Delivering biting public viewpoints can sometimes sting -- always a risk when writing an opinion column. Still, I assume that risk and straightaway proclaim: I hate mosquitoes.
I know some readers will oppose my view. But I'll bet that, unlike me, they don't transmute into one huge welt, from head to toe, after a single stinging encounter with a mosquito.
That they've never slapped themselves unconscious trying to kill a maniacally buzzing mosquito circling their ears. That perhaps they're behind in their reading, lacking updated news about West Nile virus in recent reports from the Centers for Disease Control and Prevention.
We currently face an outbreak of mosquito-borne WNV infection in the U.S. As of last Tuesday, at least 1,590 people have been infected by WNV so far this year, and 66 have died. Californians have accounted for 44 of those infections and one fatality.
Additionally, the number of confirmed WNV cases has risen so precipitously within recent weeks as to qualify the current outbreak as the worst our country has experienced since WNV first appeared within the U.S. a mere 13 years ago.
No one really knows why WNV seems to have become so vigorous recently. Some health officials point to observed unseasonable climate alterations that favor the ecosystem of the loathsome disease-carrying mosquito: an unusually mild winter, followed by an early spring and remarkably hot summer. In support of their view,
Conventionally, scientists have claimed that about 80 percent of all human WNV infections go unnoticed and undocumented because most people don't feel sick or obtain medical care for minor symptoms. We only know about their infections retrospectively, by using blood tests to screen populations of people for evidence of prior infection.
In the remaining 20 percent of WNV infections, people may seek a doctor's attention for symptoms like fever, body aches, headache, rashes, swollen lymph nodes, nausea and vomiting. If they are diagnosed with WNV, public health departments are dutifully notified. Clearly, only a small minority of all WNV infections makes it into the official public record.
The main concern about WNV involves the risk of a serious neurological complications caused by inflammation of the brain (encephalitis) or its surrounding tissue (meningitis).
This "neuroinvasive" complication occurs in approximately 1 percent of human infections, and it can manifest with high fevers, neck stiffness, headaches, confusion, seizures, vision loss, tremors, and paralysis.
The neurological complications can become permanent, and between 4 percent 18 percent of all people with neuroinvasive disease die.
Against the backdrop of this conventional wisdom, many worried observers question why fully 56 percent of recently confirmed cases in the U.S. have been categorized as neuroinvasive. They ask whether WNV has mutated into a more dangerous form. But the CDC reassuringly suggests that that number must be taken in context.
When considering all cases of WNV infection that actually occur -- not just the sickest cases reported to public health departments -- the percentage of people with neuroinvasive complications shrinks dramatically toward conventional expectations.
The WNV outbreak serves to remind us about the vital importance of public health agencies like the CDC, the California Department of Public Health, and local mosquito control agencies. In times like these, they form a powerful SWAT team protecting public safety.
We are also reminded about personal agency and civic responsibility -- the steps we can take as individuals to protect ourselves and our communities from WNV-carrying mosquitoes. Such precautionary strategies assume great importance because there is no specific treatment for human WNV infection, and no vaccine to prevent it.
The chief strategy for controlling mosquito populations stems from a central premise: That anything capable of containing stagnant water for even several days can serve as a breeding ground for mosquitoes. It can be a real eye-opener to check and remedy your surroundings for these 'skeeto motels. For example, I was surprised to find pockets of old rainwater in the tarps I had used to weather-protect garden tools. And, sadly, I also discovered the new menace of a garden gnome who held a glass column that collected and measured rainfall.
Public health officials recommend explicit search for stagnant water associated with clogged rain gutters; flowerpots, barrels, and old tires strewed about the yard; leaky faucets; street gutters and storm drains; swimming pools; birdbaths and fish ponds.
They also recommend that people take measures to reduce their risk of being bitten by mosquitoes. That includes limiting outdoor activities during dusk and dawn when mosquitoes are most active, and protecting your skin with mosquito repellent and protective clothing. Mosquitoes should be made most unwelcome in the home, too, by keeping window and door screens in good repair.
Finally, public health agencies encourage people to report dead birds because, among all animals, birds are most likely to sicken and die from the bites of WNV-carrying mosquitoes; they also serve as the main source of infection for mosquitoes, feeding a vicious cycle of WNV spread. Locating hot-spots of WNV activity through bird reporting helps public agencies focus their mosquito abatement efforts where they are most needed. You can report dead birds online (www.westnile.ca.gov) or by phone (toll-free, at 1-877-WNV-BIRD).
Act today. Don't let this information come back to bite you.
Kate Scannell is a Bay Area physician and syndicated columnist. Her recent novel is "Flood Stage."