COVID-19 associated reduction in elective spay-neuter surgeries for dogs and cats

Introduction

Overpopulation of cats and dogs is a global concern. Efforts to manage their population and to reduce the number of animals taken in and euthanized by animal shelters have largely focused on surgical sterilization to reduce unintended reproduction (1). In the US, the first clinics focusing on high-volume spay-neuter emerged in the 1970s (2). By the 1990s, pediatric sterilization became widely accepted, shelters adopted “neuter-before-adoption” policies, and training programs were developed to teach efficient surgical techniques in veterinary schools (3–5). The rise in subsidized spay-neuter access helped drive the euthanasia of shelter pets from an estimated 13.5 million in 1973 (6) to 1.5 million in 2019 (7).

The Association of Shelter Veterinarians defined high-quality, high-volume spay-neuter (HQHVSN) as “efficient surgical initiatives that meet or exceed veterinary medical standards of care in providing accessible, targeted sterilization of large numbers of cats and dogs to reduce their overpopulation and subsequent euthanasia” (8). Mentorship programs and grants were developed to spawn hundreds of clinics specializing in HQHVSN across the US (9). As a high percentage of owned pets were sterilized, attention turned to unowned free-roaming community cats as the primary source of kitten births, inciting trap-neuter-return (TNR) programs to manage their population (10, 11).

In January 2020, the novel SARS-CoV-2 virus reached the US and quickly spread from state to state. The federal government declared a public health emergency in February followed by a national emergency the next month. This triggered states to institute lockdowns beginning in March 2020 that closed schools, businesses, and non-essential public services intended to reduce viral transmission and to preserve medical supplies and personal protective equipment (PPE) for use by healthcare providers. Like their human healthcare counterparts (12, 13), veterinary associations developed guidelines for triaging veterinary care during the pandemic lockdown. While there was no standardized list of essential procedures in veterinary medicine, they were generally grouped into procedures needed to relieve animal pain and suffering, to prevent imminent death or deterioration, and to protect public health (14–16).

While veterinary providers continued to focus on life-threatening emergencies, such as pyometra and dystocia, they largely suspended elective procedures such as preventive care, treatment of minor or chronic conditions, and routine spay-neuter surgeries. Routine spay-neuter surgeries traditionally performed daily at animal shelters and HQHVSN clinics were deemed non-essential. The increased use of telehealth as a substitute for seeing animal patients in person alleviated some veterinary needs during lockdown but could not address the growing gap in spay-neuter services (17–19).

The severe and prolonged pandemic-related decrease in spay-neuter services may have the potential to undermine progress made in controlling pet populations and euthanasia in shelters. The purpose of this study was to examine the impact of the COVID-19 pandemic on the number of spay-neuter procedures performed by HQHVSN clinics in the US.

Materials and methods

Data collection

Spay-neuter data for dogs and cats were collected by Clinic HQ (Clinic HQ Inc, Portland, OR), a cloud-based clinic management software program designed for practices focusing on spay-neuter and preventive healthcare services from January 1, 2019 to December 31, 2021. A total of 400 spay-neuter clinics in the United States used the software, which the company estimates included 13% of the approximately 3,000 spay-neuter practices in the US. Of these, 188 were excluded from the study because they did not use the software for the entire baseline year of 2019. Comprehensive patient datasets collected from the remaining 212 clinics from January 2019 to December 2021 were included in this study. This period spanned the 2019 pre-pandemic baseline year of normal operations, the spring 2020 pandemic lockdown during which non-essential services were curtailed, and the following months as restrictions lifted across the country. All clinics were identified by a unique identification number, and the information was collected and stored in an electronic format. No identifiable client, patient or clinic information was stored with the data available for the study.

