Abstract

Background:
Chlamydia abortus (C. abortus) remains a notable zoonotic pathogen, primarily responsible for abortion in sheep and goats. Despite its veterinary and zoonotic concern,

Aim:
This study aimed to assess the prevalence of Chlamydia abortus in human and animals in the northern and coastal part of Egypt, and the their associated risk factors

Methods:
A total of 196 blood samples of apparently healthy and aborted sheep collected from different herds located in three Egyptian governorates. In addition, a total of 242 blood samples were collected from women with a history of abortion admitted at El Shatby Hospital in Alexandria, Egypt. Collected samples were tested serologically for specific anti-C. abortus antibodies using enzyme-linked immunosorbent assay (ELISA) employing major outer-membrane protein (MOMP) peptide followed by investigation of various risk factors.

Results:
Interestingly, Chlamydia abortus IgG antibodies could be detected in 12.2% of the examined sheep. Regarding the sociodemographic characteristics, five risk factors were found significantly associated with anti-C. abortus IgG antibody positivity in sheep: breed (X2 = 27.543; P = 0.000), governorate (X2 = 33.564; P = 0.000), breeding system (X2 = 24.298; P = 0.000), pregnancy status (P = 0.003), and history of abortion (P = 0.000). On the other side, anti-C. abortus IgM antibodies could be detected in aborted women's sera at a rate of 13.2%. By conducting Pearson Chi-Square, statistically significant association was detected between the infection in aborted women and residence (X2 = 27.428; P= 0.000), contact with sheep (X2 = 77.744; P= 0.000), history of miscarriage (X2 = 22.044; P= 0.000), and time of miscarriage (X2 = 54.550; P= 0.000).

Conclusion:
This study is the first to address the seroprevalence of C. abortus in humans and the potential risk factors associated with the exposure in northern and coastal Egyptian regions. Furthermore, it provides an updated overview of the seroprevalence of this zoonotic pathogen among sheep in Northern Egypt.

Key words: Chlamydia abortus; Aborted women; Sheep; IgG; IgM; Risk factors.