Adverse Pregnancy Outcomes and Coxiella burnetii Antibodies in Pregnant Women, Denmark - Volume 20, Number 6—June 2014 - Emerging Infectious Disease journal - CDC
Volume 20, Number 6—June 2014
Adverse Pregnancy Outcomes and Coxiella burnetiiAntibodies in Pregnant Women, Denmark
Stine Yde Nielsen , Kåre Mølbak, Tine Brink Henriksen, Karen Angeliki Krogfelt, Carsten Schade Larsen, and Steen Villumsen
Author affiliations: Aarhus University Hospital, Aarhus, Denmark (S.Y. Nielsen, T.B. Henriksen, C.S. Larsen); Statens Serum Institut, Copenhagen, Denmark (K. Mølbak, K.A. Krogfelt, S. Villumsen)
Q fever is a zoonotic infection caused by Coxiella burnetii. Findings of adverse pregnancy outcome in infected women, high seroprevalence in animal studies, and large human outbreaks have placed increasing focus on Q fever in several European countries, including Denmark (1–4). In ruminants, infection with C. burnetii is associated with high numbers of bacteria in the placenta, and the infection is known to cause abortion, retained placenta, endometritis, and infertility (5,6). Humans are infected with C. burnetii predominantly by inhalation of contaminated aerosols, and persons who have contact with livestock are at highest risk for exposure (7). Among pregnant women, >90% of those who show antibodies for C. burnetii that suggest recent infection may remain asymptomatic (8). Case series from France have associated symptomatic and asymptomatic C. burnetii infection during pregnancy with obstetric complications, including miscarriage, preterm delivery, and fetal death (9–11). In contrast, population studies from northern Europe have not found an association between C. burnetii and adverse pregnancy outcomes (12–15).
Cattle are the main reservoir for C. burnetii in Denmark. A recent study of the seroprevalence ofC. burnetii in cattle found that bulk-tank milk samples tested positive for C. burnetii at 59 of 100 randomly selected farms (16). In addition, the reported prevalence of antibodies to C. burnetiiamong veterinarians in Denmark ranges from 36% to 47% (1,2,17). These findings show that exposure to C. burnetii is common in this country in the animal reservoir and in those who are occupationally exposed to livestock or who live in rural areas with livestock contact. However, the risk for and implications of infection with C. burnetii among pregnant women have not been exhaustively described (12,15). Because of this, and because findings from the case series in France conflict with results from population-based studies from the Netherlands and Denmark, we reviewed national data from Aarhus University Hospital, Aalborg University Hospital, Hospital of Southwest Jutland, Viborg Regional Hospital, Regional Hospital West Jutland, and Hilleroed Hospital in Denmark to identify women who had elevated antibodies to C. burnetii during pregnancy. We evaluated the course of infection, effects of treatment with cotrimoxazole (trimethoprim-sulfamethoxazole), and pregnancy outcomes for these women.
Dr Nielsen is a physician in the Department of Clinical Microbiology, Aarhus University Hospital, and a postdoctoral scholar at the Department of Occupational Medicine, Hospital Region West, Herning, Denmark. Her research interests include infections, obstetrics, pediatrics, and microbiology.
- Table 1. Patient characteristics and pregnancy outcomes in 12 women who had positive Coxiella burnetii titers during pregnancy, Denmark
- Table 2. Results of testing for 12 women who had positive Coxiella burnetii titers during pregnancy, Denmark
Suggested citation for this article: Nielsen SY, Mølbak K, Henriksen TB, Krogfelt KA, Larsen CS, Villumsen S. Adverse pregnancy outcomes and Coxiella burnetii antibodies in pregnant women, Denmark. Emerg Infect Dis [Internet]. 2014 Jun [date cited].http://dx.doi.org/10.3201/eid2006.130584