Zika virus infection during pregnancy and microcephaly occurrence: a review of literature and Brazilian data

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w w w . e l s e v ie r . c o m / l o c a t e / b j i d

The

Brazilian

Journal

of

INFECTIOUS

DISEASES

Review

article

Zika

virus

infection

during

pregnancy

and

microcephaly

occurrence:

a

review

of

literature

and

Brazilian

data

Newton

Sérgio

De

Carvalho

a,∗

_,

_Beatriz

_Freitas

_De

_Carvalho

b

_,

_Cyllian

_Arias

_Fugac¸a

b

_,

Bruna

Dóris

b

_,

_Evellyn

_Silverio

_Biscaia

b

a_Department_of_Gynecology_and_Obstetrics,_Universidade_Federal_do_Paraná_(UFPR),_Infectious_Diseases_in_Gynecology_and_Obstetrics

Sector,ClinicsHospitalandPostgraduateEducationPrograminObstetricsandUniversidadeFederaldoParaná(UFPR),Curitiba, PR,Brazil

b_Pontifícia_Universidade_Católica_do_Paraná_(PUC-PR),_Curitiba,_PR,_Brazil

a

r

t

i

c

l

e

i

n

f

o

Articlehistory:

Received29December2015 Accepted23February2016 Availableonline18April2016

Keywords: Zikavirus Microcephaly Aedesmosquitoes Pregnancy

a

b

s

t

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a

c

t

InNovemberof2015,theMinistryofHealthofBrazilpublishedanannouncementconfirming therelationshipbetweenZikavirusandthemicrocephalyoutbreakintheNortheast, sug-gestingthatinfectedpregnantwomenmighthavetransmittedthevirustotheirfetuses. TheobjectivesofthisstudyweretoconductaliteraturereviewaboutZikavirusinfection andmicrocephaly,evaluatenationalandinternationalepidemiologicaldata,aswellasthe currentrecommendationsforthehealthteams.Zikavirusisanarbovirus,whosemain vectoristheAedessp.Themainsymptomsoftheinfectionaremaculopapularrash,fever, non-purulentconjunctivitis,andarthralgia.Transmissionofthispathogenoccursmainly bymosquitobite,buttherearealsoreportsviatheplacenta.Microcephalyisdefinedasa measureofoccipto-frontalcircumferencebeingmorethantwostandarddeviationsbelow themeanforageandgender.Thepresenceofmicrocephalydemandsevaluationofthe patient,inordertodiagnosetheetiology.Healthauthoritiesissuedprotocols,reportsand notesconcerningthemanagementofmicrocephalycausedbyZikavirus,butthereisstill controversyaboutmanagingthecases.TheMinistryofHealthadvisesnotifyingany sus-pectedorconfirmedcasesofchildrenwithmicrocephalyrelatedtothepathogen,whichis confirmedbyapositivespecificlaboratorytestforthevirus.Thefirstchoiceforimaging examinchildrenwiththismalformationistransfontanellarultrasound.Themosteffective waytocontrolthisoutbreakofmicrocephalyprobablycausedbythisvirusistocombatthe vector.Sincethereisstilluncertaintyabouttheperiodofvulnerabilityoftransmissionvia placenta,theuseofrepellentsiscrucialthroughoutpregnancy.Moreinvestigationsstudying theconsequencesofthisviralinfectiononthebodyofnewbornsandintheirdevelopment arerequired.

∗ _{Corresponding}_author.

E-mailaddress:newtonsdc@gmail.com(N.S.DeCarvalho). http://dx.doi.org/10.1016/j.bjid.2016.02.006

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Introduction

InNovemberof2015,theMinistryofHealth(MOH)ofBrazil issuedabulletin conﬁrming the relationshipbetween Zika virus(ZIKV)infectionandthemicrocephalyoutbreakinthe northeasternregion.1

One of the first records of ZIKV disease in the coun-try isfrom Marchof2015,inthe stateofBahia, Northeast Brazil,inwhichpatientswith“dengue-likesyndrome”showed positivityinblood analysisby molecularbiology (realtime PCR-RT-PCR).2_{Autochthonous}_transmission_by_ZIKV_was con-firmedinBrazilinApril20153_and_in_May_of_the_same_year,_the BrazilianMOHconfirmedthecirculationofthevirus.4

