A not-so-surprising new study finds that people don't like rats. But what may be truly surprising is that rats — more than crime or other signs of urban decay — may make people depressed.
People living in Baltimore's low-income neighborhoods who see rats as a big problem are significantly more likely to have depressive symptoms such as sadness and anxiety, the research finds.
"Nobody likes living around rats," said Danielle German, who led the study done by the Johns Hopkins Bloomberg School of Public Health.
Rats often go along with other problems, such as vacant housing, drug sales on the street and the risk of being robbed and beaten up. But the study found that the relationship between rats and depression held firm even when accounting for other troubling neighborhood conditions.
Getting rid of rats, they concluded, may do a lot to help people dragged down by crime and poverty.
"This study provides very strong evidence that rats are an underappreciated stressor that affects how people feel about their lives in low-income neighborhoods," German said.
"The good news is it's modifiable. If we can do something to reduce the number of rats in these neighborhoods, we can improve people's well-being."
The team surveyed 448 low-income urban residents in Baltimore. "First, we explored how frequently low-income residents saw rats nearby and investigated the frequency threshold at which residents consider their block to have a notable rat problem," they wrote in the Journal of Community Psychology.
"More than 60 percent reported seeing rats at least weekly in the neighborhood and about 50 percent reported daily rat exposure within the neighborhood; approximately 50 percent reported rat exposure on their block at least weekly and 35 percent saw rats on the block almost daily; 13 percent reported rats in their home; and about 5 percent reported daily or almost daily rat sightings in the home."
Those who said rats are a big problem were 72 percent more likely to also report symptoms of depression. They also frequently felt helpless to do anything about the rats.
"Despite public health attention to rats as a source of infectious disease and popular attention to urban rats, there have been relatively few efforts to understand community residents' experiences of rats," the team wrote.
"Notably, there has been little attention to the experience of rats as a potential stressor among those who live in high rat prevalence area In Baltimore, community groups consistently report rats and trash among their top concerns and the rat population has not decreased over time despite a variety of eradication efforts."
German said the findings are similar to those of a popular theory that has led to "broken windows" policing, in which the idea is to keep on top of small, everyday crimes and nuisances to prevent larger ones.
"Yes, eradicating rats from Baltimore City is a hard goal, but making it so no neighborhood has to see rats every day is a goal we can strive for," German said.