During the summer of 2016, an epidemic swept across the Western Hemisphere. We’re not referring to the Zika virus – no, not exactly – but the widespread panic among members of the population who feared that Zika would cause a generational tidal wave of birth defects.

Months later, that tsunami of microcephaly cases has yet to materialize (apart from the initially reported scourge in certain regions of Brazil), and the associated fear seems to have abated somewhat.

Here in the Cayman Islands, last summer’s unwarranted terror over Zika was joined by a separate, but associated, panic – of the pilot deployment of genetically modified mosquitoes in West Bay. With the winter season now standing between Cayman and the GM mosquito release, it also appears to be the case that “everybody’s worst nightmares” about so-called “Franken-mozzies” have also failed to materialize.

Here are the interim results of the program by British biotechnology firm Oxitec, according to Cayman’s Mosquito Research and Control Unit:

The number of Aedes aegypti eggs collected in traps in the treatment area was 88 percent less than the designated “non-treatment” area nearby.

The proportion of Oxitec mosquito offspring (which contain biological fluorescent marking) among Cayman’s wild Aedes aegypti population has increased to an average of 94 percent during the last two months.

In other words, the evidence indicates that Oxitec’s program is producing successful results, similar to the company’s earlier field releases in Grand Cayman’s East End, as well as in Brazil and Panama.

As we’ve said before in this editorial space, the Zika virus is not – and never was – the pre-eminent threat to public health in Cayman. The moniker of “Public Enemy Number One” belongs to the carrier of Zika and other dangerous diseases, that is, the Aedes aegypti mosquito.

We re-emphasize that one of our government’s primary goals (which would be the Cayman equivalent of U.S. President John F. Kennedy’s “Moon shot”) should be the utter eradication of Aedes aegypti from our beloved isles. We recognize that this ambitious mission cannot be accomplished with a single measure or technology, such as Oxitec’s mosquitoes, but would necessitate a sustained assault against Aedes aegypti on all possible fronts, including ground-based spraying and aerial bombing by MRCU trucks and aircraft, as well as a comprehensive public education campaign to enable and encourage residents to rid their households of this “domestic” nemesis.

For example, some critics of the Oxitec program put forth what they believe to be better alternatives, such as releasing mosquitoes that have been infected with the Wolbachia bacterium, which has been shown to limit mosquitoes’ ability to develop viruses such as Zika, dengue and chikungunya.

If asked to choose between conventional tactics, Oxitec’s approach or the Wolbachia method … Our answer is: “Yes. All of the above.”

Thankfully, the dangerous mosquito population remains low in the Sister Islands, but Grand Cayman has five districts that are full of Aedes aegypti in urgent need of elimination. With the baseline assumption that we take into account the chances of success versus the risks to humans and the natural environment, our attitude is, anything that will work, let’s do it; anything that might work, let’s try it.

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  1. Has there been any analysis for change in resistant bacteria since the GM mosquito release?

    Key haven Florida voted the release down as the company has a process that begs the question of producing resistant bacteria in their bug factory and the adult GM mosquitoes possibly spreading these germs to people’s home, cars, pets etc. the company has not tested their adult insects for resistant bacteria. Considering the explosion of antibiotic resistant super bacteria illnesses for which the United Nations declared an emergency meeting in September, a large percentage of the local Key West area physicians signed a petition requesting culturing the adult-to-be-released GM mosquito and any resistances factored into any release. We have yet seen the data, the doctors have requested a delay in release until the data is made available by a third party lab