From an obstetric perspective, in October of2015 there wasan unusualincrease inthe number ofnewborns with microcephalyinthestateofPernambuco(Northeast). Consid-eringthatsomeofthemothers ofthesebabieshad arash duringpregnancy5_the_possibility_of_ZIKV_transmission_from mothertochild,causingneurologicaldefectsinthechild,was suggested.Afterconductingtestsinababybornwith micro-cephalyandothermalformationsinoneoftheNortheastern states,thepresenceofthevirusinbloodandtissuesofthe patientwasdetected,provingthatassumption.4

Currently, due to the progressive extension of cases of microcephaly,correspondingto4783suspectedand404 con-ﬁrmedcases,6_this_situation_became_extremely_concerning_to publichealth,sinceonly18%oftheinfectedaresymptomatic4 andthereisnotreatmentforthiscondition.7_Therefore,_the controlofpregnantwomenwhomightbearachildwith micro-cephalyis impaired, and consequently, astrict monitoring duringprenatalcareisneeded.

Inviewofthisnewandalarmingscenery,thisstudyaimed toconductaliteraturereviewaboutZIKVandmicrocephaly, evaluateepidemiologicaldata publisheduntil February 5th 2016innationalandinternationallevels,aswellastoreview thecurrentrecommendationsforthehealthteams.

Zika

virus

The ZIKV is an arbovirus (arthropod-born virus), since part of its reproductive cycle occurs within the body of hematophagousinsets.TheybelongtotheFlaviviridae fam-ily,andFlavivirusgenus,whosemembersarecomposedbya proteincapsidinvolvedbyalipidenvelope,inwhichthe mem-braneproteinandglycoproteinspikesareinserted.TheAedes sp.mosquitoes are thevectors responsiblefortransmitting thismicroorganism, aswell asChikungunyavirus (CHIKV), denguevirus(DENV),yellowfevervirus(YFV),andWestNile fevervirus(WNV).8

TheZIKVwasinitiallyisolatedinaRhesusmonkey,atthe AfricanZikaforestinUganda.Inthe60s,thefirstcasesofZIKV infectioninhumans havebeen confirmedbyserologic evi-denceinthecountriesofUganda,Nigeria,andSenegal.9_The disseminationwassogreatthatin2007thefirstoutbreak out-sideAfricaandAsiawasreported,ontheYapIsland(Federated StatesofMicronesia).InOctoberof2013,thelargestZIKV out-breakaffectedapproximately28,000inhabitantsoftheFrench Polynesia.8 _After_two_years,_in_May₂₀₁₅_the_Brazilian_MOH issuedastatementconfirmingthefirstcasesidentifiedinthe

country:16peopleintheNortheast,atBahiaandRioGrande doNortestates,weretestedpositiveforthevirus.4

The condition of ZIKV infection is named “dengue-like syndrome”becauseitresemblesaninfection causedbythe DENV.9 _The_clinical _criteria_for _diagnosing_this _self-limited disease are pruritic maculopapular rash plus at least two ofthefollowing:fever(generallylowgradefeverlasting1–2 days),non-purulentconjunctivitis,polyarthralgia,and periar-ticularswelling.10_Other_signs_and_symptoms_may_be_present, suchasmusclepain,retroocularpain,vomiting,andlymph node hypertrophy.9 _Besides, _ZIKV _infection _can _affect _the centralnervoussystem(CNS).Therearereportsofa20-fold increaseintheincidenceofGuillain–BarreSyndrome(GBS)in MicronesiaduringtheoutbreakofZIKV,inadditiontocases ofGBSafterinfectionbythispathogeninFrenchPolynesia.11 However, about 80% ofinfections are asymptomatic, what makesthediagnosisandpreventionoftransmissionhighly challenging.12

