MERS-CoV Infection in a Pregnant Woman in Korea

Jeong, Soo Young; Sung, Se In; Sung, Ji-Hee; Ahn, So Yoon; Kang, Eun-Suk; Chang, Yun Sil; Park, Won Soon; Kim, Jong-Hwa

Currently, an exposure time to this virus during pregnancy and a severity of maternal disease could be expected to affect the perinatal outcome. However, there is limited knowledge about the clinical implications of MERS-CoV infection on the maternal, fetal, and placental aspects of pregnancy. From the maternal aspect, there is no epidemiologic data regarding whether pregnant women are more susceptible to MERS. Also, it is unknown whether MERS-CoV infected pregnant women have a more severe disease course compared with the non-pregnant population. In our case, she showed a mild disease course. She had low level of IgG antibody by ELISA and IIFT but not detectable neutralization activity by PRNT. It has been suggested that neutralizing antibodies are produced at low levels and are potentially short-lived after mild or asymptomatic MERS-CoV infection (16, 17) . From the fetal aspect, it is unclear whether MERS was a causative factor in the stillbirth or preterm birth. Fetal specimen and/or placenta were not available for evaluation in the previous cases. As pregnancy alters maternal pulmonary function and consumes more oxygen, severe respiratory illness during pregnancy results in maternal hypoxemia. Maternal hypoxemia can be associated with poor fetal oxygenation, which eventually could lead to preterm birth or stillbirth. Also, altered immune responses during pregnancy could affect the fetal outcome (13) . From the placental aspect, there have been no reports of MERS causing pathology of the placenta including infarction, insufficiency, or villus placentitis. Our case showed placenta abruption clinically, which can be caused by maternal infection. There is no evidence of a relationship between MERS-CoV and placenta disorder. However, the possibility that this virus may be a cause of placenta abruption should be of concern.