Humoral IgG responses persist after the peak of the response (3-4 weeks post-infection) and remain detectable over long periods of time (up to several years); in contrast, the IgM response is rapidly induced 2-3 weeks after exposure and may disappear after a few months (37,43,44)

Humoral IgG responses persist after the peak of the response (3-4 weeks post-infection) and remain detectable over long periods of time (up to several years); in contrast, the IgM response is rapidly induced 2-3 weeks after exposure and may disappear after a few months (37,43,44). infection is essential for analyzing serological results correctly and may help to predict abortion. Indirect ELISAs MGC5276 help to discriminate 1) between false positive serological reactions and true brucellosis and 2) between vaccination and infection. Biotyping ofBrucellaspp. provides valuable epidemiological information that allows tracing an infection back to the sources in instances where several biotypes of a givenBrucellaspecies are circulating. Polymerase chain reaction and Ticlopidine HCl new molecular methods are likely to be used as routine typing and fingerprinting methods in the coming years. == Conclusion == The diagnosis of brucellosis in livestock and wildlife is complex and serological results Ticlopidine HCl need to be carefully analyzed. TheB. abortusS19 andB. melitensisRev. 1 vaccines are the cornerstones of control programs in cattle and small ruminants, respectively. There is no vaccine available for pigs or for wildlife. In the absence of a human brucellosis vaccine, prevention of human brucellosis depends on the control of the disease in animals. Brucellae are Gram-negative, facultative intracellular bacteria that can infect many species of animals and man. Ten species are recognized within the genusBrucella. There are 6 classical species:Brucella abortus,Brucella melitensis,Brucella suis,Brucella ovis,Brucella canis, andBrucella neotomae(1,2). This classification is based mainly on differences in pathogenicity and host preference (3). Distinction between species and between biovars of a given species is currently performed using differential tests based on phenotypic characterization of lipopolysaccharide (LPS) antigens, phage typing, dye sensitivity, requirement Ticlopidine HCl for CO2, H2S production, and metabolic properties (1,2). The main pathogenic species worldwide areB. abortus, responsible for bovine brucellosis;B. melitensis, the main etiologic agent of ovine and caprine brucellosis; andB. suis,responsible for swine brucellosis. These 3Brucellaspecies cause abortion (abortion storm in naive heifers), and when brucellosis is detected Ticlopidine HCl in a herd, flock, region, or country, international veterinary regulations impose restrictions on animal movements and trade, which result in huge economic losses. These are the reasons why programs to control or eradicate brucellosis in cattle, small ruminants, and pigs have been implemented worldwide (4). B. ovisandB. canisare responsible for ram epididymitis and canine brucellosis, respectively. In the case ofB. neotomae,only strains isolated from desert wood rat (Neotoma lepida) in North America have been reported. Recently 4 newBrucellaspecies have been described:Brucella pinnipedialisandBrucella ceti, isolated predominantly from seals and cetaceans, respectively (5);Brucella microti, isolated from common voles (Microtus arvalis) (6), soil (7), and foxes (Vulpes vulpes) (8); andBrucella inopinata, isolated from a breast implant (9). There is a general host restriction pattern among the differentBrucellaspecies, meaning that differentBrucellaspecies infect different preferred hosts. Even within theB. suisspecies, different biovars preferentially infect different animal host species (1-3). Indeed,B. suisbiovars 1 and 3 infect suidae, biovar 2 infects suidae and hare (Lepus europeanus), biovar Ticlopidine HCl 4 infects reindeer (Rangifer tarandus tarandus) and caribou (Rangifer tarandus granti), and biovar 5 has been isolated from rodents in Russia. AllBrucellaspecies may also infect wildlife species. ClassicalBrucellaspecies have been isolated from a great variety of wildlife species such as bison, elk, feral swine, wild boar, fox, hare, African buffalo, reindeer, and caribou (10). In order to implement appropriate control measures to address wildlife brucellosis, it is very important to distinguish between a spill-over of infection contracted from domestic animals and a sustainable infection (10). In the latter case, the concern of the livestock industry is to prevent the re-introduction of the infection in livestock (spill-back), particularly in regions or states that are officially brucellosis-free. If the status of officially brucellosis-free is lost, domestic animals must be tested prior to being traded, which imposes huge costs. This is exemplified by recent episodes of cattle being infected withB. abortustransmitted by elk in the Greater Yellowstone Area in the USA (11) and of outdoor reared pigs infected withB. suisbiovar 2 transmitted by wild boar in France (12). Brucellosis is an established zoonosis: infections have been attributed to at least 5 of the 6 classicalBrucellaspecies in terrestrial mammals. Studies from around the world indicate that elimination of the animal brucellosis reservoir has resulted in a substantial decline in the incidence of human disease (13). Currently, laboratory.