Objective: To report an outbreak of ZIKV infection among asymptomatic pregnant women during 2016 in the city of Jaen, Cajamarca. Results: Zika virus RNA was detected in 3.2% (n = 36) of cases by RT-PCR. The mean age of patients positive for ZIKV infection was 29.6 years. 7 patients (19.4%) infected with ZIKV were in their first-trimester of gestation, 13 (36.1%) were in their second-trimester, and 16 (44%) were in their third-trimester. All of the infected pregnant women were asymptomatic. ZIKV infection remains a major public health issue that calls for constant epidemiological surveillance. It can cause the congenital Zika virus syndrome in the newborns of infected mothers. The lack of molecular diagnostic methods in isolated localities and the similarity of symptoms to other arboviral infections, lead to an under-diagnosis of this disease in endemic areas. © 2018 The Author(s).