Combating the Zika virus
Sir, – It surprises me that the media do not give more attention to the realities facing global attempts to combat diseases such as Zika.
The current concerns regarding the threat of Zika virus is the belief that the World Health Organisation have either the resources or the capacity to successfully contain the current epidemic.
In the media we are encouraged to believe the WHO can successfully eradicate these Aedes mosquitoes, the vector of Zika, through chemical and biological means, despite the fact that these eradication campaigns have been largely unsuccessful for over a 100 years.
According to some reports, the scientists have developed a mosquito strain which produces up to 95 per cent males, thereby limiting the numbers of females which are involved in transmission.
But female mosquitoes can produce around 500 eggs in one brood of which there may be up to 10 in her short life. With a lifecycle of around two weeks and favourable tropical conditions, the progeny from one female reaches unimaginable numbers. The rapid turnover of generations enables a genetic fine-tuning that facilitates not only species survival but also new strains of modified mosquitoes.
Mosquito transmitted diseases such as malaria, dengue, yellow fever and currently Zika, pose serious dangers to human health.
However scientific interventions at environmental and ecological levels, particularly when done under the glare of the media and the pressure for quick results, need scrutiny lest they exacerbate the situation rather than tame this highly successful ancient insect species.
Incidentally, the most effective protection for humans against mosquito breeding sites is through improving social and economic conditions; something that seems unlikely to happen soon for the poor of the developing world, where 90 per cent of the disease transmission takes place.
– Yours, etc,
Dr VINCENT KENNY