ThedetectionofviralRNAintheacutephase–upto10days fromonsetofsymptoms–byRT-PCRassayisthemethodof choiceforidentiﬁcationofthevirussofar.Fortunately, stud-iestoimprovetheidentiﬁcationofimmunoglobulin(IgM)by ELISAarebeingcarriedout,butcross-reactionwiththeDENV islikelytooccurinendemicareasofdenguefever.5,13 More-over,anotherstudysuggestedthepossibilityofdiagnosingthe infection from urine samples. ViralRNA wasisolated even after10daysofonsetofsymptoms,whichshowsthat this techniqueissuitableforlaterdiagnosiswhencomparedwith testsusingbloodsamples.14

Transmission

ZIKVismainlytransmittedbytheAedesaegyptivector,which residesintropicalandsubtropicalregions,aswellasbythe Aedes albopictus,inhabitantoftheEuropeanMediterranean. After the mosquito’s bite, there isan incubation periodof aboutninedays,andthenthesymptomsensue.15,16

Althoughthereisnoevidenceofsexualtransmissionin humans by other arboviruses, some authors hypothesized that this could be possible for ZIKV. Patients exposed to endemicareasshowedsymptomsofthediseaseandone atyp-icalsignalofhematospermia.Insuchcases,thepresenceof virusinsemenwasconﬁrmedbyserologicaltestsorby RT-PCR.Inaddition,oneofthesexualpartnersofthesepatients hadsimilarsymptoms,strengtheningthisassumption.8,16

DuringtheoutbreakinFrenchPolynesia,astudyto inves-tigate ZIKVin blood donorswas carried out using RT-PCR modiﬁed technique. It was noted that 3% of donors were asymptomatichostsofthevirus,butnocaseofinfectionwas identiﬁedafterbloodtransfusion.Still,theresultssuggestthat testingforZIKVmustbeimplementedintheroutineofblood donation.15,17

Regardingperinataltransmission,whichisthemainfocus of this review article, on November 17th 2015 investiga-torsoftheOswaldoCruzInstitute(OCI/Fiocruz)detectedthe presenceofZIKVgenome inamniotic fluidsamplesoftwo pregnantwomeninthestateofParaiba(Northeast),inwhom ultrasound exams had confirmed microcephalic fetuses.18 Thisfacttakeninisolationdoesnotconfirmtransplacental

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transmissionofthevirusbutishighlysuggestive,sincemost ofthepathogensthatcauseinfectionsinpregnancy,suchas toxoplasmosis,canbedetectedintheamnioticﬂuid.19

At the same time, the French Polynesian authorities reportedasigniﬁcantincreaseincasesofCNSmalformations infetusesbornbetween2014and2015,whichwastheperiod ofZIKVoutbreakintheregion.20_In_this_nation,_a_study20 sug-geststhatotherformsofcontagion,suchasmilkandsaliva, oughttobeconsidered.Thiswasevidencedincasesinwhich RT-PCRwaspositiveforZIKVinmother’smilk,andbaby’sand mother’ssaliva,butwheninoculatedinVerocellstheviruses didnot replicate.However,since this kindof transmission canoccurinotherarboviraldiseases,likedengue21_and_West Nilefever,22_these_{possibilities}_of_{contamination}_should_not beneglected.

Oneoftheconcernsabouttheinfectioninwomenisthe viruslatencyperiod,becauseitisnotknownifavirusacquired in a non-pregnant woman could have a potential impact onafuturefetus.Thatiswhysomeprotocolshighlightthe importanceofalsonotifyingcasesinwhichwomenhave expe-riencedsymptoms40daysbeforepregnancy.23

Microcephaly

Microcephaly is defined as the measurement of head occipto-frontalcircumferencebeingmorethantwostandard deviationsbelowthemeanforageandgender.24_It_is_known that the brain of microcephalic patients is proportionally smaller,thusabout90%ofthecasesareassociatedwithsome degreeofintellectualdisability.5_It_is_important_to_remind_that microcephalyisnotadiagnosisbutaclinicalfinding,therefore furtherinvestigationisnecessarywhenfacingthissituation.25 Regardingtheinitiation,microcephalycanbeclassifiedas primary(congenital)orsecondary(postnatal).Primary micro-cephalycan bedetectedbefore36 weeksofgestation.This mayoccurbyfailureorreductionofneurogenesis,by destruc-tivepre-natalinsultsorbyveryearlydegenerativeprocesses.25 Thesecondarymicrocephalyiscausedbyanyinsultfactorin thedevelopmentandfunctionoftheCNS.Itassociates com-monlywithneurologicaldisorders.25

