Survey ofStaphylococcus aureuscarriage by free‐living red deer (Cervus elaphus): Evidence of human and domestic animal lineages

Abstract

Staphylococcus aureus is a pathogen that can affect multiple host species. Evidence of transmission between humans and animals and among different animal species has been reported in recent years. In this study, we investigated 284 free-living red deer (Cervus elaphus) in the Central Italian Alps to assess the prevalence and molecular characteristics of S. aureus in nasal and intestinal samples in relation to host features and environmental factors. A prevalence of 90%, 26.2% and 10.7% of S. aureus was detected in nasal rectal swabs and faeces, respectively. Calves had a higher probability of being S. aureus intestinal carriers than adults, especially in females when considering faecal samples. Clonal complex (CC) 425 was the most prevalent lineage (61.5%). This is a lineage known to be widespread in both domestic and free-living animals. It was followed by CC2671 (15.4%) and CC350 (6.4%). A high rate of the phage-borne virulence factor lukM/lukF-P83 was detected in CC425 and CC350. Further lineages, which are known to occur in both humans and animals, were detected sporadically in red deer faeces only, that is, CC7, CC9, CC121 and CC707, harbouring the genes of the penicillinase operon and a gene for macrolide resistance (CC9 and CC121). Methicillin resistance genes mecA and mecC were not found. Our results suggest that free-living red deer may be reservoir for S. aureus in Alpine habitats. K E Y W O R D Scervidae, DNA microarray analysis, multi-host pathogen, red deer, Staphylococcus aureus, wildlife INTRODUCTIONStaphylococcus aureus is a generalist bacterial species that inhabits mucosae and skin in humans and animals (Haag et al., 2019;Tong et al., 2015), and whose primary ecological niche is found in the nares.

Characterisation of a Staphylococcus aureus Isolate Carrying Phage-Borne Enterotoxin E from a European Badger (Meles meles)

“…Phage-borne leukocidin genes lukF -P83/ lukM have been observed in some ST425-MSSA isolates from Italian Red deer [ 45 , 60 ] but neither in published sequences nor in the badger isolate.…”

“…This is a clonal complex that has previously been described as a widely disseminated, highly virulent rabbit strain [ 38 ], but there were no further genotyping data available so that especially the toxin gene carriage of these rabbit isolates cannot be compared to our badger isolate. This lineage has also been found in red deer, roe deer, wild boar, red fox and cinereous vulture [ 6 , 40 , 41 , 42 , 43 , 45 ]. In addition, mecC -MRSA from this lineage has been identified in cattle [ 39 ].…”

“…An earlier study on European wildlife identified four isolates among 29 examined animals [ 6 ]. Three were identified as CC425 (a lineage also known from various animals, see below and [ 6 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 ] and one was assigned to CC25 (previously found in humans, [ 46 , 47 , 48 ]). A recent study from Spain [ 49 ] did not identify S. aureus in the twelve badgers examined, and another one from Northern Ireland failed to detect MRSA in badgers [ 50 ].…”

Parasite-mediated manipulation?Toxoplasma gondiiinfection increases risk behaviour towards culling in red deer

“…Other infections were detected in our study population. For example, red deer are an asymptomatic reservoir of Shiga toxin-producing Escherichia coli and Staphylococcus aureus , which may have zoonotic potential [34,35], but none of them are related to the probability of being culled.…”