The data were categorized for both dog and cat populations for the following variables: sex (male vs. female), age (pediatric <5 months, adult 5 months to 7 years, and geriatric > 7 years), and ownership status. Ownership status included privately owned pets vs. unowned pets (community cats, pets from municipal and private shelters, and rescue organizations). Four geographic regions were used for analysis, based on the US census bureau regions (20): Northeast (Connecticut, Maine, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, Rhode Island, and Vermont), Midwest (Indiana, Illinois, Michigan, Ohio, Wisconsin, Iowa, Kansas, Minnesota, Missouri, Nebraska, South Dakota, and North Dakota), South (Delaware, District of Colombia, Florida, Georgia, Maryland, North Carolina, South Carolina, Virginia, West Virginia, Alabama, Kentucky, Mississippi, Tennessee, Arkansas, Louisiana, Oklahoma, and Texas), and West (Arizona, Colorado, Idaho, New Mexico, Montana, Utah, Nevada, Wyoming, Alaska, California, Hawaii, Oregon, and Washington).

Descriptive statistics

Data from 212 clinics from January 1, 2019 to December 31, 2021 were included in the analysis. The number of total surgeries performed each year and the absolute and percentage change from 2019 were determined for month, species, sex, age, ownership status, and geographical region.

Results

From a total of 400 spay-neuter clinics that currently used the software, 212 had complete spay-neuter surgery data for the entire 3-year study period. These clinics collectively performed 1,217,240 spay-neuter surgeries in the baseline year of 2019 (Table 1). Surgeries decreased 13% to 1,059,388 in 2020, then rebounded to 1,184,274 in 2021, still 3% below the baseline year. By December 2021, 8 clinics (4%) had temporarily closures, 4 clinics (2%) were permanently closed, and 2 clinics (1%) stopped performing spay-neuter surgeries and converted to wellness services only. In total, 190,818 fewer surgeries were performed by the 212 studied clinics in the 24 months from January 2020 through December 2021 than would be expected had 2019 levels been maintained.

TABLE 1

Table 1. Number of cats and dogs spayed or neutered, absolute change, and percentage change by month from January 2019 through December 2021.

Total surgeries per month were compared for the entire study period (Figure 1 and Table 1). The clinics started 2020 with 5% more surgeries in January and 4% in February than during the same period in 2019. A sharp decline in surgeries began in March 2020 (−22%) and reached a nadir in April 2020 (−80%) compared to the baseline year of 2019. Surgeries began to increase in May 2020 (−39%), before plateauing in June 2020 (−3%) and remaining slightly below baseline in most months throughout the rest of the study period (−17% to +9%).

FIGURE 1

Figure 1. Number of cats and dogs spayed or neutered per month at 212 spay-neuter clinics in the US during baseline year 2019, and COVID-19 pandemic years 2020 and 2021.

Trends in the spay-neuter data for dogs and cats were reported as the total number of animals per year, absolute change from 2019, and percentage change from 2019 (Table 2) (Supplementary Tables I, II). In 2019, a majority of surgeries were performed in cats (66%) vs. dogs (34%), a pattern that remained consistent throughout the study period. Total surgeries decreased in both dogs (−19% in 2020; −14% in 2021) and cats (−10% in 2020; +3% in 2021). A majority of surgeries in 2019 were performed in females (53%) vs. males (47%), and this pattern persisted throughout the study period. Total surgeries decreased in both females (−14% in 2020; −4% in 2021) and males (−12% in 2020; −1% in 2021).

TABLE 2

Table 2. Number of cats and dogs spayed or neutered, by species, sex, age, ownership status, and US regions in 2020 and 2021 compared to the baseline year of 2019.

Adult-aged animals (5 months to 7 years) were the largest group in 2019 (69%), followed by pediatric animals (<5 months) (30%) and geriatric animals (more than 7 years) (1%). Total surgeries decreased in geriatrics (−18% in 2020; −16% 2021), adults (−14% in 2020; 0% in 2021), and pediatrics (−11% in 2020; −8% in 2021). A majority of surgeries were performed in owned animals (63%) vs. unowned animals (37%), a pattern that remained consistent throughout the study. Total surgeries decreased in both owned animals (−12% in 2020; −1% in 2021) and in unowned animals (−14% in 2020; −5% in 2021).

Clinics in the South region performed the highest proportion of total surgeries in 2019 (47%), followed by West (23%), Northeast (21%) and Midwest (9%). Total surgeries decreased in the Midwest (−17% in 2020; −8% in 2021), the Northeast (−15% in 2020; −7% in 2021) and West (−15% in 2020; +2% in 2021), and the South (−11% in 2020; −2% in 2021).