Theetiologicalapproachofmicrocephalyisextensive,as this can be caused by many genetic, environmental, and maternal factors.5 _Not _{infrequently,} _genetic _microcephaly progresseswithdysmorphicfeaturesorconcomitantlywith other congenital abnormalities and it is very common the association with syndromes, as in Down Syndrome.5,25,26 As for environmental and maternal factors, there are hypoxic ischemic insults, placental insufﬁciency, systemic andmetabolicdisorders,exposuretoteratogensduring preg-nancy,pregnantwomenwithseveremalnutrition,maternal phenylketonuria, andCNS infections (suchas rubella, con-genitaltoxoplasmosis,cytomegalovirusinfection,herpes,and HIV).5,25_However,_in_some_cases,_the_etiology_of_microcephaly cannotbedeﬁned(idiopathic).25

Concomitantlywiththeincreaseincasesofmicrocephaly notiﬁed byMOH,therewas an outbreakofZIKV infection, whichwaslistedasapossiblecauseofthatmalformation.20 AccordingtoinformationreportedbytheBrazilianlivebirths information system (SINASC), the extension of the 2015

Nove mber 15th to 21th Nove mber 22th to 28th No vember 29th to December 5th

December 6th to 12th_{December 13th to 19th}_{December 20th to 26th}

December 27th to J anuar y 2nd Janu ary 3rd to 9th Janu ary 10th to 16th Janu ary 17th to 23th Janu ary 24th to 30th 739 1248 1761 2401 2782 2975 3174 3530 3893 4180 4783

Fig.1–Suspectedcasesofmicrocephaly.Graphshowing theprogressiveprevalenceofsuspectedcasesof

microcephalyoccurringinBrazilfromthebeginningofthe ZikavirusoutbreakuntilJanuary30,2016.6,29–38

situationbecomesevenmoresignificantcomparedtoprevious years.From2010to2014therewerearound150casesreported peryearinthecountry,andcurrently,suspectedcasestotaled 4783.6,27 _Six _months _have _elapsed _between _the _first _virus transmissionreports(May2015)andmicrocephalyoutbreak (November2015),whichistheappropriatedtimefor diagnos-ingcranialabnormalitiesbyprenatalultrasoundexamination, suggestingatemporal correlation. Theincrease incasesof microcephalyoccurredinthesameareawheretherehadbeen circulationofvirus,indicatingalsoaplacecorrespondence.27 Asaresultofthe increasingimpactofthis scenery, the MOH deployedtheEmergencyOperations CenteronHealth Issues (COES) on November 10th 2015, and after one day, declared“PublicHealthEmergencyofNationalImportance”.28 TheCOESweeklypublishesepidemiologicalreports,making itpossibletocompareandobservealargegrowthinthe num-berofsuspectedcasesofmicrocephaly(Fig.1),andalsothe progressiveinvolvementofotherBrazilianstatesindifferent regionalareas(Figs.2and3).Ofthetotalofsuspectedcases, 3670areunderinvestigation,404havebeenconfirmed,and 704werediscardedfromsurveillance.6

Nove mber 15th to 21th Nove mber 22th to 28th Nove mber 29th to December 5th

December 27th to J anuar y 2nd Janu ary 3rd to 9th Janu ary 10th to 16th Janu ary 17th to 23th Janu ary 24th to 30th 9 14 14 20 20 20 21 21 27 27 27

Fig.2–Affectedfederalunits.Graphshowingthe

progressiveprevalenceofsuspectedcasesofmicrocephaly accordingtothenumberofBrazilianstates,orFederal units,affectedfromthebeginningoftheZikavirus outbreakuntilJanuary30,2016.6,29–38

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0 Nove mber 15th to 21th Nove mber 22th to 28th No vember 29th to December 5th

December 27th to J anuar y 2nd Janu ary 3rd to 9th Janu ary 10th to 16th Janu ary 17th to 23th Janu ary 24th to 30th 7 19 27 40 ₃₇ ₃₈ 46 49 68 76

