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EW NEWS & OPINION 18 November 2016 by Camila Ventura, MD affected are the retina, optic nerve, and vasculature. 1,2,8,15,16 The retinal findings include chorioretinal scars and gross pigmentation, generally affecting the macular region. Optic nerve hypoplasia is the most com- mon optic nerve finding, however optic nerve pallor and increased disc cupping can also be identified. 2,8,15 Furthermore, Miranda et al. recently expanded the ocular spectrum by describing retinal hemorrhages and peripheral vasculature abnormali- ties. 16 We also are now aware of the main risk factors associated with the ocular findings in CZS. The risk factors include the severity of micro- cephaly at birth and the trimester when the infection occurred—the first trimester being directly related to ocular findings as well as severe microcephaly. 8 An important scientific para- digm shift occurred when we report- ed the first case of a patient with CZS who did not present microceph- aly. 17 In the beginning, scientists thought that all babies affected by Zika virus intra-uterus would necessarily present microcephaly at birth. For months, microcephaly was a required criterion for further investigations in these babies, in- cluding serological and clinical eval- uations. 1,2,8,13–15 However, after we reported a baby with normal head circumference at birth with other systemic findings such as ocular and neurological abnormalities, and van der Linden et al. subsequently reported another patient with nor- mal head circumference at birth and arthrogryposis, this criterion became obsolete. 10,17 The current Centers for Disease Control (CDC) guidelines recom- mend that initial clinical evalua- tion should be done in all infants with laboratory evidence of Zika virus infection with or without abnormalities consistent with CZS, as well as babies with abnormal clinical or neuroimaging findings at birth. 18 The initial ocular screening should be performed before hospital discharge or within 1 month and should include fundus evaluation. It is also recommended to repeat the may cause a variety of systemic ab- normalities. 12 Due to the avalanche of novel information regarding ZIKV and congenital abnormalities, scientists now consider ZIKV a new congenital infection. This new enti- ty comprehends a broad spectrum of signs and symptoms with different levels of severity called congenital Zika syndrome (CZS). 13 The main abnormalities re- ported so far include neurological, ocular, hearing, and skeletal find- ings. 8–11 According to de Fatima Vasco Aragao et al., 14 the main neurological findings identified in infants with CZS are decreased brain volume, cerebral calcifications (sub- cortical and periventricular), ven- triculomegaly, delayed myelination, and corpus callosum and cerebellar abnormalities. Regarding the ocular findings in CZS, the principal structures and other neurological findings us- ing animal models, and these studies have shown that ZIKV attacks cortical progenitor cells in the brain impairing neurodevelopment. 4–6 The second important accom- plishment was the development of specific serological testing for ZIKV. 7 Here I should mention that the current serology test is not ideal due to its high cross-reactivity with other Flavivirus, and it is still not easily accessed in many countries with active transmission of the disease. 7,8 Nevertheless, the current serology gave us enough support to be able to confirm ZIKV infection in previously infected babies and to relate all sys- temic findings, including the ocular findings, to the vertical transmission of ZIKV. 8–11 We currently know that the transmission of ZIKV to fetuses occurs through the placenta and An update on what is known so far about this infection N ot long ago, my colleagues and I reported the first ocular findings identified in babies with a presumed diagnosis of congenital Zika infection. 1,2 At the time, there was no proof that Zika virus (ZIKV) was responsible for the microceph- aly observed in affected babies, nor did we know that it could cause the ocular findings that we were report- ing. Since then, numerous discov- eries have led us toward a better understanding of this new disease. The first big scientific achieve- ment was to prove the relationship of ZIKV and microcephaly. 3 Sci- entists have been addressing the pathophysiology of microcephaly Congenital Zika syndrome Typical retinal lesion seen in congenital Zika syndrome: chorioretinal scar affecting the macular region Source: Altino Ventura Foundation collection

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