Discussion

The COVID-19 pandemic led to a sudden and large reduction in the number of spay-neuter surgeries performed by spay-neuter clinics in March and April 2020. Surgeries began to rebound in May 2020, coinciding with the development of safety measures such as masking, physical distancing, testing, and curbside veterinary reception. In total, 190,818 fewer surgeries were performed by the 212 studied clinics in the 24 months from January 2020 through December 2021 than would be expected had 2019 levels been maintained. If a similar pattern was experienced by all 3,000 estimated spay-neuter clinics in the US, it would suggest a deficit of more than 2.7 million spay-neuter surgeries have accumulated by the end of 2021. The decrease in elective spay-neuter procedures observed in this study echoed a similar decline in elective surgical procedures in human medicine during the 7 weeks after the initial lockdown, a return to near 2019 numbers in the following months, and a deficit in total number of surgeries performed by the end of the first year of the pandemic (21). Since pandemic conditions have not yet resolved as of August 2022, spay-neuter clinics have not yet returned to baseline productivity, and an ongoing workforce shortage of veterinarians and staff threatens the spay-neuter recovery, conditions are ripe for an increase in unwanted litters and a reversal of population control gains of the past decade (22). Veterinary and animal welfare organizations should prioritize recovery of spay-neuter capacity and focus on populations most at risk for unintended reproduction, poor welfare, or entering the animal shelter system.

Clinics performed nearly twice as many feline vs. canine surgeries in the baseline year, and reduced canine surgeries almost twice as much as feline surgeries during the pandemic. While it is unknown why this cohort of clinics experienced this pattern, it could be related to the urgency associated with cats being euthanized at twice the rate of dogs in shelters, the proliferation of TNR programs for community cats, and the ease of performing cat surgery while simultaneously maintaining physical distancing (17, 23). Cat reproduction is highly seasonal, peaking in spring and summer. The delayed return of full capacity spay-neuter clinics has now spanned three “kitten seasons,” causing concern about population growth of free-roaming community cats (24).

Geriatric animals constituted the smallest age bracket in the baseline year and had the greatest reduction in surgery during the pandemic. Geriatric animals often require greater preparation for surgery, for example pre-surgical laboratory testing, and more intensive monitoring. This, combined with the fact that geriatric animals are at lower risk for unwanted reproduction, may explain the decrease in surgery for older animals (25, 26). The decrease in surgery was less marked for younger animals, with adults remaining the largest age group to have surgery throughout the study period. Adult animals are at immediate risk for reproduction, whereas juveniles would reach reproductive age after just a few months. Clinics performed a similar reduction in spays compared to neuters during the pandemic, even though female sterilization is most important for preventing unintended reproduction. The prolonged delay in return to normal spay-neuter operations is especially concerning for female cats as they can become pregnant as early of 5 months of age, which underpins the recommendation that cats be sterilized before 5 months of age (27).

Unowned pets (community cats and pets from shelters and rescue organizations) experienced a similar decrease in spay-neuter surgeries compared to privately owned pets. This may be related to the completion of pre-existing surgery appointments for owned pets as well as reduced numbers of animals held in shelters. Many animal shelters suspended “neuter-before-adoption” policies in order to quickly move shelter pets into permanent or foster homes as they sought to reduce shelter pet populations during the transition to essential services only (28, 29). Alternatives included releasing pets with contracts or vouchers to have them sterilized when spay-neuter capacity resumed or placement with “foster-to-adopt” agreements in which ownership was not transferred until documentation of sterilization was provided (30). In addition, the National Animal Care and Control Association (NACA) advised suspension of trapping and intaking healthy community cats or other animals not in immediate danger during the pandemic (29, 31).

