title: Patterns of Mycobacterium tuberculosis-complex excretion and characterization of super-shedders in naturally-infected wild boar and red deer.
abstract: Wild boar (Sus scrofa) and red deer (Cervus elaphus) are the main maintenance hosts for bovine tuberculosis (bTB) in continental Europe. Understanding Mycobacterium tuberculosis complex (MTC) excretion routes is crucial to define strategies to control bTB in free-ranging populations, nevertheless available information is scarce. Aiming at filling this gap, four different MTC excretion routes (oronasal, bronchial-alveolar, fecal and urinary) were investigated by molecular methods in naturally infected hunter-harvested wild boar and red deer. In addition MTC concentrations were estimated by the Most Probable Number method. MTC DNA was amplified in all types of excretion routes. MTC DNA was amplified in at least one excretion route from 83.0% (CI95 70.8-90.8) of wild ungulates with bTB-like lesions. Oronasal or bronchial-alveolar shedding were detected with higher frequency than fecal shedding (p < 0.001). The majority of shedders yielded MTC concentrations <10(3) CFU/g or mL. However, from those ungulates from which oronasal, bronchial-alveolar and fecal samples were available, 28.2% of wild boar (CI95 16.6-43.8) and 35.7% of red deer (CI95 16.3-61.2) yielded MTC concentrations >10(3) CFU/g or mL (referred here as super-shedders). Red deer have a significantly higher risk of being super-shedders compared to wild boar (OR = 11.8, CI95 2.3-60.2). The existence of super-shedders among the naturally infected population of wild boar and red deer is thus reported here for the first time and MTC DNA concentrations greater than the minimum infective doses were estimated in excretion samples from both species.
authors.affiliation: Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal. nunosantos@ecsaude.uminho.pt.|ICVS/3B's, PT Government Associate Laboratory, Braga, Portugal. nunosantos@ecsaude.uminho.pt.
authors.forename: Nuno
authors.initials: N
authors.lastname: Santos
authors.affiliation: Centro de Investigação Interdisciplinar em Sanidade Animal (CIISA), Faculdade de Medicina Veterinária, Universidade de Lisboa (FMV-ULisboa), Lisbon, Portugal. vsa@fmv.ulisboa.pt.
authors.forename: Virgílio
authors.initials: V
authors.lastname: Almeida
authors.affiliation: SaBio (Health and Biotechnology), IREC, National Wildlife Research Institute (CSIC-UCLM-JCCM), Ciudad Real, Spain. christian.gortazar@uclm.es.
authors.forename: Christian
authors.initials: C
authors.lastname: Gortázar
authors.affiliation: Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal. mcorreianeves@ecsaude.uminho.pt.|ICVS/3B's, PT Government Associate Laboratory, Braga, Portugal. mcorreianeves@ecsaude.uminho.pt.
authors.forename: Margarida
authors.initials: M
authors.lastname: Correia-Neves
mesh_terms: D000818:Animals; D057138:Bacterial Shedding; D003670:Deer; D009169:Mycobacterium tuberculosis / Q000502:physiology*; D011174:Portugal; D034421:Sus scrofa; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology*; D014376:Tuberculosis / Q000382:microbiology / Q000662:veterinary*