03437nas a2200409   4500000000100000008004100001653001500042653001900057653001700076653001100093653001700104653002600121100001300147700001300160700001600173700001500189700002700204700001200231700002800243700002500271700001100296700002100307700001300328700001200341700002300353700001200376700002800388700001500416700001500431700002400446700001500470245011900485856009000604300000900694490000700703520231700710       2016                            d10aZika virus10aRio de Janeiro10aMicrocephaly10aFevers10aEpidemiology10aChikungunya infection1 aBrasil P1 aCalvet G1 aSiqueira AM1 aWakimoto M1 aCarvalho de Sequeira P1 aNobre A1 aSouza Borges Quintana M1 aLima de Mendonça MC1 aLupi O1 aValls de Souza R1 aRomero C1 aZogbi H1 aSilveira Bressan C1 aAlves S1 aLourenço-de-Oliveira R1 aNogueira R1 aCarvalho M1 aBispo de Filippis A1 aJaenisch T00aZika virus outbreak in Rio de Janeiro, Brazil: Clinical characterization, epidemiological and virological aspects.  uhttp://journals.plos.org/plosntds/article/asset?id=10.1371%2Fjournal.pntd.0004636.PDF  a1-130 v103 a<p><strong>Background. </strong>In 2015, Brazil was faced with the cocirculation of three arboviruses of major public health importance. The emergence of Zika virus (ZIKV) presents new challenges to both clinicians and public health authorities. Overlapping clinical features between diseases caused by ZIKV, Dengue (DENV) and Chikungunya (CHIKV) and the lack of validated serological assays for ZIKV make accurate diagnosis difficult.</p>

<p><strong>Methodology / Principal Findings</strong>. The outpatient service for acute febrile illnesses in Fiocruz initiated a syndromic clinical observational study in 2007 to capture unusual presentations of DENV infections. In January 2015, an increase of cases with exanthematic disease was observed. Trained physicians evaluated the patients using a detailed case report form that included clinical assessment and laboratory investigations. The laboratory diagnostic algorithm included assays for detection of ZIKV, CHIKV and DENV. 364 suspected cases of Zika virus disease were identified based on clinical criteria between January and July 2015. Of these, 262 (71.9%) were tested and 119 (45.4%) were confirmed by the detection of ZIKV RNA. All of the samples with sequence information available clustered within the Asian genotype.</p>

<p><strong>Conclusions / Significance.</strong> This is the first report of a ZIKV outbreak in the state of Rio de Janeiro, based on a large number of suspected (n = 364) and laboratory confirmed cases (n = 119). We were able to demonstrate that ZIKV was circulating in Rio de Janeiro as early as January 2015. The peak of the outbreak was documented in May/June 2015. More than half of the patients reported headache, arthralgia, myalgia, non-purulent conjunctivitis, and lower back pain, consistent with the case definition of suspected ZIKV disease issued by the Pan American Health Organization (PAHO). However, fever, when present, was low-intensity and short-termed. In our opinion, pruritus, the second most common clinical sign presented by the confirmed cases, should be added to the PAHO case definition, while fever could be given less emphasis. The emergence of ZIKV as a new pathogen for Brazil in 2015 underscores the need for clinical vigilance and strong epidemiological and laboratory surveillance.</p>