Braga José Ueleres, Bressan Clarisse, Dalvi Ana Paula Razal, Calvet Guilherme Amaral, Daumas Regina Paiva, Rodrigues Nadia, Wakimoto Mayumi, Nogueira Rita Maria Ribeiro, Nielsen-Saines Karin, Brito Carlos, Bispo de Filippis Ana Maria, Brasil Patrícia
Escola Nacional de Saude Publica, Fundacao Oswaldo Cruz, Rio de Janeiro, Brazil.
Instituto de Medicina Social, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil.
PLoS One. 2017 Jun 26;12(6):e0179725. doi: 10.1371/journal.pone.0179725. eCollection 2017.
Zika is a new disease in the American continent and its surveillance is of utmost importance, especially because of its ability to cause neurological manifestations as Guillain-Barré syndrome and serious congenital malformations through vertical transmission. The detection of suspected cases by the surveillance system depends on the case definition adopted. As the laboratory diagnosis of Zika infection still relies on the use of expensive and complex molecular techniques with low sensitivity due to a narrow window of detection, most suspected cases are not confirmed by laboratory tests, mainly reserved for pregnant women and newborns. In this context, an accurate definition of a suspected Zika case is crucial in order for the surveillance system to gauge the magnitude of an epidemic.
We evaluated the accuracy of various Zika case definitions in a scenario where Dengue and Chikungunya viruses co-circulate. Signs and symptoms that best discriminated PCR confirmed Zika from other laboratory confirmed febrile or exanthematic diseases were identified to propose and test predictive models for Zika infection based on these clinical features.
Our derived score prediction model had the best performance because it demonstrated the highest sensitivity and specificity, 86·6% and 78·3%, respectively. This Zika case definition also had the highest values for auROC (0·903) and R2 (0·417), and the lowest Brier score 0·096.
In areas where multiple arboviruses circulate, the presence of rash with pruritus or conjunctival hyperemia, without any other general clinical manifestations such as fever, petechia or anorexia is the best Zika case definition.
寨卡病毒病是美洲大陆的一种新疾病，对其监测至关重要，尤其是因为它能够通过垂直传播导致吉兰 - 巴雷综合征等神经表现以及严重的先天性畸形。监测系统对疑似病例的检测取决于所采用的病例定义。由于寨卡病毒感染的实验室诊断仍依赖于使用昂贵且复杂、检测窗口期窄导致灵敏度低的分子技术，大多数疑似病例无法通过实验室检测确诊，实验室检测主要针对孕妇和新生儿。在此背景下，准确界定寨卡疑似病例对于监测系统评估疫情规模至关重要。
我们在登革热病毒和基孔肯雅病毒共同流行的情况下，评估了各种寨卡病例定义的准确性。识别出能将聚合酶链反应（PCR）确诊的寨卡病毒感染与其他实验室确诊的发热或出疹性疾病最佳区分开来的体征和症状，以基于这些临床特征提出并测试寨卡病毒感染的预测模型。
我们推导的评分预测模型表现最佳，因为它分别具有最高的灵敏度和特异性，即86.6%和78.3%。这个寨卡病例定义在曲线下面积（auROC）（0.903）和决定系数（R2）（0.417）方面也具有最高值，且布里尔评分（Brier score）最低，为0.096。
在多种虫媒病毒流行的地区，出现伴有瘙痒的皮疹或结膜充血，且无发热、瘀点或厌食症等任何其他一般临床表现，是最佳的寨卡病例定义。
