Abstract #445

# 445
Ferret transmission model for tuberculosis.
Tuhina Gupta1, Shelly Helms1, Kaori Sakamoto1, Steve Harvey1, Ted Ross1, Christopher Whalen1, Russell Karls1, Frederick Quinn*1, 1University of Georgia, Athens, GA.

Tuberculosis (TB) is a persistent infectious disease that threatens the health of people and numerous mammalian animal species worldwide. Estimates are that 9 million new human TB cases occur annually while animal illness rates are higher but the actual numbers are unknown. Epidemiology studies indicate that transmission among close contacts is the driving force behind TB epidemics. Until successfully treated or until infected animals are removed, cases will continue to transmit bacilli to contacts. Since antibiotic treatment for most infected animals is not practical, and a vaccine that generates sterilizing immunity has not been developed, a vaccine that controls disease transmission may be the current best path forward. Unlike rodents, infected larger animals including cattle and non-human primates (NHPs) can effectively transmit the bacilli to naïve hosts via the aerosol route; however, routine work with statistically significant numbers of cattle and NHPs is cost-prohibitive. Thus, an appropriate small animal TB transmission model for assessing vaccines is needed. Ferrets are widely employed to study the transmissibility of influenza viruses and other respiratory agents, but thus far, no studies examining these parameters for Mycobacterium bovis (Mb) and M. tuberculosis (Mtb) have been reported. We know that mice and guinea pigs intratracheally or intravenously infected with virulent Mtb and Mb bacilli develop acute disease and ultimately succumb. This is not the disease process observed in humans and animals in natural settings. In high-exposure locations, TB contacts have been found to develop acute disease but remain TST-negative and free of the pathogen, remain TST-negative but carry viable bacilli in their airways, or become TST-positive but remain culture negative. In other words, natural transmission results in variable disease responses. Our team has generated exciting preliminary data demonstrating that ferrets can become infected when given intratracheal Mtb bacilli, but most importantly, transmission occurs when infected transmitter animals interact with naïve sentinels co-housed over the course of at least 2 mo. Additionally, the TB disease states described above also are observed in naturally-infected ferrets.

Key Words: tuberculosis, tranmission model

Speaker Bio
Frederick D. Quinn is a professor of infectious diseases and department head at the University of Georgia. Quinn oversaw several laboratory groups at the Centers for Disease Control and Prevention in Atlanta investigating bacterial disease outbreaks including Brazilian Purpuric Fever, Cat Scratch Disease, meningococcal meningitis, Buruli ulcer, and ultimately tuberculosis (TB). Before accepting the position at UGA, Quinn completed a Fullbright Fellowship studying TB pathogenesis at the University of Bristol in Great Britain. In early 2002, he became professor and head of infectious diseases in the College of Veterinary Medicine at the University of Georgia. The department research and teaching emphases include host-microbe interactions and the development of appropriate animal models, vaccine candidates, diagnostic tests and novel therapies for many parasitic, viral and bacterial human and veterinary emerging and zoonotic infectious diseases. Quinn’s research focuses on understanding the pathogenesis of Mycobacterium tuberculosis and M. bovis with the ultimate goal of developing improved vaccines and diagnostic tests for TB. Current collaborative activities include TB vaccine animal efficacy testing, animal model development for TB transmission, TB social networking and zoonotic transmission studies in Africa.