Perinatal Transmission of Dengue Virus Type 2 in Northern Argentina: A Series of 6 Cases

Vertical transmission of dengue virus (DENV) may produce a wide range of disease symptoms such as premature birth, low birth weight and miscarriages.

We report and analyze 6 cases of vertical transmission of DENV type 2 in Salta Province, Argentina, during 2023. DENV infection in mothers and newborns was confirmed by the presence of NS1 antigen, viral nucleic acid and/or immunoglobulin M. Epidemiologic and clinical data were collected upon hospital admission, and laboratory parameters were determined during hospitalization.

Most pregnant women exhibited dengue symptoms during the peripartum period, with fever, headache and thrombocytopenia each affecting 66.7% of cases. Three mothers experienced gynecorrhagia. One mother presented with severe dengue and developed pleural effusion. The median time from maternal symptom onset to childbirth was 4 days (interquartile range [IQR] 3-4 days). All neonates were full term with appropriate weight for gestational age, and 4 were females. Three newborns were delivered vaginally, and 3 were delivered by cesarean section. Five cases were symptomatic and presented varied clinical manifestations, including fever (83.3%) and respiratory distress (66.7%). Three neonates had thrombocytopenia, with a median minimum platelet count of 69,500/mm 3 (IQR 38,000-81,500/mm 3 ). One newborn with severe dengue experienced plasma leakage. All newborns progressed favorably with symptomatic and supportive care after a median hospitalization of 9 days (IQR 8-12 days).

DENV infection should be considered in the differential diagnosis for nonspecific acute febrile syndrome in pregnant women and neonates during dengue outbreaks to provide adequate clinical management of both mothers and infants.