Animal & Veterinary
NATIONAL ANTIMICROBIAL RESISTANCE MONITORING SYSTEM (NARMS) UPDATE
by Marissa A. Miller, D.V.M., M.P.H.
FDA Veterinarian Newsletter September/October 1998 Volume XIII, No V
The National Antimicrobial Resistance Monitoring System (NARMS) was established in January, 1996 as a collaborative effort among the FDA, U.S. Department of Agriculture (USDA), and the Centers for Disease Control and Prevention (CDC). The system was initiated in response to public health issues associated with the approval of fluoroquinolone products for use in poultry. The NARMS program monitors changes in susceptibilities to 17 antimicrobial drugs of zoonotic enteric pathogens from human and animal clinical specimens, from healthy farm animals, and from carcasses of food-producing animals at slaughter. The objectives of the system include: to provide descriptive data on the extent and temporal trends of antimicrobial susceptibility in Salmonella and other enteric organisms, to facilitate the identification of resistance in humans and animals as it arises, and to provide timely information to veterinarians and physicians. The ultimate goal of these activities is to prolong the lifespan of approved drugs by promoting prudent and judicious use of antimicrobics and taking appropriate public health action. Another important outcome of these activities is the identification of research questions and areas for more detailed investigation. The system is set up as two nearly identical parts: a veterinary arm and a human arm. Veterinary testing is conducted at the Agricultural Research Service’s (ARS) Russell Research Center in Athens, Georgia. Human-origin isolates are sent in by 16 State Departments of Health for testing conducted at the National Center for Infectious Disease, CDC, in Atlanta, Georgia.
Important augmentations of the NARMS program were made possible by funding from the President’s Food Safety Initiative during fiscal year 1998. These augmentations include expanding the scope of the monitoring system and conducting follow-on research and investigations. The most important expansion of the monitoring system has been to include Campylobacter and E. coli isolate testing and reporting on the veterinary side. Human Campylobacter isolates had been included in the monitoring system beginning in 1997. In addition, new sites and sources of isolates have been added. In fiscal year 1998 the veterinary system is incorporating large numbers of Hazard Analysis Critical Control Point (HACCP) isolates into its sample to reflect the risk from resistant pathogens in the food supply. In an attempt to mirror the reporting of clinical isolates through the human arm, the veterinary arm has incorporated isolate collection from 3 sentinel sites. The three sentinel sites added during 1998 were veterinary diagnostic laboratories in New York, Washington, and California. Additional sentinel sites are to be added in fiscal year 1999.
With the additional funding provided by the Food Safety Initiative Surveillance budget epidemiologic research has been initiated. This research is to characterize and reduce the incidence of foodborne disease associated with emerging and drug-resistant pathogens and includes a field study, several farm-based efforts, and molecular genetic research. FDA in collaboration with ARS and the Vermont Department of Health are currently in the field studying risk factors associated with an outbreak of Salmonella typhimurium DT104 on a Vermont dairy farm. Information from this field study will be used to educate farmers to prevent future outbreaks and spread of this multi-resistant organism among animals and to man. Also in collaboration with ARS and with backing from the poultry industry, on-farm poultry studies have been initiated in 5 states to elaborate management, production, and drug use practices that influence the development of resistant zoonotic pathogens. Collaborative molecular genetic studies have been funded with the National Center for Toxicological Research (NCTR)-a sister FDA Center, to identify regions of fluoroquinolone resistance in zoonotic enteric organisms. This information will be used to develop genetic molecular detection capabilities. Later these techniques will be applied to zoonotic enterics and environmental bacteria to provide improved monitoring for resistance emergence and transfer. This work will significantly improve CVM’s ability to monitor for the safety of competitive exclusion products and new antimicrobial approvals.
Plans for the future include further augmentation of the existing system and new activities. Exciting new activities that will be pursued in fiscal year 1999 pending budget increases include the development of an international veterinary resistance database in order to facilitate international response to resistance emergence and spread throughout the world. Also planned are veterinary and producer drug prescribing surveys to assess the impact of antimicrobial use patterns on resistance emergence and prevalence in collaboration. This work is planned with the Center for Epidemiology and Animal Health, USDA through surveys conducted as part of the National Animal Health Monitoring System.