[Zika virus embryopathy in Argentina: clinical characteristics in newborns]. / Embriopatía por virus Zika en Argentina: características clínicas y diagnóstico en recién nacidos.

Introduction: Microcephaly and brain abnormalities may be due to multiple etiologies, one of them is the congenital infection by Zika virus (ZIKV). From 2016 to the present, there has been a series of ZIKV outbreaks in Argentina. Methods: National Network of Congenital Anomalies (RENAC) and the National Institute of Viral Diseases (INEVH), under the National Administration of Laboratories and Health Institutes "Carlos Malbrán" (ANLIS), carry out the intensified surveillance of newborns with microcephaly and brain abnormalities. This article presents the clinical characteristics and laboratory testof patients detected with congenital infection by ZIKV between April 2016 to March 2018, Results: 10 cases with embryopathy were detected, six autochthonous and four imported; in two cases, the mothers were asymptomatic during pregnancy; all the cases presented microcephaly and cranial facial disproportion, ventriculomegaly in seven cases and in six cerebral calcifications. The diagnosis of congenital infection by Zika in the newborn was made by antigen-specific Immunoglobulin M (MAC-ELISA) and plaque-reduction neutralization test (PRNT90 ). PCR was negative in all cases. Conclusion: the patients presented clinical features that were consistent with those reported in other countries. The need for serological studies that allow confirmation is emphasized, ruling out cross-reactivity with other Flaviviruses.

Introducción: La microcefalia y las anomalías cerebrales congénitas pueden deberse a múltiples etiologías, siendo uno de ellas la infección congénita por el virus Zika (ZIKV). Desde 2016 hasta hoy se han sucedido una serie de brotes del ZIKV en Argentina. Métodos: La Red Nacional de Anomalías Congénitas (RENAC) y el Instituto Nacional de Enfermedades Virales (INEVH), dependientes de la Administración Nacional de Laboratorios e Institutos de Salud "Carlos Malbrán" (ANLIS), realizan la vigilancia intensificada de recién nacidos con microcefalia y anomalías cerebrales. Este trabajo presenta las características clínicas y estudios de laboratorio de los pacientes con infección congénita por ZIKV detectados entre abril de 2016 a marzo 2018. Resultados: se detectaron 10 casos con embriopatía, seis fueron autóctonos y cuatro importados; en dos casos las madres fueron asintomática durante el embarazo; todos los casos presentaron microcefalia y desproporción cráneo facial, ventriculomegalia en siete casos y en seis calcificaciones cerebrales. El diagnóstico de infección congénita por Zika en el recién nacido se realizó por estudios serológicos inmunoglobulina M antígeno específica (MAC-ELISA) y prueba de neutralización por reducción de placas (PRNT90). La PCR fue negativa en todos los casos. Conclusión: Los pacientes presentaron características clínicas coincidentes con las reportadas en otros países Se enfatiza la necesidad de estudios serológicos que permitan la confirmación, descartando la reactividad cruzada con otros Flavivirus.

Surveillance of microcephaly and selected brain anomalies in Argentina: Relationship with Zika virus and other congenital infections.

BACKGROUND: Zika virus (ZIKV) vertical transmission may lead to microcephaly and other congenital anomalies. In March and April 2016, the first outbreak of ZIKV occurred in Argentina. The objective was to describe the surveillance of newborns with microcephaly and other selected brain anomalies in Argentina, and evaluation different etiologies. METHODS: Participants were enrolled between April 2016 and March 2017. CASES: newborns from the National Network of Congenital Abnormalities of Argentina (RENAC) with head circumference lower than the 3rd percentile according to gestational age and sex, or selected brain anomalies. Blood and urine samples from cases and their mothers were tested for ZIKV by real-time polymerase chain reaction (RT-PCR), antigen-specific Immunoglobulin M (MAC-ELISA) and plaque-reduction neutralization test (PRNT90 ). Toxoplasmosis, rubella, herpes simplex, syphilis, and cytomegalovirus (CMV) infection were also tested. RESULTS: A total of 104 cases were reported, with a prevalence of 6.9 per 10,000 [95% confidence interval (CI): 5.7-8.4], a significant increase when compared with the data prior to 2016, Prevalence Rate Ratio 1.7 (95% CI 1.2-2.3). In five cases positive serology for ZIKV (IgM and IgG by PRNT) was detected. The five cases presented microcephaly with craniofacial disproportion. We detected four cases of CMV infection, three cases of congenital toxoplasmosis, two cases of herpes simplex infection, and one case of congenital syphilis. CONCLUSION: The prevalence of microcephaly was significantly higher when compared with the previous period. The system had the capacity to detect five cases with congenital ZIKV syndrome in a country with limited viral circulation.