One Saturday in the spring of 1999, D.C. Mayor Anthony A. Williams convened a citywide "Rat Summit." It was the first of its kind in the nation.
Officially, the purpose was educational. Interested parties would have the opportunity to learn more about how they could help tame the city's severe rat problem. But, in fact, planners had a much more specific agenda in mind: to trumpet a new approach to rodent control that focuses on prevention rather than extermination.
Eighteen months later, the effects of the new initiative remain unclear. Mary Cronin, a D.C. resident and local activist who attended the summit, says the rat problem in her neighborhood "comes and goes." But whether prevention turns out to be the answer or not, cities all over the country, from Boston to New York to Chicago, are trying it. Increasingly, they are directing their attention and resources toward thwarting rodents instead of killing them. Some experts, in fact, worry that the swing toward prevention may have gone too far, and that the practice of eradicating the pests by poison shouldn't be cut back precipitously.
This is a time of increased concern about the rodent problem in big American cities. There are several reasons why. Mild winters in many places over the past few years have created ideal conditions for rats to flourish. Healthy budgets have made funding available. And most important, the number of construction projects in many urban centers has soared. When old buildings are demolished or new sewer and water lines are installed, rats are rendered homeless and go in search of new shelter. In Boston, for example, the city's massive reworking of its highway system has sent rats scurrying en masse. The city and the Massachusetts Turnpike Authority now have five full-time workers assigned to rodent control.
Rats aren't just ugly and frightening--they continue to earn their long-standing reputation as carriers of disease. During this century, they have caused two major outbreaks of bubonic plague in the United States. In addition, they spread hantavirus and rat-bite fever (the latter of which frequently afflicts the homeless and drug addicts).
Even though modern sanitation and antibiotics have stemmed plague, it still occurs. According to the federal Centers for Disease Control and Prevention, 362 cases were identified between 1944 and 1993. Nearly all of them were found in just four states--Arizona, California, Colorado and New Mexico--and generally in places where development had spread to once rural areas. The most recent urban case, notes the CDC's Kenneth Gage, occurred in 1993, when a roof rat was found to have plague in a wealthy subdivision outside Dallas.
Scientists don't really know why infected fleas are concentrated in the southwestern states. They warn, however, that plague could reappear in cities almost anywhere in the country. The brown Norway rat, also called the wharf and sewer rat, is more common in the East and Midwest than in the South or West.
But the bottom line is that rat-borne diseases aren't a regional problem or a poverty problem. They are a problem of density. As Bruce Colvin, one of the foremost experts on rat control, says, "where you have more population density and more crowding and more restaurants and older infrastructure, there are more rats."
Not surprisingly, there is an array of urban rat-control programs. Some cities, where little evidence of infestation exists, simply give residents and business owners instructions and poison to kill rats on their own. Others keep only a handful of exterminators on the payroll.
But in the past few years, the prevention model has won a steady following. Bruce Colvin rose to prominence in Boston by overseeing the rat-control efforts of that city's "Big Dig" transportation project, which he led from 1989 to 1998. Colvin's approach was very aggressive: Contractors were required to empty trash on their sites every day; there was weekly reporting of messy sites, and fines of up to $1,000. Colvin has advised many other cities to adopt a similar strategy.
Meanwhile, in Chicago, Mayor Richard M. Daley launched an anti-rat task force in 1994, aiming to toughen the city's sanitation-disposal laws. To that end, he targeted restaurants and businesses whose garbage bins overflowed. "Rats just don't fall out of the sky," says Al Sanchez, commissioner of Chicago's Department of Streets and Sanitation. "They're usually where the food source is. If you cut off the food source, they're not able to exist like they once did. They'll start attacking each other." This July, an ordinance went into effect in Chicago requiring owners of residential and commercial properties that generate more than 50 cubic yards of trash a week to buy trash compactors."We've found that containerization is the best way," Sanchez says.
The District of Columbia program is largely modeled after Chicago's approach. Starting this fall, D.C. officials are slapping fines of $1,000 on restaurant and business owners who fail to keep their property clean, and $75 on residents who are careless with such things as pet food and bird droppings. Commercial-property owners can be required to schedule more regular garbage pickups.
New York is doing something similar. James Gibson, hired this spring as the Big Apple's "rat czar," previously worked on rodent control at the Chicago Housing Authority. One of his first moves in New York was to control the presence of garbage bags on city streets, where they have been ubiquitous for decades.
To some rat experts, however, there is a downside to the prevention model--chiefly its neglect of the importance of extermination. Greg Glass, of the School of Hygiene and Public Health at Johns Hopkins University, argues that cities need to have many more exterminators per capita than they now employ if they want to tame their rat populations. By Glass' standard, Washington and New York are failing. D.C. (with a population of 523,000) has only 11 full-time exterminators, and New York (with 7.4 million residents) a mere 23. "There's nothing you can do with that number of people," Glass laments. "You might as well close the shop."
Any extermination strategy is complicated by the fact that rats gradually become resistant to poisons. Genetically diverse, they build up tolerance to any batch of poisons discouragingly quickly. But in Glass' view, this isn't a reason to abandon extermination--it's a reason to intensify it. Where exterminators could get away with baiting an alley once every six months, Glass says, they now need to do it four or five times to get the same effect.
Other specialists have reached similar conclusions. William Jackson, a biologist at Bowling Green State University who helped create the first-generation of modern anti-coagulant rat poisons in the 1950s, says that rats are already becoming resistant to the second generation of such poisons in Europe. "It's very well documented in England," he says. "Usually, we're 10 years behind in this phenomenon." While Jackson is a believer in prevention, he insists that extermination is still an essential part of any successful rat-control program. "Rodenticides speed up the process," he says.
In the late 1960s, the U.S. government was a major player on the rat- control front, helping to subsidize a "war on rats" in many cities. The Centers for Disease Control spent $169 million on the program between 1969 and 1980, while states and cities chipped in an additional $193 million. But the federal program ended in the 1980s, and Congress has not shown any willingness to fund new extermination efforts. This year, U.S. Senator Dick Durbin of Illinois requested $350,000 for rodent-control research as part of a year-end spending package, but it was turned down.
So cities are pretty much on their own, and they seem eager to try practically any new idea that comes along, whether it emphasizes prevention, old-time extermination methods or simply turning up the volume of concern. This past summer, New York newspapers reported that thousands of rats had nested near the Baruch Houses, a public housing complex on Manhattan's Lower East Side. There was no quick way to get rid of them, but there was an opportunity for some public education: Mayor Rudolph Giuliani convened a citywide prevention task force, and called on officials in his agencies to meet weekly to identify sites around the city besieged by rats.
"I would say that our problem is certainly one that requires a lot of attention," says Gibson, the newly hired anti-rat boss. "The administration is putting a lot of attention to solving it." But, like many other officials, he warns that it could be years before major progress occurs.