing lagoon, effluent of anaerobic filter, rain water and de-chlorinated water).

The immature development time and survivorship were evaluated on a daily basis in two distinct feeding systems (with and without food). The quality of the water was shown to affect the egg and larval stages, but not the pupal or the adult. In the absence of food, no development was observed in rain water and de-chlorinated water.

Immature development was faster in water sources from raw sewage, although with the lowest survivorship (37.3&#37. Free-choice tests indicated that females preferred to lay most of their eggs on water collected from the effluent of a UASB reactor, achieving the highest oviposition activity index (OAI) of 0.57. In non-choice tests, females laid larger batches of eggs in water collected from anaerobic filters (204.8 eggs), with the lowest number of eggs being laid on de-chlorinated water (37.3 eggs).

It can be concluded that A. aegypti does not demonstrate any particular preference to lay eggs on clean water.

This has serious implications for developing strategies to manage populations of this important vector in urban areas as it was shown to lay eggs and successfully develop on several different sources of water.

PubMed