Fig.3–Suspecteddeaths.Graphexhibitingtheprogressive prevalenceofsuspecteddeathsrelatedwithmicrocephaly causedbytheZIKVoccurringinBrazilfromthebeginning oftheoutbreakuntilJanuary30,2016.6,29–38

Scientiﬁc evidence support the relation between ZIKV infection and microcephaly. The literature describes neu-rotropism as a characteristic of ZIKV in laboratory tests involvingrats.39_This_fact_endorses_the _hypothesis_that_the virus directlyacts onnerve cellsofthe fetus.Yet, another possibilityisthatthemechanismoccursthroughtheimmune system,suchasinGuillain–Barrecondition,whereantibodies areformedagainstneuronalmyelinsheath.40

Differentarboviruseshavealsoshown neurological con-sequences in perinatal infections, suchas encephalopathy byCHIKVinhumans41_and_necrotizing_{encephalopathy}_and whitemattervacuolizationbytheAkabanevirusinsheepand goats.42_In_addition,_arboviruses_can_cause_meningitis, myeli-tis,neuritis,producing symptoms suchasheadache, fever, vomiting,peripheralneuropathy,seizures,andeven Parkin-sonismandchronicepilepsy.43

Otherfacts alsocorroboratethis association.In Novem-ber2015,theEvandroChagasInstitutedeclaredthepresence ofZIKVgenomeinbloodandtissuesofababywith micro-cephaly,whodied5minafterbirth.1,20_Likewise,_according_to theepidemiologicalreportsofCOES, thenumber ofdeaths assumedtobeassociatedwiththisdeformityhasexpanded signiﬁcantlysincethiscase.Amongthe76suspectedcases,15 wereconﬁrmed.6

Furthermore,analysisofmedicalrecords andinterviews with60women,whopresentedarashduringtheirpregnancy andwhosebabieswerebornwithmicrocephaly,showedan absenceofothergeneticdisordersinthefamilyandofﬁndings thatmightsuggestothersinfections.Thus,the exanthema-tousdiseaseisprobablytheputativecauseofthisdeformity.44 Inspiteofthe relationbetweenmicrocephalyand ZIKV infectionbeingestablishedinBrazil,someepidemiccountries, suchasMicronesiaandNewCalendonia,showednoraisein thenumberofcongenitalCNSdeformities.Itisworth remem-bering that, however, such sites haveconsiderably smaller population as well as less registered cases, making their limitedsampledifﬁculttoanalyze.27

Themicrocephalyisananomalyinwhichtheskullgrowth islimitedduetothelackofstimulationasaresultofthedeﬁcit inthebraingrowth.45_The_ﬁrst_trimester_of_pregnancy_is_when

thereisgreatestriskthatsomeexternalfactorwouldcause malformations in the developingchild. Butwhen it comes totheCNS,theriskexiststhroughoutpregnancy.5_According toanalysescarriedoutinBrazil,theriskofmicrocephalyor congenitalabnormalitiesinnewbornsassociatedwithZIKV isgreaterwhentheinfectionoccursintheﬁrsttrimesterof pregnancy.20,27 _Health _authorities _of_French _Polynesia sug-gestedthatthecriticalinterval wouldbeduringtheﬁrstor secondtrimesters.20,27_{Nevertheless,}_the_gestational_period_of majorvulnerabilityremainsunknown.

Moreover,ithasbeensuggestedthatmicrocephalyrelated toZIKVcouldbemoreaggressive.Accordingtoaresearchwith a cohortof35 babiesthat were bornwithmicrocephalyin Brazilianaffected areas,71%ofthem hadthis abnormality in asevere level.46 _{Consequently,} _depending _on _the inten-sity,itcouldleadtoseizures,hearingandvisionimpairment, intellectualdisability,developmentalimpairment,andevena life-threateningcondition.47

Detecting,

monitoring

and

managing

WhereasZIKVinfection becameapublichealthemergency, theBrazilianMOHandseveralstatehealthdepartmentshave publishedprotocols,reportsandnotesconcerningthe diag-nosisandmanagementofcongenitalmicrocephaly.Asitisa recentcondition,thereisstillmuchcontroversyabout guide-lines and dynamic ﬂowcharts. For this part of the review, weselectedtechnicalreportsofStateDepartmentsofHealth (SESA)oftwostatesconsideredofgreatimportanceinthis epi-demiologicalsituation:SãoPauloandPernambuco,inaddition totheMOHprotocols.

