UV shelter study: Sunny with few conversions
Or, decorating quirky spaces with killer lights
Preliminary data are coming in from a six-city study of ultraviolet (UV) germicidal radiation in homeless shelters. If anything, the results suggest that from the researchers’ pont of view, something’s working a bit too well.
Counting sites with both real and placebo lights, there have been only two skin-test conversions recorded so far, making it tough to measure differences between intervention and control settings.1 Researchers say that far from being disccouraged, they’re heartened by the early results.
"Certainly, the national effort to implement directly observed therapy has had a marvelously beneficial effect on TB control," says Philip Brickner, MD, chairman of the department of community medicine at St. Vincent’s Hospital in New York City and lead researcher in the study.
"But when I talk to my colleagues who are working with the statistical part of the study," he says, "they say not to worry [about the paucity of conversions]. If we’re out there with our net,’ sooner or later we’ll catch some converters."
Shelters in six cities across the country will serve as their own basis for comparison, with placebo UV lights operating in a double-blind setup for part of the time.
The aim of the study is to find out once and for all whether UV lighting is truly the inexpensive deterrent to disease transmission its boosters believe it to be. To answer that question, Brickner and colleagues are studying high-incidence areas. "We’re working in cities where TB rates are far higher than average," he says. "As a separate demographic group, their rates are consistently running 10, 20, even 30 times higher than those of the general population."
As soon as researchers receive necessary funding, sites will begin operating in shelters in Los Angeles, where, with the city’s high incidence of TB infection among the foreign-born, rates of conversion should be higher than they’ve been so far.
The sites already producing data are in Birmingham, AL, New Orleans, and New York City. Addition-al sites in Houston and in four smaller towns in south Texas should be coming on board soon, Brickner adds.
In the meantime, researchers have been refining the art of installing UV fixtures in the most difficult spots imaginable, he says. Besides their occupants’ higher-than-average TB rates, shelters were selected precisely because of their architectural quirks. If UV light could work under such trying conditions, researchers reasoned, it could work anywhere. "The shelters [where we’re working so far] represent an enormous diversity of spaces," he says. "And even so, they’ve all been functionally fitted out. I’m no engineer, but I’ve been able to learn what goes into the decision about where to place fixtures."
Project engineers have come up with plenty of creative solutions, he adds: For example, when ceilings are extremely low, they hang a box containing a UV light and a fan on the wall. Nor has safety presented a problem: None of the fixtures has resulted in painful eye irritations or skin burns associated with improper UV light exposure.
Brickner emphasizes that he’s neutral on the subject of whether UV light ultimately will prove effective against TB. "But if it does," he adds, in comparison to administrative or ventilation solutions, "it will be the cheapest way by far we’ll have of preventing disease."
1. Brickner PW, Vincent RL, Nardell EA, et al. Ultraviolet upper room air disinfection for tuberculosis control: An epidemiological trial. J Healthcare Safety, Compliance, Infect Control 2000; 4.