Brucella suis

Pictures

Picture	Title	Caption	Copyright
Title Field symptoms Caption brucellosis (Brucella suis); symptoms. Sow with her new litter of piglets. Some of the newborn are dead, and others are sickly, due to a case of brucellosis, caused by the bacterium, Brucella suis. Swine brucellosis causes abortion, reduced milk production, and infertility. USA. Copyright Public Domain - Released by the Centers for Disease Control and Prevention/Public Health Image Library (PHIL) - CC0	Field symptoms	brucellosis (Brucella suis); symptoms. Sow with her new litter of piglets. Some of the newborn are dead, and others are sickly, due to a case of brucellosis, caused by the bacterium, Brucella suis. Swine brucellosis causes abortion, reduced milk production, and infertility. USA.	Public Domain - Released by the Centers for Disease Control and Prevention/Public Health Image Library (PHIL) - CC0
Title Brucella suis bacteria Caption brucellosis (Brucella suis); Processed using the Gram-stain method, this photomicrograph revealed the presence of numerous Gram-negative, coccobacillus, Brucella suis bacteria. Copyright Public Domain - Released by the Centers for Disease Control and Prevention/Public Health Image Library (PHIL)/original image by Dr. W.A. Clark-1977 - CC0	Brucella suis bacteria	brucellosis (Brucella suis); Processed using the Gram-stain method, this photomicrograph revealed the presence of numerous Gram-negative, coccobacillus, Brucella suis bacteria.	Public Domain - Released by the Centers for Disease Control and Prevention/Public Health Image Library (PHIL)/original image by Dr. W.A. Clark-1977 - CC0

Identity

Preferred Scientific Name

• Brucella suis Huddleston

Taxonomic Tree

• Domain: Bacteria
•     Phylum: Proteobacteria
•         Class: Alphaproteobacteria
•             Order: Rhizobiales
•                 Family: Brucellaceae
•                     Genus: Brucella
•                         Species: Brucella suis

Diseases Table

Distribution Table

The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.

Pathogen Characteristics

The survival of Brucella under environmental conditions is a relatively important factor in the transmission of disease. The survival rate of Brucella is similar to other non-sporing Gram-negative bacteria and as such is extremely variable depending on prevailing conditions. Experimental evidence indicates that B. suis is readily killed by pasteurisation, 2-4 hours of direct sunlight, and the most commonly used disinfectants. Brucella can survive in organic matter at freezing or near-freezing temperatures in excess of 2 years. Consequently, efforts to eliminate brucellosis from pig farms must include an effective sanitation program (Luchsinger et al., 1965).

The understanding of the pathogenesis of brucellosis has increased substantially in recent years (for reviews see Poester et al., 2013; Olsen et al., 2014; de Figueiredo et al., 2015) although there remain significant gaps in knowledge. Brucella can invade through epithelial cells of its host and once invaded through the digestive or respiratory tract is capable of surviving intracellularly within phagocytic or non-phagocytic host cells. The mechanisms of cell invasion are not clear and specific host receptors have not been identified but invasion through the digestive tract elicits no host inflammatory response so Brucella invade silently unnoticed by the innate immune response of the host. Brucellae lack classical virulence factors, but lipopolysaccharide (LPS) plays a major role as it prevents complement mediated bacterial killing and provides resistance against antimicrobial peptides such as defensins and lactoferrin. Brucella LPS has weak endotoxic properties compared to other bacteria, allowing the organism to escape detection by Toll-like receptors of the innate immune system. Brucella interact with cholesterol-rich microdomains (lipid rafts) within the plasma membrane mediating internalisation into host cells.

Once Brucella have entered cells they interfere with intracellular trafficking preventing fusion of the Brucella containing vacuole (BCV) with lysosome markers and directing the BCV towards a rough endoplasmic reticulum (RER) containing compartment highly permissive to intracellular replication of Brucella and the establishment of chronic infection. One of a number of systems known to be important for virulence is the BvrR/BvrS two component regulator which is required for modulation of host cell cytoskeleton on Brucella invasion. Cylic β-1,2 glucans are constituents of the bacterial periplasm with osmoregulatory and cholesterol sequestering activity required for intracellular survival. They prevent phagosome maturation by interfering with lipid rafts and preventing fusion of lysosomes with the BCV. Brucella also express a type IV secretion system encoded by the virB operon that is induced intracellularly in macrophages (Boschiroli et al., 2002) and is crucial for intracellular survival and virulence of B. suis .B. suis virB mutants cannot survive and multiply in macrophages or epithelial cells (O’Callaghan et al., 1999).

Host Animals

References

Boschiroli ML; Ouahrani-Bettache S; Foulongne V; Michaux-Charachon S; Bourg G; Allardet-Servent A; Cazevieille C; Liautard JP; Ramuz M; O'Callaghan D, 2002. The Brucella suis virB operon is induced intracellularly in macrophages. Proceedings of the National Academy of Sciences of the United States of America, 99(3):1544-1549.

Figueiredo Pde; Ficht TA; Rice-Ficht A; Rossetti CA; Adams LG, 2015. Pathogenesis and immunobiology of brucellosis : review of Brucella-host interactions. American Journal of Pathology, 185(6):1505-1517. http://www.sciencedirect.com/science/article/pii/S0002944015001832

Luchsinger DW; Anderson RK; Werring DF, 1965. A swine brucellosis epizootic. J. Am. Vet. Med. Assoc., 147:632-636.

O'Callaghan D; Cazevieille C; Allardet-Servent A; Boschiroli ML; Bourg G; Foulongne V; Frutos P; Kulakov Y; Ramuz M, 1999. A homologue of the Agrobacterium tumefaciens VirB and Bordetella pertussis Ptl type IV secretion systems is essential for intracellular survival of Brucella suis. Molecular Microbiology, 33(6):1210-1220.

OIE Handistatus, 2005. World Animal Health Publication and Handistatus II (data set for 2004). Paris, France: Office International des Epizooties.

Olsen SC; Palmer MV, 2014. Advancement of knowledge of Brucella over the past 50 years. Veterinary Pathology, 51(6):1076-1089. http://vet.sagepub.com/content/51/6/1076.short

Poester FP; Samartino LE; Santos RL, 2013. Pathogenesis and pathobiology of brucellosis in livestock. Revue Scientifique et Technique - Office International des Épizooties, 32(1):105-115.

Distribution References

CABI Data Mining, 2001. CAB Abstracts Data Mining.,

OIE Handistatus, 2005. World Animal Health Publication and Handistatus II (dataset for 2004)., Paris, France: Office International des Epizooties.

Distribution Maps