TheMOHpublishedthe“SurveillanceProtocolinResponse totheOccurrenceofMicrocephalyrelatedtotheZIKV Infec-tion”.Thisdocumentadvisesthatthepresenceofexanthema inapregnantwoman,regardlessofgestationalage,features asuspectedcaseofZikavirusinfection,afterrulingoutother infectious and non-infectious causes. The confirmation is madebyaspecificpositivelaboratorytestforthepathogen. TheMOH recommendstwo bloodsamplesofthe pregnant woman underinvestigation:the firstcollected threetofive daysaftertheonsetofsymptomsandthesecondtwotofour weeksafterthefirstsample.Thematerialwillonlybe ana-lyzedbyPCRiftheserologyispositive.TheZIKV-specificIgM antibodiescanbedetectedbyELISAorimmunofluorescence assaysinserumspecimensfromdayfiveaftertheonsetof symptoms.However,therearenocommercialkitsfor sero-logicaldiagnosisofZIKV.44,48

Themanagement ofpregnant womenwithsuspicionof ZIKVinfectiondiffersslightlybetweentheSESAof Pernam-buco, theSESA ofSaoPaulo,and recommendations bythe MOH.AccordingtotheSESAofPernambuco,itisnecessaryto collectabloodsamplewithinﬁvedaysoftheonsetof symp-tomsandaurinesamplewithineightdays,thenrepeatblood sampling 14–21 days after the start of clinical symptoms. These sampleswillbeanalyzedbyserologyand molecular biology forZIKV.Still,forthis groupofpregnantwomen it is recommended an ultrasound examination between the 32 and 35 weeks ofgestation regardlessof laboratory test results.5 _For _the _São _Paulo _SESA, _the _only_difference _from

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theMOHrecommendationsisthatthesecondblooddrawing shouldbedone3–4weeksaftertheonsetofsymptoms.49

Forthepregnantwomenwithnohistoryofskinrashand whogavebirthtoachildwithmicrocephaly,theMOH recom-mends collecting a mother’s blood sample at the time of diagnosisofthechild’smalformation,andasecondblood col-lection2–4weeksaftertheﬁrstsample.44_The_report_of_São PauloStatedeterminesthatthesecondtestshouldbedone3–4 weeksaftertheﬁrstcollection,49_while_{Pernambuco’s}_Protocol doesnotspecifyaboutthislay-off.5

Thediagnosis of microcephalycan bemade duringthe prenatal and/or postnatal periods. According to the MOH recommendations acase shoulddeemed suspected during pregnancywhenthefetuspresentsheadcircumference(HC) withtwostandarddeviationsbelowthemeanforgestational ageorwhenthereisanultrasoundfinding withCNS alter-ationsuggestiveofcongenitalinfection.Anysuspectedcase ofmicrocephalycausedbyZIKVshouldbeimmediately noti-fiedtohealthauthorities.Inordertoconfirm,itisnecessary toruleoutotherinfectiousandnon-infectiouscausesor per-formlaboratorytests.44 _The_{Pernambuco’s}_Protocol_propose that, ifthere ispositivityinthesetests, the health profes-sionalmustissueanotificationtothelocalhealthauthorities, explaintheultrasoundfindingstothemother,evaluatethe needforrepeatingtheultrasound,keepprenatalcareroutine –asisolatedmicrocephalydoesnotcharacterizepregnancy ashighrisk–andguidethepregnantwomantopsychosocial supportbyamultidisciplinaryteamofthehealthunit.5The SãoPauloSESAdoesnotspecifythecorrectapproachtoacase ofmicrocephalyduringprenatalcare.49

