Como Muestrear Ganado para Brucelosis - Todo sobre Brucelosis - TvAgro por Juan Gonzalo Angel

Twitter @juangangel Bovine brucellosis, known as infectious abortion, bovine abortion, Bang's disease, and in humans as Malta fever, is an infectious, contagious, zoonotic disease widely distributed worldwide. It is caused by bacteria of the Brucella genus and is characterized by abortions in the last third of gestation, the birth of weak offspring, retained placentas, and infertility problems (Enright 1990). The bacteria enters the body through oral, conjunctival, and dermal routes, with the ingestion of fecal matter and contaminated grasses, as well as contamination of the udder during milking, being particularly important. Congenital infection has also been confirmed. This disease compromises the competitiveness of production by reducing reproductive and productive efficiency. Furthermore, the risk this disease poses to public health must be considered, as it is a zoonotic disease. The Brucellosis and Tuberculosis Free Farms Program is currently being implemented in Colombia by the Colombian Agricultural Institute (ICA) with the support of several organizations, including Asocebu. ETIOLOGY The causative agent of brucellosis is a bacterium of the Brucella genus, of which there are 7 species: Brucella abortus, which infects cattle, dogs, and humans; Brucella mellitensis, which infects goats, cattle, dogs, and humans; Brucella cannis, which infects canines and humans; Brueilla ovis, which infects sheep; Brucilla suis, which infects pigs, dogs, and humans; Brucella maris, which infects marine mammals; and Brucella neotomae, which infects rodents. EPIDEMIOLOGY It is a disease with a worldwide distribution, with significant geographic variations in incidence and prevalence. The areas with the highest prevalence are the Mediterranean region, Western Asia, parts of Africa, and the Americas, where the disease is present in most countries. The most widespread species are B. melitensis, followed by B. abortus and B. suis. The main route of transmission is through the digestive tract. This occurs when animals lick aborted fetuses, newborn calves, and/or the genitals of other animals. These animals excrete large quantities of bacteria along with the tissues and secretions from the abortions. This causes a massive bacterial infection, thus contaminating the soil, pens, bedding (husks, straw, sawdust), and water sources. Brucella is able to survive in the environment for long periods of time. The ingestion of food and drink contaminated with vaginal secretions and milk from infected females is also important. PATHOGENESIS Species of the Brucella genus are facultative intracellular pathogens, a property that protects them from the action of antibiotics and immune system antibodies. This explains the chronic nature of the disease, as the bacteria are able to adhere to, penetrate, and multiply in a wide variety of cells of infected species. When the bacteria enter the body, they are attacked by immune system cells that destroy them internally. If they are not destroyed, they travel through the lymphatic ducts and reach regional lymph nodes, where they are distributed via the bloodstream to the rest of the body. They have a particular tropism for the placenta, as it produces some metabolites essential for the development of the bacteria in this organ. DIAGNOSIS The definitive diagnosis of the infection is established by isolating the bacteria in blood, bone marrow, or other tissue cultures. Serological methods only provide a presumptive diagnosis. DIRECT METHODS These are based on detecting the presence of the bacteria or its components in animal or human tissues. The definitive diagnosis requires isolation of the bacteria, which can take between 7 and 30 days. Polymerase chain reaction (PCR) is also used, but not all countries use it. Juan Gonzalo Angel www.tvagro.tv