Raccoons (Procyon lotor) and Striped Skunks (Mephitis mephitis) as Potential Reservoirs of Leptospira spp. in California

Abstract

Leptospirosis is a globally important, fatal disease of humans, and over 160 species of animals are associated with more than 250 bacterial serovars in 64 species, but its ecology varies regionally and has changed over time with expansion of human development on previously agricultural and wild land. Sporadic human cases and clusters of canine leptospirosis, primarily attributable to Leptospira interrogans serogroup Pomona, have been detected in northern California. Small mesocarnivores such as raccoons and skunks frequent peridomestic space across much of the western United States and could serve as reservoirs for human and canine leptospirosis. We aimed to summarize the prevalence of infection with pathogenic leptospires in skunk and raccoon renal and urinary samples across broad geographic zones in California, and to determine whether prevalence changed during wet and dry seasons, and as functions of host species and demographic characters. Overall, 25.6% (22/86 tested) of raccoons and 28.5% (39/137 tested) of skunks were PCR-positive for Leptospira spp. in either renal tissue or urine, with leptospiral DNA in 22.0% of kidney samples and 18.8% of urine samples from raccoons and 27.8% and 14.5% of kidney and urine samples from skunks, respectively. Raccoons from the Central California and skunks from the San Francisco Bay Area had the highest overall PCR-prevalence (35.7% and 44.4%), respectively, and adults were more likely to be PCR-positive for Leptospira spp. than juveniles. There was moderate agreement between urine and renal tissue Leptospira spp. PCR with sensitivity for both host species in renal tissue of 0.86-0.97 and 0.42-0.64 in urine. Cases of human leptospirosis are thought to be underrecognized in the continental United States and possibly increasing in some states, including California. Our data document regionally high rates of infection in common mesocarnivores, which can pose a threat to humans and dogs, revealing an important periurban epidemiological cycle.

Bacterial and Viral Pathogens with One Health Relevance in Invasive Raccoons (Procyon lotor, Linné 1758) in Southwest Germany

“…It is probable, despite the high sensitivity and specificity of the established PCR methods, that the individual pathogens’ prevalences are underrepresented. Factors such as autolysis, tissue sample selection and sampling timing, which depend on pathogenesis and incubation time, may have influenced the detection rate [ 31 , 38 , 40 , 47 , 48 , 49 , 50 ].…”

“…From Japan but primarily from North America, there are many records of p L , mainly L. interrogans , with prevalences of up to 54.8% with a wide range of serogroups having been detected [ 16 , 31 , 32 , 61 ]. Raccoons are maintenance hosts which predestines them as sentinels for monitoring epidemiological changes in p L and for designating nationwide and regional high- and low-risk regions [ 31 , 32 , 61 , 62 ].…”

“…Accordingly, the raccoon may possibly impact the epidemiology of these pathogens in BW [ 7 , 13 ]. Furthermore, raccoons may help pathogens to persist in the environment for a more extended period, giving rise to new and occasionally more virulent variants of pathogens and contributing to epidemic outbreaks with sometimes high mortality events (CDV, CPPV-1) [ 17 , 20 , 22 , 23 , 31 , 32 , 44 , 61 ].…”

“…As a part of that survey, here we have focused on four viruses: the carnivore protoparvovirus-1 (CPPV-1) [ 17 , 18 , 19 , 20 , 21 ], canine distemper virus (CDV) [ 22 , 23 , 24 ], influenza A (IAV) [ 25 , 26 , 27 ] and West Nile virus (WNV) [ 28 , 29 , 30 ]; as well as two bacteria, the pathogenic Leptospira spp. (p L ) [ 21 , 31 , 32 ] and Anaplasma phagocytophilum ( Ap ) [ 16 , 33 , 34 ]. Using specific qPCR methods, we screened tissue and blood samples of randomly collected free-ranging raccoons in BW for the selected pathogens.…”

A review of investigated risk factors for developing equine recurrent uveitis

“…Some environmental factors, primarily infection by a spirochete bacterium from the genus Leptospira , have been implicated in the onset, progression, and severity of ERU 29–31 . In fact, case reports indicate that uveitis is also a sequela to leptospirosis in humans, dogs, and other mammals 32–39 . In addition to Leptospira , several other less common infectious agents, such as Rhodococcus equi (bacillus), Borrelia burgdorferi (spirochete), and some nematode parasites and viruses, have been associated with uveitis 40–46 .…”