the mission of the organization, its goals, requirements and priorities. The true art of shelter medicine involves balancing risks to best serve overall objectives, especially those that are potentially in conflict with one another. Balancing isolation and confinement for infectious disease control with allowing exercise, social interaction and contact with adopters is just one example.
The recommendations in this text aim to highlight some of the ways in which risk and reward balance in a shelter vary in comparison to other contexts. Methods are suggested to mitigate risks while maximizing the shelter's ability to meet their goals. Paradoxically, veterinarians can sometimes best contribute to overall shelter success by recommending practices that are seemingly less cautious rather than more when it comes to infectious disease control. For instance, routine quarantine of healthy‐appearing incoming animals is commonly recommended in herd‐health contexts to screen for animals that may be incubating disease. However, the increased length of stay (LOS) this practice entails, along with the increased population density as well as the cost and staff burden that results, often undermine other goals of the shelter such as judicious use of limited resources and rapid movement of healthy animals into adoptive homes. Alternative strategies to limit disease introduction, without the need for quarantine, include accurate history taking when possible, the performance of careful intake exams and vaccination, daily rounds and monitoring, optimized sanitation procedures and appropriate and prompt use of diagnostic testing. These topics are covered in more detail in Chapter 2 on Wellness and elsewhere in this text.
1.1.3 What's New in the Second Edition?
As with any subject, the understanding of infectious disease management has evolved in the decade since the publication of the first edition. Ongoing research has refined the profession's knowledge of complex and emerging diseases such as feline leukemia and canine influenza, leading to updated recommendations for diagnostic testing and management in shelter animals. Practical field experience has also honed understanding of the best ways to manage long‐standing problems. For instance, at the time of publication of the first text, the use of antibody titers and RT‐PCR (reverse transcription‐ polymerase chain reaction) testing for the management of canine distemper outbreaks was relatively new. These methods have now been proven effective in managing many shelter outbreaks, leading to expanded opportunities for non‐lethal responses to this potentially devastating illness.
Alongside these advances in understanding disease management, new products have also led to expanded opportunities to preserve shelter animal health. For instance, accelerated hydrogen peroxide (Rescue™) has become a widely used disinfectant in shelters over the last 10 years. This product's reliability against viruses, safety, rapid action, multiple uses and relatively good penetration into organic matter have allowed more efficient sanitation strategies as well as more flexible use of housing materials. Another example is the development of “portals” to conjoin two cages into one more spacious double‐compartment unit, allowing segregation of eating and resting areas from those used for elimination. The reduced handling and disease transmission associated with double‐compartment housing, along with reduced stress, have led to reported reductions in feline upper respiratory infections (URI) of 70% or more at some shelters (CFHS 2018; Karsten et al. 2017).
The second example above highlights the impact of a growing body of shelter‐specific research that extends well beyond the traditional arsenal of infectious disease management tools. The development of the portal was based on the finding that the risk for feline URI was dramatically lessened by the provision of >8 ft2 floor space in cage housing during the first week of care (Wagner et al. 2018). Another study documented improved immunity and decreased feline URI risk associated with consistent, gentle human interaction with cats (Gourkow and Phillips 2015). The importance of such non‐traditional approaches to disease management is reflected in Chapter 2 on Wellness and elsewhere throughout this text.
1.2 The Growth of Shelter Medicine
While scientific advances have been significant, one of the most dramatic developments regarding disease control in shelters has been the rapid evolution of the field of shelter medicine itself. The original edition of this book was published within a decade of such milestones as the first formal course in shelter medicine (taught at Cornell University in 1999), the establishment of the first Shelter Medicine residency training program at UC Davis in 2001, and the founding of the Association of Shelter Veterinarians (ASV) in that same year. Many veterinary colleges have since incorporated shelter medicine classes and shelter externship opportunities into their core and elective curricula.
In the decade since then, the rapid expansion of shelter medicine has been a striking development within veterinary medicine as well as within the field of animal sheltering. From a disease control perspective, a major milestone was reached with the publication of the ASV Guidelines for Standards of Care in Animal Shelters in 2010. This document addressed everything from shelter management, policy and record‐keeping; through population management, facility design and sanitation; to the maintenance of physical and behavioral health of animals. The guidelines provide a powerful foundation for any program to maintain shelter animal health because all these elements are interrelated.
In addition to the ASV shelter guidelines, there has been an explosion of resources regarding virtually every aspect of shelter animal care and management. Along with a second edition of the seminal textbook “Shelter Medicine for Veterinarians and Staff,” veterinary guidelines and/or textbooks now exist addressing data collection and interpretation in shelters; animal behavior for shelter veterinarians and staff, forensic medicine; high quality, high volume spay/neuter, and more. Websites maintained by shelter medicine programs at various veterinary colleges (e.g. UC Davis, Cornell, the University of Florida, University of Wisconsin) and organizations such as the American Society for the Prevention of Cruelty to Animals (ASPCA) and Maddies' Fund are just a few of the resources that provide useful and practical information for shelter medicine professionals.
The development of shelter medicine as a veterinary specialty has accompanied this proliferation of resources and research. The American Board of Veterinary Specialties conferred provisional recognition of shelter medicine as a specialty within the American Board of Veterinary Practitioners (ABVP) in 2014, and the first diplomates were certified the following year. As more veterinarians seek and attain board certification in shelter medicine, the pool of research and expert consultants to support successful disease‐control programs in shelters will continue to grow.
1.2.1 Continued Advances in Animal Shelter Management
Advances in shelter medicine over the last decade have paralleled and supported the rapid evolution of animal‐shelter management and community policy concerning abused, homeless and free‐roaming dogs and cats. These changes, in turn, have resulted in substantially improved outcomes for shelter animals in many regions. A national database, Shelter Animals Count, (www.shelteranimalscount.org) has been developed to document these trends within the United States. Improvements to cat outcomes have been particularly striking. In 2018, the Million Cat Challenge (www.millioncatchallenge.org) announced that over 1,300 member shelters increased life‐saving success compared to each shelter's baseline by over 1.1 million cats in the four years from 2014 to 2018.
With improved outcomes, a positive cycle has been created that further supports successful programs to control disease. Though the belief that euthanasia should be reserved for dangerous or suffering animals is a widely shared value, historically, the number of live outcomes has failed to keep pace with the rate at which healthy animals were admitted to many shelters. This created a painful dilemma: either euthanize healthy animals to create space or permit crowding and allow the resultant disease to take its toll. Non‐lethal methods to balance shelter intakes with live outcomes are therefore a potent tool to maintain shelter animal health and welfare.
The practice