Canines as Sentinels for Lyme Disease in San Diego County, California

Abstract

Abstract. Prevalence of Lyme borreliosis in canine sentinels has been shown to correlate with infection in humans. One thousand canine sera (917 dogs, 83 coyotes) obtained from animal control authorities and area veterinarians were screened by ELISA for antibodies to Borrelia burgdorferi. Results were validated by Western blot and indirect fluorescent antibody (IFA) tests at referee laboratories. Criterion for a positive Western blot was presence of 5 of 10 of the most common antigen IgG bands; for IFA, Ͼ1:128 or the equivalent when correcting for interlaboratory variability. Twenty-two of 1,000 canines were confirmed serologically positive (21 dogs and 1 coyote; seroprevalence 2.3% and 1.2%, respectively). Lifestyle, breed size, gender, and age were not statistically predictive of seropositive status. No regional clustering of seropositive animals was detected. The low prevalence of seropositivity in sentinel canines suggests the Lyme borreliosis hazard in San Diego County is minimal.Lyme disease (or LB, Lyme borreliosis) is a multisystem infection transmitted by ixodid (hard-bodied) ticks and caused by the spirochete Borrelia burgdorferi. The effects of Lyme disease are not limited to humans; disease has been described in cats, dogs, horses, goats, and cattle. 1,5,19 Dogs, because of their proximity to humans and apparent higher risk of infection, have been used as sentinel animals to determine B. burgdorferi endemicity. 2,8,9,15,17,23 San Diego County, California, is a large and ecologically diverse region comprising 4,500 mostly rural square miles and defines the southwestern margin of California and the United States. This study, utilizing serologic testing of dogs and coyotes, addressed whether B. burgdorferi is enzootic in this area. The data indicate very low or insignificant infection rates. Materials and methodsCanine sera were solicited from local veterinarians, trappers, animal shelters, and humane societies. Samples were collected over 1 yr (Mar 1992-Mar 1993. One thousand canine sera were obtained (917 dog, 83 coyote). Sera were initially screened by ELISA a and were considered ELISA positive if spectrophotometrically three standard deviations above mean optical density of samples from control animals. To improve specificity testing, ELISA-positive sera were to In immunoblotting, the criterion for a positive Western blot was established as the presence of 5 of 10 of the most common antigen IgG bands (18,21, 28, 30, 39, 41, 45, 58, 66, and 93 kD) (J. J. Marx, Marshfield Research Foundation, personal communication). In IFA confirmatory testing, titers 1: 128 were considered positive; 18 because one referee laboratory consistently tested one dilution lower, 1:64 was accepted as representing a positive determination from that facility. Because cases were identified by serodiagnosis, the main outcome or dependent variable was confirmed seropositivity. Nine independent variables were considered: species of canine (Canis familiaris vs. Canis latrans), age, gender, breed size, residence lifestyle (rural, u...

Establishment of brown anoles (Anolis sagrei) across a southern California county and potential interactions with a native lizard species

“…Any negative interactions from this A. sagrei invasion may have the potential to change mechanisms of the tick-Lyme disease interaction in southern California (Swei et al, 2011). There is some evidence to suggest mechanisms could be changing with Lyme disease detected in dog sera of urban San Diego dogs in the highest prevalence, compared to natural habitats, suggesting that changes in S. occidentalis populations could be relevant to disease prevalence change over time, even in the urban landscape (Olson et al, 2000).…”

White‐Tailed Deer (Odocoileus virginianus) as a Potential Sentinel for Human Lyme Disease in Indiana

“…Nevertheless, no study has reported on the association between Bb detected in I. scapularis collected from deer and human LD. Furthermore, dogs have been extensively studied as suitable sentinels for human LD (Lindenmayer et al., 1991; Daniels et al., 1993; Olson et al., 2000; Duncan et al., 2005; Hamer et al., 2009). A few of these studies, however, assessed the association between human and dog LD (Lindenmayer et al., 1991; Daniels et al., 1993; Guerra et al., 2001) using serum samples.…”

Serologic Survey of Select Infectious Diseases in Coyotes and Raccoons in Nebraska

“…Because of this, mammalian predators have been the focus of numerous disease investigations and have been recommended as sentinels for wildlife and zoonotic diseases (Thomas and Hughes, 1992;Mitchell et al, 1999;Olson et al, 2000). Coyotes (Canis latrans) and raccoons (Procyon lotor) are ideal candidates for surveillance studies because both species are common and widespread in North America (Bekoff, 1982;Kaufmann, 1982).…”