Investigation of Coxiella burnetii prevalence in women who had miscarriage and their spouses by serological and molecular methods

Coxiella burnetii is the causative agent of the common zoonotic disease known as Q fever. Human infection is mostly maintained by inhalation of contaminated aerosols that originate from infected birth products, milk and urine. Sexual transmission has also been reported. In pregnant women the disease causes abortion during the first trimester, while at later stages it tends to become chronic causing low birth weight babies and premature birth. The aim of this study was to investigate the prevalence of C.burnetii in women who had miscarriages, their spouses and in a control group composed of women with normal delivery by using serological and molecular methods. A total of 89 cases (58 female, 31 male; age range: 21-64 years, mean age: 33.1 ± 7.6 years) were included in the study. Women who had abortion (n= 36) were recruited along with their husbands (n= 31), and 22 women who had normal pregnancy were accepted as controls. Blood and placental tissue samples (after abortion or normal delivery) were collected from all of the female subjects, while blood samples were collected from the males. C.burnetii IgG and IgM antibodies in the sera of patients and controls were analysed by ELISA and indirect fluorescein antibody (IFA) methods, and the presence of C.burnetii DNA was searched in whole blood and placenta samples by using polymerase chain reaction (PCR). In our study, C.burnetii Phase II IgG antibody positivity rates in women who had miscarriages, their spouses and in women with normal delivery were found as 27.8% (10/36), 38.7% (12/31) and 4.5% (1/22), respectively by ELISA, while those rates were detected as 27.8% (10/36), 41.9% (13/31) and 9.1% (2/22), respectively by IFA which was accepted as the reference method. However C.burnetii Phase I IgM, Phase I IgG and Phase II IgM antibodies were not detected in none of the subjects by both methods. The relatively high seropositivity rate in our study group (25/89; 28.1%) was thought to be associated with high rates of livestock breeding in our region. Although C.burnetii IgG seropositivity rate in in women who had miscarriages was higher than women with normal delivery, the difference was not found to be statistically significant (x2= 2.906, p= 0.088). When the results of the women with miscarriages and their spouses were evaluated together, it was detected that C.burnetii IgG antibodies were not determined in the spouses of four seropositive women (two positive with 1/64, two with 1/128 titer); titer was 1/64