The decrease in surgery coincided with the high number of COVID-19 cases early in the pandemic. In April 2020, there were nearly 400,000 reported cases of SARS-CoV-2 infection in the US. Of these, 54% were from states in the Northeast, leading to stricter business lockdowns in this region (32). The Midwest, West, and Northeast regions of the US had the largest proportional decline in spay-neuter surgeries. Pet population numbers in the Northeast in particular are generally in balance with demand for pets (6, 33), shelters are not overcrowded, and the per capita demand for HQHVSN services is lower than in other regions where pet overpopulation persists. In contrast, pet overpopulation, shelter crowding, and euthanasia for population control is highest in the South, where spay-neuter activity remains a high priority. Clinics in the South collectively performed the most surgeries before and during the pandemic and experienced the smallest proportional decline in surgeries during the pandemic. COVID-19 restrictions and mandates were lifted at different times for each state, which affected when shelters and clinics could begin returning to normal operations. Northeast states such as Connecticut, lifted most business restrictions in May 2021, while Southern states were less restricted throughout the pandemic (34). The future impact of the spay-neuter gap across regions is likely to be complex as it is influenced not just by the number of surgeries, but also by factors such as mild climates that support greater survival of offspring, the pre-existing number of free-roaming animals, particularly community cats, and regional access to low-cost veterinary care in underserved communities.

Guidelines specifically aimed at safe practices in spay-neuter clinics became available soon after the initial pandemic lockdown (24, 35). However, as the pandemic became prolonged, providers experienced staffing shortages associated with an ongoing veterinary workforce shortage compounded by the impact of the pandemic depleting staffing numbers due to SARS-CoV-2 infections, quarantines, and the need to stay home with children and other dependents (36). These staffing shortages threaten to undermine the recovery of HQHVSN programs and other animal welfare initiatives. When spay-neuter capacity is limited, providers can prioritize patients based on both safety and urgency (35, 37). When COVID activity is high and physical distancing is important, selecting animals and procedures that reduce personnel contact reduces the risk of workplace transmission (14). For example, use of intramuscular anesthetic induction protocols and selection of smaller patients, such as puppies, cats, and small breed dogs, make it possible for a single staff member to prepare a patient for surgery. Surgery and recovery times are shorter in juveniles and small adults, enabling more surgeries to be completed when capacity is limited (38). In addition to treating reproductive emergencies, providers can prioritize animals most at risk for unintended reproduction, such as pregnant animals, mixed sex litters, females, and community cats, as well as animals at risk for behavior issues such as spraying by intact male cats.

Limitations of this study include the use of a single baseline year, whereas a longer time would have provided more information about temporal trends of spay-neuter surgeries prior to the pandemic. Focusing exclusively on clinics utilizing the Clinic HQ spay-neuter specialty software excluded evaluation of surgery trends in full-service practices and organizations utilizing other veterinary management software programs. However, this software is widely used in the HQHVSN industry. Given the size of the dataset and the broad geographical representation, the authors believe it is illustrative of spay-neuter trends across the US. Although significant differences as a function of species, age, ownership, and region were observed, the study design did not provide a means to determine the reason for the differences, whether they were intentional, or to what extent lockdowns, funding, and/or staffing played a role.

Conclusion

At the beginning of 2020, a cohort of 212 spay-neuter clinics that collectively performed more than 1 million surgeries per year were on track to increase surgeries by 5% over the previous year. The COVID-19 pandemic lockdown resulted in a drastic reduction of surgeries, from which the industry has not yet recovered. The high level of spay-neuter achieved over the past five decades is the single most important driver of reduced pet overpopulation and euthanasia in animal shelters. Veterinarians and animal welfare organizations should collaborate to prioritize recovery of spay-neuter capacity with a special focus on serving populations most at risk for unintended reproduction, poor welfare, or entering the animal shelter system.

Data availability statement

The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.

Author contributions

JL and GC conceptualized the research topic. GC, SG, and TP compiled the data sets. TD performed statistical analysis. SG, TP, and JL prepared the manuscript. All authors contributed to the article and approved the submitted version.

Funding

This work was supported by a summer research grant provided through the Boehringer Ingelheim Veterinary Scholars Program and the Department of Small Animal Clinical Sciences at the University of Florida College of Veterinary Medicine.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher's note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

Supplementary material

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fvets.2022.912893/full#supplementary-material

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