Impact of Zika and Chikungunya Viruses on Spontaneous Abortions: Insights from a Reference Maternity Hospital

To investigate the association between miscarriage and ZIKV and CHIKV infection. The study population consisted of pregnant women who had miscarriages between 2015, 2016 and 2017, comprising a total of 30 women who were treated at the Santa Casa de Misericórdia do Pará Foundation (FSCMPA). The processed samples came from already paraffinized material containing placental and fetal remains, where they were tested with hematoxylin-eosin and immunohistochemistry for ZIKV and CHIKV. Regarding the sociodemographic, clinical and obstetric characteristics of the patients, they correspond to the age group between 20 and 29 years of age; of brown color; women who had abortions for the first time; miscarriages occurring in the first trimester of pregnancy; women belonging to the metropolitan region of Belém; diagnosed with incomplete abortion and who had undergone uterine curettage procedure. Regarding the histopathologic and immunohistochemical findings, an inflammatory infiltrate rich in neutrophils and lymphocytes, among others, was found in the endometrial fragments and chorionic membranes. In addition, placental areas consisting of edema, necrosis and hemorrhage were found. The study identified ZIKV and CHIKV in 40% (n = 12) of samples from spontaneous abortion specimens, and CHIKV was the most prevalent virus in the study, representing 36.11% of the total specimens, with reddish granular material in the cytoplasm of decidua cells and placental villi suggesting that the viruses may be present in these regions of the placenta.