Brucellosis (BRUCELLOSIS) etiology. The agents of brucellosis in humans and animals are bacteria that belong to the Brucella. Brucella rnelitensis, or Maltese micrococcus (Bruce), is the causative agent of brucellosis of small ruminants (Sheep, goats): Brucella abortus bovis (Bang) is the causative agent of disease in cattle (mainly cows), and Brucella abortus suis (Traum) causes disease in pigs. Possible migration of Brucella between animals of different species. Brucella similar to each other by structure and differ in their biochemical activity, as well as on the antigenic structure. Brucella reach a diameter of an average of 0.3-0.5 and have a length from 0.5 to 1.5-2.
They have the form of cocci or coccobacillus, gram, easily dyed all aniline dyes: fixed, not form spores, resistant in the environment. In the soil, water, discharges of diseased animals and in food (meat, milk, dairy products) may persist for weeks or months. In ice and snow stored from 1.5 to 4 months or more. Heating to 70 , direct sunlight, hydrochloric acid in the dilution 1: 1000, 0.2% solution of bleach, 5% solution of bleach and 2% solution of Lysol kill Brucella. Growth of Brucella in artificial nutrient media (special stock) is very slow – for 3 weeks and bolee.Epidemiologiya.
The main source of infection for human brucellosis are sick farm animals (usually goats and sheep at least – cattle). Sick animals are contagious especially during pregnancy, lambing, calving, lactation, they often have abortions. From patients with brucellosis Brucella animals stand out in large quantities in the urine, aborted fetuses, uterine discharge, amniotic fluid, milk, sputum. The epidemiological risk of such animals is especially great in helping them with the occurrence of abortion. Infection of human brucellosis is in the care of sick animals, and even more – through food (raw or pasteurized milk, butter, sour cream, cottage cheese, cheese, cooked enough or well-done meat).