What Post-Katrina New Orleans Taught Us About Urban Rats

When natural disasters strike, the drastic environmental changes often bring public health concerns to the forefront of recovery efforts. Following the 2010 earthquake in Haiti, officials and international agencies rushed to curb the cholera outbreak caused by contaminated drinking water. And in the wake of Hurricane Katrina, officials in Louisiana cleared more than 38 million tons of debris in part to reduce the spread of bacterial diseases like leptospirosis, transmitted to humans via infected animals—namely, rats.

It’s not only the disasters themselves that bring humans and disease-carrying agents closer, says Michael Blum, a molecular ecologist at Tulane University. Human response to disasters also plays a key role. Since 2013, New Orleans has become a lab for scientists like Blum to study disaster ecology, or the environmental impacts of disaster and recovery. While researchers in this field commonly study mosquitoes—carriers of the deadliest vector-borne diseases—Blum focuses on rats.