Ontheotherhand,thepostnataldiagnosisusedtobe deter-minedbythecutoffofHCvaluelowerorequalto33cm.But recentlytheMOHdecreasedthisnumbertolessthanorequal to32cm,thesamevalueproposedbytheWHO,consequently avoidingunnecessaryexposuretopotentially harmfultests inchildrenwithnormalskull.WhentheHCofthenewborn isbelowthethirdpercentileorlessthanorequalto32cm, itisconsideredasuspectedcaseassociatedwithZIKV infec-tion,anditisconfirmedthroughpositivesamplesforthevirus inthe newbornor inthe mother duringpregnancy. Babies withcongenitalmicrocephalyshouldhavesamplesofblood, umbilicalcord,cerebrospinalfluid,andplacentacollectedat birthandanalyzedbyZIKVserology,which,ifpositive,should be further subjected to molecular biology analysis.44 _The preferredimagingexamistransfontanellarultrasonography (US-TF)inordertoavoidexposuretocomputedtomography scan (CT-scan).For those babies who present early-closing fontanelorifthesuspicionpersistsafterdiagnosticlaboratory andimagingtests,cranialCT-scanwithoutcontrastshouldbe performed.50_However,_the_São_Paulo_SESA_recommends_the executionoflaboratorytestsinvolvingmerelytheumbilical cord,placenta,andcerebrospinalfluid(CSF).49 _On_the_other hand,thePernambucoSESAadvisethatonlyCSFandblood ofthefetusandthemother’sbloodshouldbetested,andthe firstimagingevaluationtobedoneiscranialCTscanwithout contrast.5

Asstated,suspectedandconfirmedcasesofmicrocephaly relatedtoZIKVinfection mustbenotified.Thenotification shallberecordedintheonlineformofPublicHealth Event Log(RESP-Microcefalias),availableonwww.resp.saude.gov.br

and SINASConlinesystem.Thisisextremelyimportantfor epidemiological understanding of the featuresof this viral infection, sincethis data willbe storedin agovernmental database.44

TheMOHendurestheoperationofnonspeciﬁclaboratory testsfornewbornswithmicrocephaly,whichare:complete blood count,serumlevelsofliveraminotransferases,direct and indirect bilirubin, urea, creatinine, and indicators of inﬂammatoryactivity,aswellasanabdominalultrasoundand echocardiography.44_The_Pernambuco_SESA_also_recommends rapidtestforsyphilisand/orVDRL.5_The_technical_report_of theStateofSãoPaulodoesnotspecifywhichlaboratorytests mustbemadeinthenewborn.49

Additionally,asmicrocephalymayberelatedto neurode-velopmentaldisorders,theAuditoryEvokedPotentialtesting (BAEP) should beperformed as the ﬁrstchoice forhearing assessment, in addition to the Ocular Neonatal Screening Test,forophthalmicevaluation,andtheBiologicalNewborn ScreeningTest.50_The_São_Paulo_SESA_does_not_specify_any_of thesetests,49_while_Pernambuco_SESA_emphasizes_the impor-tance of ophthalmologic examination with fundoscopy in newbornswithmicrocephaly.5

Acaseofstillbirthwithmicrocephalyatanygestationalage isdeemedsuspectedifthemotherhadahistoryofrashillness duringpregnancy.Anysuspectedcasesmustbereported,and shouldundergoconﬁrmationtestsforZIKVidentiﬁcationin themotherorfetaltissue.Forthispurpose,theMOH recom-mends collectingsamples of1cm3 from the child’s organs (brain,liver,heart,lung,kidneyandspleen)and3cm3_from_the

placenta formolecular and immunohistochemistry biology tests,inadditiontotheserologicalevaluationofthemother.44 In regard tothis detection, the Pernambuco’sProtocolalso recommendsthatbaby’stissuesamplesandplacentashould be collected but it does not mention the mother’s serum testing,5_while_the_São_Paulo_SESA_has_no_{recommendation} onstillbirthsinitstechnicalreport.49

Incaseofapositivehistoryforrashduringpregnancy fol-lowedbyanabortion,theMOH considersitasasuspected abortionrelatedtoZIKVinfection.Itisconﬁrmedonlywhen thepathogenisidentiﬁedinmaternalorfetaltissue. There-fore,itisnecessarytocollectsamplesinthesamewayasfor thecasesofstillbirthswithZIKVrelatedmicrocephaly.44_The SãoPauloandPernambucoSESAhavenotpublished recom-mendationsforthissituation.5,49

