pathogenesis, clinical manifestations, treatment, and prevention of brucellosis in humans and animals

Brucella genus is a gram-negative coccobacillus that causes a zoonotic disease called brucellosis in humans and animals. brucellosis is transmissible, and there are different types of transmission, such as animal-to-human (dairy and meat consumption), human-to-human (placenta, breastfeeding, sexual intercourse, blood transfusion, and bone marrow transplantation), and animal-to-animal (aerosol-containing brucella, placenta, and sexual intercourse). due to having virulence factors such as type iv secretion system (t4ss), superoxide dismutase enzyme, bvrs/bvrr two-component system, lps with o chain, and cyclic beta-glucan, brucella can survive and replicate intracellularly and cause disease. the t4ss helps brucella survive intracellularly by sending effectors into the host cell. fever, excessive sweating, malaise, myalgia, arthralgia, loss of appetite, weight loss, hepatosplenomegaly, spondylitis, and arthritis are the clinical manifestations of brucellosis in humans. in animals, complications such as abortion, weak calf birth, reduced fertility, endometritis, reduced milk production, orchitis, epididymis, and hygroma may be observed. animals with brucellosis are not treated and are slaughtered. no vaccine against brucellosis has been approved for humans yet. but for animals, s19, rev.1, s2, rb51, and sr82 vaccines are used for prevention. development and approval of brucellosis vaccines for humans, wider use of animal vaccines, and timely diagnosis of suspected cases will help to better control brucellosis and prevent economic consequences.