Brucellosis in small ruminant: seroprevalence, risk factors, and distribution in the southeast of Algeria.

The impact of brucellosis on public health and economy is unquestionable in developing countries such as the case of Algeria. This study aimed to provide further understanding of epidemiological status of brucellosis in small ruminant flocks in the southeast of Algeria. Therefore, a cross-sectional study was conducted among small ruminant flocks (n = 51) in El Oued district using simple random sampling strategy. The serum samples collected from 612 sheep and goats (sheep = 280, goats = 332) were screened for Brucella antibodies using the Rose Bengal test (RBT) and the indirect enzyme-linked immunosorbent assay (iELISA) in parallel on all the serum samples. The seropositive serum samples of both tests were confirmed with the complement fixation test (CFT). A structured questionnaire regarding animal, herd, and farm management was prepared and completed in parallel to sampling. Association between variables and Brucella spp. seropositivity status of herds was assessed by univariate and multivariate analysis using simple and binary logistic regression. Estimated true herd prevalence was 27.95% (95% CI, 17.18-42.01), and true individual prevalence was 3.98% (95% CI, 2.51-6.03). Seropositive herds were detected in bordering areas and regions with the highest livestock density. Occurrence of abortions in herds (p = 0.03) increased at least five times (5) the odds of being seropositive (OR, 6.25; 95% CI, 1.20-32.46). Poultry presence in farms revealed to be a protective factor (p = 0.01) (OR, 0.11; 95% CI, 0.02-0.61). The high-level seroprevalence quantified in this study in small ruminant flocks reflects the persistent animal infection endemicity and the high risk of human exposure.

Seroprevalence and molecular characterization of Chlamydia abortus in frozen fetal and placental tissues of aborting ewes in northeastern Algeria.

Enzootic abortion of ewes is one of the most serious health problems in sheep flocks worldwide. It has a significant economic impact because abortion, decrease in milk production and weak lambs. Besides, the bacteria is zoonotic. A cross-sectional study was conducted to determine the seroprevalence and risk factors associated with Chlamydia abortus infection in 552 ewes in Constantine using a C. abortus-specific indirect ELISA kit. Chlamydial DNA was investigated in ten ovine fetuses and eight placentas using PCR- restriction fragment length polymorphism (RFLP) and DNA sequencing. The study concluded that 7.2 % of ewes were seropositive and 33.3 % of sheep flocks had at least one seropositive ewe. Adjacent farmworker visits (OR = 7.667, 95 % CI (OR) = 2.307; 27.203) was defined as a risk factor. Deliveries of weak lambs (OR = 2.920, 95 % CI (OR) = 1.022; 8.342) and septicemia in lambs (OR = 9.971, 95 % CI (OR) = 2.383; 41.713) were significantly associated with chlamydial infection. PCR-RFLP analysis revealed positive signals to C. abortus in six fetuses and four placentas. Sequencing of the omp2 gene revealed that the Algerian strain is 96 % similar with C. abortus FAS strain. C. abortus plays a major role in abortion in northeastern Algeria. Appropriate control measures must be implemented to reduce economic losses and to avoid human contamination.

Seroprevalence and risk factors associated with Chlamydophila spp. infection in ewes in the northeast of Algeria.

A cross-sectional study was carried out to estimate prevalence of Chlamydophila spp. antibodies and to investigate risk factors associated with chlamydial infection in 552 ewes between March 2011 and January 2012 in the province of Constantine. Anti-Chlamydophila antibodies were detected using an indirect enzyme-linked immunosorbent assay kit in 24.5% of examined sera. Of the herds, 70.4% had at least one seropositive animal. A pretested structured questionnaire was administered in order to collect information on individual animal health and herd management practices. Chi-square analysis and multivariable logistic regression model were used to identify risk factors related to Chlamydophila seropositivity. Univariable analysis revealed 17 variables with p < 0.25 that were offered to the multivariable logistic regression model which in turn identified 12-23 months age group (OR = 5.903, 95% CI (OR) = 1.690; 20.618) and not using disinfectants (OR = 2.099, 95% CI (OR) = 1.314; 8.065) as risk factors for Chlamydophila spp. seropositivity. Moreover, occurrence of stillbirth problem (OR = 3.682, 95% CI (OR) = 1.825; 7.430) and 5-10% mortality rate in young lambs (OR = 2.584, 95% CI (OR) = 1.058; 6.310) were significantly associated with seropositivity to Chlamydophila spp. On the other hand, availability of veterinary service was identified as a protective factor (OR = 0.161, 95% CI (OR) = 0.051; 0.511).