YSPH Hosts Animal Diseases Conference

Infectious–disease experts, zoologists and biostatisticians from Cambridge to Kazakhstan convened at the Yale School of Public Health April 3 and 4 for its first conference on zoonoses, infectious diseases with the potential to spread from animals to humans. Rabies, Lyme disease, Ebola virus and avian flu were just a few of the illnesses discussed over the two days, through the lenses of both forecast modeling and surveillance and intervention.

“We’re very committed to an inter–disciplinary approach,” Dean Paul Cleary told dozens of scientists and students gathered in Winslow Auditorium. “We need experts across the spectrum of science to build our work against the spread of infectious diseases.”

Durland Fish, professor in the division of Epidemiology of Microbial Diseases, organized the conference to foster a cross–disciplinary approach to tracking and controlling zoonoses on a global scale. Fish also serves as director of Yale’s Institute for Biospheric Studies Center for EcoEpidemiology, which sponsors forums on topics that integrate ecology with epidemiology to address issues pertaining to environmental and human health. “The overall objective was to bridge ecology with epidemiology, and we’ve put some planks in that bridge over these two days,” said Fish.

Maria Diuk–Wasser, assistant professor in the division of Epidemiology of Microbial Diseases, presented research that pointed to climate as a reliable predictor of the risks of contracting Lyme disease, the U.S.’s most frequently–reported vector–borne disease in humans. (Vector–borne zoonoses are transmitted through invertebrates such as insects.) Diuk–Wasser’s research identified two main areas of Lyme–causing ticks, known as Ixodes scapularis nymphs: the Northeast and Upper Midwest. Based on tick samples and weather–station data in 304 locations, a climate–based prediction of the nymphs’ population density emerged to help estimate the risk of humans acquiring different strains of the disease in different severities. “Our model can be used by the public, physicians and public–health agencies to better target Lyme disease prevention and control efforts,” said Diuk–Wasser.

Alumna Annie Gatewood Ph.D. ’08, now a fellow at Children’s Hospital Boston at Harvard Medical School, also discussed climate modeling to predict the distribution of different genotypes of the bacteria that causes Lyme diseases in humans. Like Diuk–Wasser, with whom she collaborated, Gatewood underscored the importance of weather in gauging tick population and behavior, and subsequent risk of human infection. “Given all the discussion of climate change, it’s a relevant topic,” said Gatewood.

Delegates from the centers of infectious diseases in Kazakhstan and Mongolia discussed their country’s struggles with tracking outbreaks of plague and tick–borne zoonoses. Closer to home, Meg Flanagan, a researcher at the Defense Threat Reduction Agency in the Department of Defense, called for a multi–disciplinary strategy of “predictive virus surveillance” in countering the threat of viruses—which are classified as weapons of mass destruction (WMDs). “Emerging viruses may inflict harm upon humans, crops, livestock, economies and our stability,” she said. To anticipate and control potential damage, she said, expert guidance is crucial for “looking in the right places, the right populations and the right viruses”—including zoonotic viruses proliferating in the wild.

Affirming the value of alliances, Peter Rabinowitz, director of clinical services for the Yale School of Medicine’s Occupational and Environmental Medicine program, invoked the urgent need to combine federal–agency databanks tracking illnesses in humans and animals, in order to forecast outbreaks of diseases such as avian flu. “At issue is the limited sharing of data among health agencies, and the limited use of animal data to predict human risk,” he said.

His talk, like many others, highlighted the need for collaboration among various disciplines to protect populations from animal–borne diseases. “The potential for an outbreak in the U.S. is low—but any outbreak should be regarded and addressed as a public health crisis,” said Heinz Feldmann of the National Institutes of Health, referring to ebola but echoing the exhortations of other speakers.