Haley A Abernathy, Diana Zychowski, Neha Mokashi, Dana Giandomenico, Edward Breitschwerdt, Bonnie Shook-Sa, Lisa Rahangdale, Ross Boyce
Our findings indicate that nearly 1-in-10 (9.2%) pregnant women in central NC have serological evidence of exposure to SFGR, while 1-in-25 (4.1%) have evidence of exposure to Bartonella. Though we did not find evidence of an association between seroreactivity and adverse outcomes, only a small number of individuals with adverse outcomes were seroreactive to either pathogen. Thus, larger samples will be needed to adequately measure the degree of association, if any exists, between perinatal outcomes and seroreactivity.
BACKGROUND AND OBJECTIVES: Spotted fever group Rickettsia (SFGR) and Bartonella henselaeare emerging pathogens with overlapping clinical presentation. Though they are transmitted by different vectors, both possess biologically plausible mechanisms for long-term disruption of vascular signaling and blood vessel function. The goal of this study was to estimate the seroprevalence of B. henselae and SFGR antibodies among pregnant women attending antenatal care clinics in Orange, Chatham, Alamance, Durham, Person, and Caswell Counties of North Carolina. This study also aimed to investigate potential associations between seroreactivity and adverse maternal or perinatal outcomes.
METHODS: Remnant sera were collected from pregnant women undergoing routine antenatal care at UNC Health facilities between March 1, 2020, and June 30, 2022. From the available samples, we generated a representative cohort. Specimens underwent testing for SFGR and B. henselae-specific immunoglobulin G. Adjusted and unadjusted prevalence ratios of adverse outcomes were estimated and stratified by exposure status.
RESULTS: A total of 568 samples were tested. Antibody reactivity against SFGR was present in 9.2% (95% confidence interval [CI]: 6.8 - 11.5%) of the study population, while anti-B. henselae antibody reactivity was detected in 4.1% (95% CI: 2.4 - 5.7%). Adjusted prevalence ratios of adverse perinatal outcomes in seroreactive and nonreactive individuals ranged from 0.89 to 1.22.
CONCLUSIONS: Our findings indicate that nearly 1-in-10 (9.2%) pregnant women in central NC have serological evidence of exposure to SFGR, while 1-in-25 (4.1%) have evidence of exposure to Bartonella. Though we did not find evidence of an association between seroreactivity and adverse outcomes, only a small number of individuals with adverse outcomes were seroreactive to either pathogen. Thus, larger samples will be needed to adequately measure the degree of association, if any exists, between perinatal outcomes and seroreactivity.