Over the past few days Yolo County has exploded into colour, as millions of bright yellow butterflies, some pale like rose petals, some crisp and golden like autumnal leaves, have emerged from their cocoons into the sunlit fields. They have been joined by a sudden burst of erratic dark red dragonflies, which dart about inquisitively with all of the elegance of a supermodel emerging from a Soho nightclub at 4am with a washed-up occasional singer. Their arrival has coincided with the Delta Breeze, the cooler air that has finally ended the recent hot spell, and all is well again for the people of Davis. Or it would be if it wasn’t for the unwelcome appearance of another insect, the mosquito, the bug for whom all these screen doors was made. However it isn’t the mosquito itself that has everybody worried, it is what it carries – the West Nile Virus, which has been discovered on specimens at the UC Davis Arboretum, and many other watering holes besides.

Since arriving poor and hungry in New York in 1999, the West Nile Virus has spread across the United States, eventually reaching California in the summer of 2003. As with all media-driven viruses, cases of West Nile have received far more attention than run-of-the-mill killers such as flu. Needless to say, people are worried, and this week local authorities decided that the only way to combat the mosquitoes was, as seems to be the answer to everything these days, systematic air strikes. No, they won’t be firing rockets into ponds – they are planning two nights of chemical warfare, spraying pesticide from light planes over the entire county. The mosquitoes have not yet released any statement of how they will react to this threat, but expect some serious last-minute biting. So how have the locals, the champions of organic farming, reacted to the prospect of a mass-spray?

Many of the residents are unhappy. One group, Stop West Nile Spraying Now, claims that the decision to spray has more to do with politics than science (davis enterprise). A UC Berkeley study has suggested that, while the spray itself has very little effect on public health (according to officials, at least), it can react with other pesticides to make them far more toxic. All of this may well have economic ramifications for the local organic growers. However there does appear to be a fair bit of support for the spray, largely fuelled by fears of the virus attacking older and weaker folk. While most people who are affected have little or no symptoms, enough people become sick to make people sit up and notice; worse, it is believed that even when death does not occur, some neurological effects may be permanent (CDC).

Of course, West Nile isn’t the only thing keeping people up at night. The impending cloud of Bird Flu has led to organizations planning for the complete breakdown in public services that such an epidemic might bring, while the Yolo County website warns people about the existence of Rabies among local species of bat. Not to mention cautioning hikers about the dangers of Bubonic Plague caught from animals in the Sierra. If the heat don’t kill ya, and the terrorists don’t get ya, and the earthquakes and fires and floods don’t finish you off, the bats and the birds and the bugs and their bites will.