To Beat West Nile, Kill The Carrier

It is common in Washington’s parks these days to see mothers rubbing their children’s arms, faces and legs with wipes pulled from brightly coloured plastic containers. Three years ago, these would have been anti-bacterial cleansers, which were then the latest thing. These days, however, the damp squares of fabric are saturated instead with bug repellent.

Mothers are suddenly less worried that little Johnny’s hands might be grubby than that he’ll get West Nile Virus. The United States is in the midst of its worst ever outbreak of the disease. According to the Centres for Disease Control, the virus has sickened 1,641 people this year and killed 80. From 1999 through 2001, there were 149 cases and 18 deaths.

However regrettable to victims, families and friends, 80 deaths do not amount to a major public health calamity in a population of 280 million. But it’s equally innumerate to console oneself with little factoids such as that you are statistically more likely to be killed by a falling bale of hay than by the mosquito-borne virus. For most of us, who never get near a bale of hay, the chance of that bizarre agricultural demise is zero. But almost all of us get mosquito bites. Indeed, Ontarians commented all summer that there were more mosquitoes this year; there was much scratching, slapping and cursing at barbecues and garden parties.

Now, the first victim to have contracted West Nile Virus in Canada has died. The 70-year-old from Mississauga was one of some 16 people infected in Ontario, and there are several more in Quebec. The disease has come north from the eastern United States, particularly New York, but it has also spread to California and as far north as Thunder Bay. So it’s continent wide and here to stay.

Here to stay unless, that is, North American society shakes off its romantic environmentalist reverie and ends its antipathetic fixation on pesticides. Like a dog with its favourite bone, we refuse to let go. Polls suggest that three-quarters of Americans are "extremely or very concerned" about pesticide pollution. With great callousness, the West has even bullied African nations to stop safe and effective use of DDT, despite the fact that between one and two million people die of malaria on that continent every year. Notwithstanding a wealth of compelling scientific evidence to the contrary, we have remained convinced, ever since Rachel Carson’s told-us-so Silent Spring (1962), that we’re surrounded by synthetic killers.

Well yes, they are synthetic killers — but the things they kill are insects, not humans. The U.S. Environmental Protection Agency, which cannot plausibly be regarded as underestimating environmental risk, sets safety standards so cautiously that a three-year-old child could without harm stand for 20 minutes enveloped in a cloud of the mosquito killer, malathion, being sprayed at legal concentrations from a fogging truck.

Yet the manufacturer, American Cyanamid Corp., has decided not to go to the trouble and expense of re-registering malathion, which is also used in Canada, as EPA regulations require and has sold the product rights to a Danish firm that may or may not choose to jump through the U.S. regulatory hoops. If not, an effective weapon against disease vectors might soon be lost in North America; three cheers for environmentalism.

It should be remembered that the term "tropical disease" does not describe the natural range of the scourges to which it is applied — thousands died of malaria digging the Rideau Canal, not just the Panama Canal — but is, rather, a terminological tribute to the way rich countries protected themselves from many diseases. They did it with pesticides.

Ontario’s health ministry is considering spraying against mosquitoes next season. Parents, who do not mind that chemicals be used at safe levels to protect children in swimming pools, can have no well-founded objection to the safe elimination of mosquitoes using pesticides.

It’s not that West Nile Virus has created an emergency — although the oft-repeated claim that only very young and very old people are at risk is as unpleasant as it is factually inaccurate — but that there is no environmental health reason not to spray. The EPA, World Cancer Research Fund and even the Canadian Cancer Society all acknowledge that pesticides pose a vanishingly small health risk.

In his myth-shattering book, The Skeptical Environmentalist, Bjorn Lomborg calculated that the formaldehyde level in a typical house makes staying home for 14 hours 260 times more carcinogenic than consuming the average intake of ETU, the most toxic pesticide in use today.

It should not take a new disease like West Nile to prompt mosquito eradication — we should get rid of them anyway because they’re the most irritating creatures in creation. Much more than the mosquitoes, though, it would be wonderful to eradicate the myths about pesticides — but they’ve been sprayed with facts so often they’ve become immune.