Disease Surveillance during the Reintroduction of the Iberian Lynx (Lynx pardinus) in Southwestern Spain

Abstract

The restoration of Iberian lynx (Lynx pardinus) populations in Extremadura (Southwestern Spain) have been carried out since 2014. One of the measures to ensure the success of this program is to examine the effects that diseases may have on reintroduction. Since diseases may be greatly located at certain sites because of the specific ecological requirements of the pathogens and/or vectors, reintroduced individuals may present a risk of infection once released. To determine which pathogens the reintroduced individuals may encounter, we performed a molecular and sero-epidemiological survey in reintroduced and wild-born lynxes. From 2015 to 2019, 69 Iberian lynxes (40 reintroduced and 29 wild-born) were sampled and screened against 10 viral, bacterial and piroplasmid agents. In parallel, 195 sympatric carnivores from the families Canidae, Felidae, Viverridae, Herpestidae and Mustelidae were tested against current or past infections to six common canine/feline viruses. In the Iberian lynx, low contact rates of active infection were obtained for the feline leukemia provirus (FeLV: 1.5%; 1/67), feline parvovirus (FPV: 1.5%; 1/67) and Cytauxzoon sp. (6.7%; 1/15). We also confirmed the emergence of Aujeszky’s disease (suid herpesvirus-1) in this population (SuHV-1: 11.8%; 2/17). Evidence of previous exposure was detected for canine distemper virus (CDV: 5.8%; 3/52), feline coronavirus (1.9%; 1/52), FPV (7.7%; 1/13) and feline calicivirus (FCV: 5.3%; 1/19). From 25 recovered lynx carcasses, we could confirm infectious etiology involvement in the death of four individuals (SuHV-1 in two individuals, coinfection of Cytauxzoon spp. and Aeromonas veronii in one lynx and a Streptococcus canis myositis in another lynx). We confirmed the circulation of CDV, FPV, FeLV, FCV and the feline immunodeficiency virus within the sympatric carnivore community. Due to the low contact rate of infectious agents in such a small, endangered population, we recommend continuing a disease surveillance program to determine the prognostic factors of survival, understand the role that disease may play during the reintroduction and anticipate disease outbreaks that may pose a risk for the entire reintroduced population.

Pseudorabies Virus Associations in Wild Animals: Review of Potential Reservoirs for Cross-Host Transmission

“…These results suggest that the Iberian lynx is susceptible to PRV and may be exposed to the virus via the consumption of wild boar meat [ 82 ]. Molecular and seroepidemiological analysis further confirmed the emergence of PRV in the Iberian lynx population (11.8%, 2/17) [ 13 ].…”

“…The Iberian lynx ( Lynx pardinus ), one of the most endangered feline species in the world [ 53 ], preys on small ungulates, birds, reptiles, and occasionally wild boar [ 82 ] and is positive for feline leukemia provirus (FeLV), feline parvovirus (FPV), and Cytauxzoon sp. by using PCR assay [ 13 ]. A previously captured lynx was found to be PRV-positive based on blood, oropharyngeal swab, and rectal swab samples, with PRV antigens also detected in the tonsils, brain, and gastric glandular epithelial cells [ 53 ].…”

“…PRV-related morbidity and mortality depend on various factors, such as animal health, viral strain, and infectious dose [ 5 ]. To date, PRV has been detected in various wild animals, including boars [ 6 ], rats [ 7 ], bears [ 8 , 9 ], raccoons [ 10 , 11 ], panthers [ 12 ], Iberian lynx [ 13 ], wolves [ 14 ], bats [ 15 ], and cats [ 16 ], as well as in domestic and farm animals, such as dogs [ 17 , 18 , 19 ], cattle [ 20 , 21 , 22 ], cats [ 23 ], sheep [ 24 , 25 ], foxes [ 26 , 27 , 28 ], and minks [ 29 , 30 , 31 , 32 ]. Furthermore, PRV infection is also a potential threat to humans [ 33 , 34 , 35 , 36 ].…”

Patterns of Exposure and Infection with Microparasites in Iberian Wild Carnivores: A Review and Meta-Analysis

“…After the outbreak, FeLV vaccination of all non-viremic captured free-living and captive lynx was implemented [ 46 ]. Since regulated necropsies of dead lynx were implemented, other pathogens have been shown to contribute to mortality of this species, including CDV [ 47 ], ADV [ 48 , 49 ], M. bovis [ 43 ], and Streptococcus canis [ 50 ]. Such findings have spurred many other studies on carnivore diseases in Portugal and southern Spain to provide a more comprehensive characterization of the pathogens circulating in areas of lynx reintroduction [ 49 , 51 , 52 ].…”

Hepatitis E virus in the endangered Iberian lynx ( Lynx pardinus )

“…As a result, the Iberian lynx census has soared during the last decade, reaching more than 1,100 free‐ranging individuals in 2020 ( Ministerio para la Transición Ecológica y Reto Demográfico, 2021). The monitoring of pathogens that could affect the Iberian lynx in the two different epidemiological habitats in which it is found (in captivity and in the wild) is a key component of the conservation programs of this endangered species, and health surveillance programs are being conducted in both free‐living and captive populations (Nájera et al., 2021; Rivas et al., 2016). Nevertheless, information about the susceptibility of the Iberian lynx to pathogens that are not monitored but highly prevalent in their habitat, which may be important in terms of conservation and animal and public health, is still very limited.…”