Prevalence of Coxiella burnetii antibodies in ruminant raw milk and a comparative meta-analysis in Egypt
Abstract
Background: Q fever is a zoonotic bacterial infection caused by Coxiella burnetii that affects many animal species and humans. The infection induces economic losses in the ruminant industry and has public health concerns due to abortions. Aim: This study aimed to estimate the prevalence of C. burnetii antibodies in individual raw milk samples from different lactating or dairy ruminants in Egypt using a commercial enzyme-linked immunosorbent assay (ELISA). Additionally, this study aims to review and meta-analyze the epidemiological data of this pathogen in animals across the country. Methods: Samples were collected from Qena governorate in southern Egypt and Dakahlia governorate in northern Egypt, where data in these regions were underestimated. A systematic electronic search was conducted to gather all the previously published studies on the prevalence of C. burnetii in different animals, and data were extracted and subjected to meta-analysis. Results: An overall seroprevalence of 6.3% (13/205) was estimated for all animals. The seropositive rates were 4.3% (7/164), 0% (0/14), 25% (4/16), and 18.2% (2/11) in tested female cattle, buffaloes, sheep, and goats, respectively. Of the 154 cattle milk samples collected from Qena, 6 (3.9%) were positive, while 1 (10%) out of 10 was positive in Mansoura. No significant differences were detected based on the age and location of the sampled cattle. A meta-analysis of previously published studies revealed a pooled seroprevalence of 21.6%–28.8% in ruminants, based on enzyme-linked immunosorbent assay. In contrast, higher infection rates were estimated based on PCR assays, with pooled prevalences of 48.8%, 45.8%, 36.5%, and 34.4% for sheep, goats, cattle, and buffaloes, respectively. Conclusion: This study provides valuable and novel data on the seroprevalence of C. burnetii antibodies in milk samples from different ruminants and regions of Egypt. This study also provides an overview of C. burnetii infections in Egypt, emphasizing the need for effective control strategies against this pathogen.