Surveillance of tuberculosis in Georgia in 2017

Abstract

Background: Tuberculosis is a chronic zoonotic disease that affects domestic and wild mammals, birds and humans. There are countries, where the disease is huge problem for animal and human health and Georgia is amongst them. The first tuberculosis case in Georgia was registered in the 1925 year. 73 unreliable foci were registered in the 1972 year, the number of unreliable villages decreased during 1985–1995 years. After those years no active surveillance was conducted to identify disease unreliable foci in Georgia. Methods and materials: The aim of the study was to identify tuberculosis positive animals and to determine the prevalence of the disease among herds/villages. 10,000 animals were chosen for testing from dairy cattle farms in 5 risk regions. The number of animals was calculated based on sample size calculation (Confidence level – 95%; population size – 200,000, Expected prevalence 50%, error 1%). Double intradermal tuberculin test (both avian and bovine tuberculin) was administrated to large ruminants above 6 weeks of age. All data (Animal owner name, ID, phone number, address and animal ID, sex, age, date and time of injection) were recorded on standardized forms. The interpretation of reaction was based on clinical observation after 72 h of injection of tuberculin. Results: Totally 9505 large ruminants were tested from 277 households in 23 municipalities. Appeared prevalence was 0.44% (44 positive/9505 tested) on individual level, 5.4% (15 positive/277 tested) on holding level and 6.5% (6 positive/91 tested) on herd/village level. Tuberculosis positive cases were identified in Samtskhe Javakheti (73.8%) Kvemo Kartli (14.3%) and Shida Kartli (11.9%) regions, where the livestock industry is more developed. No positive cases identified in Kakheti and Imereti regions. The highest prevalence on the animal level within the regions was in the Samtskhe Javakeheti region (0.92%) and lowest in the Kvemo Kartli region (0.25%). prevalence between villages varied between 1.67–6.85 percentages (average 4.2%). Conclusion: According to the obtained data, it can be concluded that the animal tuberculosis is still widespread in Georgia, especially in big commercial farms, but prevalence within the animals is low. Most of the villages were new emerged and did not have connections to earlier registered foci.