Retrospective and prospective perspectives on zoonotic brucellosis

Abstract

Members of the genus Brucella are pathogenic bacteria exceedingly well adapted to their hosts. The bacterium is transmitted by direct contact within the same host species or accidentally to secondary hosts, such as humans. Human brucellosis is strongly linked to the management of domesticated animals and ingestion of their products. Since the domestication of ungulates and dogs in the Fertile Crescent and Asia in 12000 and 33000 ya, respectively, a steady supply of well adapted emergent Brucella pathogens causing zoonotic disease has been provided. Likewise, anthropogenic modification of wild life may have also impacted host susceptibility and Brucella selection. Domestication and human influence on wild life animals are not neutral phenomena. Consequently, Brucella organisms have followed their hosts’ fate and have been selected under conditions that favor high transmission rate. The “arm race” between Brucella and their preferred hosts has been driven by genetic adaptation of the bacterium confronted with the evolving immune defenses of the host. Management conditions, such as clustering, selection, culling, and vaccination of Brucella preferred hosts have profound influences in the outcome of brucellosis and in the selection of Brucella organisms. Countries that have controlled brucellosis systematically used reliable smooth live vaccines, consistent immunization protocols, adequate diagnostic tests, broad vaccination coverage and sustained removal of the infected animals. To ignore and misuse tools and strategies already available for the control of brucellosis may promote the emergence of new Brucella variants. The unrestricted use of low-efficacy vaccines may promote a “false sense of security” and works towards selection of Brucella with higher virulence and transmission potential.

Brucelosis: zoonosis de importancia en México

“…Así mismo, la Dra. Evans indicó que esta enfermedad de los animales de crianza, no ocasionaría contagio alguno al humano, si se consumiera su leche pasteurizada 7 . Feusier y Meyers en 1920, nombraron al género Brucella en honor a Sir David Bruce, microbiólogo y patólogo escocés que identificó al microorganismo por primera vez.…”

“…El consumo de estos productos es histórico, pues la leche es una fuente de proteínas utilizada por la humanidad desde tiempos remotos 7 . Los derivados lácteos se producen generalmente en las zonas rurales; sin embargo, también son comercializados en diferentes zonas urbanas, por lo que los casos de brucelosis no sólo se restringen a las zonas rurales.…”

Comparisons of brucellosis between human and veterinary medicine

“…In honoring Sir Bruce, genus-nomenclature was standardized to Brucella melitensis and Brucella abortus , respectively [7]. Clinical human and animal brucellosis carries a plethora of synonyms including: undulant fever, Malta fever, Mediterranean fever, contagious abortion, Bang’s disease, Neapolitan fever, Crimean fever, and Corps disease [8]. A majority of these names are still used in varying parts of the world.…”

“…Zoonotic potential is classified as pathogenicity and virulence in human hosts. Original citation indicates the original publication where the species was characterized.SpeciesNatural hostZoonotic Potential [8]Original Citation B. melitensis Sheep, goats, and camelsYes – High[5] B. abortus Cattle, elk, and bisonYes – High[6] B. suis Pigs, hare, reindeer/caribouYes – High[122] B. canis Dogs (domestic and wild)Yes – Moderate[123] B. ovis SheepNo reported infections[124] B. neotomae Desert wood ratsNo reported infections[125] B. ceti CetaceansYes – Low[126] B. pinnipedialis PinnipedsYes – Low B. microti Red foxes and common volesNo reported infections[127] B. inopinata UnknownYes – High[2,128] B. papionis Non-Human PrimatesNo reported infections[129,130] B. vulpis Red foxNo reported infections[131,132] Brucella NFXXXX Australian ratNo reported infections[133,134]…”

Posibles casos de tuberculosis y brucelosis en poblados argáricos de Galera (Granada)

“…del yacimiento de Sterkfontein en Sudáfrica (D´Anastasio et al 2009). No obstante el desarrollo de la afección en humanos está estrechamente vinculado con los inicios de la domesticación animal y su aprovechamiento y consumo de productos derivados (Moreno 2014).…”