Themosteffectiveplantocombatthisoutbreakof micro-cephalypossiblycausedbyZIKVistheprevention,ﬁghtingthe Aedessp.mosquitobyeradicatingtheirbreedinggrounds.51 Itisessentialforthecommunitytobeorientedonthe con-trolofmosquitoproliferationinurbanandperi-urbanareas. Forthisreason,publichealthactions,suchashomevisitsby healthprofessionals,advisingandguidingthepopulationto eliminatevectorsourcesinsidethehousesshouldbe imple-mented.Additionally,usinginsecticidessprayedbyvehicles on publicroadsand urbansanitationcampaignsshouldbe contemplated.44,52

TheMOHendorsesinstructingfertilewomen,whowishto haveachild,aboutthecurrentsituationofmicrocephalyin thecountry.5,50_Health_authorities_do_not_request_to_postpone pregnancy,althoughthereisdiscussionregardingthissubject, especiallyforyoungcouples whocould planforpregnancy

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afterbest knowledgeandcontrol ofthisvirus. Itis impor-tant forhealthcare professionals to inform the population ingeneralabout thedisease,belyingunofﬁcial information andcheckingtheofﬁcialdatafromepidemiologicalbulletins released weekly (available in www.saude.gov.br/sus). More-over,itisparticularlyimportanttomakeanearlydiagnosis ofmicrocephalyandrecognizepossiblebraindysfunctionsto guidethepatienttoahealthcareunitthatcanimplementearly brainstimulationmeasures.50

Furthermore,forpersonalprotection,mainlyforpregnant women, the MOH suggests using topical repellent prod-ucts,registeredatthe NationalHealth SurveillanceAgency (ANVISA).Itisimportant toinstructthe patients tofollow the recommendations on the label and to spray insect repellent on top of the clothing. Researches demonstrate safetyofn-diethyl-meta-toluamide(DEET)-basedrepellents. Nonetheless,othersubstancesare alsousedinBrazil,such as hydroxyethyl isobutyl piperidine carboxylate (icaridin or picaridin) and ethyl butylacetylaminopropionate(IR3535 or EBAAP), and essential oils such as citronella. Even if theseproducts are safeforregular use, there are no stud-ies in pregnant women. The CDC informs that repellents containingDEET,picaridin,IR3535,someoiloflemon euca-lyptusandpara-menthane-diolproductsprovidelonglasting protection.44,53

Besidesrepellenttopicaluse,otherformsofpreventionare alsoimportant.Itissuggested,wheneverpossible,theuseof longclothes toprotectthelargest bodysurface aspossible againstmosquito’sbites.Placesandtimeswiththepresence ofmosquitoesshouldbeavoided,consequentlyitisimportant tostayinlocationswithbarriersagainsttheentryofinsects, mainlyintheperiodbetweensunsetanddawn,asprotective screens,mosquitonets,andairconditioning.44,50

Incaseofanyalterationinthehealthconditionofpregnant women, especiallyuntil the fourth monthof pregnancy, it shouldbereportedforthehealthprofessional.51_It_is impor-tanttopositthatdefectsintheCNSmayalsobecausedby otherconditionsanddiseases,suchastoxoplasmosis,rubella, abuseofalcoholandillicitdrugsduringpregnancy,andalso geneticsyndromesthatmakedifferentialdiagnosiswiththose conditionsassociatedwithZIKV.5

Conclusion

TherelationbetweenZIKVinfection duringpregnancyand microcephaly in neonates was established by the Brazil-ianMOH. Therefore, more attention regarding Aedes sp. is required,sinceittransmitsthisdisease,whichhasmore disas-trousconsequencesthanDENVinfection.Also,thepregnant woman should be concerned about exposure to endemic areas,andifpossible,avoidremaininginsuchlocations.Since thereis still no evidence about the period ofvulnerability oftheembryo’sdevelopment,theprotectionbyusing repel-lentsinanepidemicsituationiscrucialthroughoutpregnancy. Notably,itisworthemphasizingthatmoreresearchis warr-antedtostudyviralmechanismsofactiononnewbornsand intheirdevelopment,becausealthoughmicrocephalycanbe easilydiagnosedinthedeliveryroom,otherpossibledamage tothefetuscanbenotsoevident.

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1.MinistériodaSaúde.MinistériodaSaúdeconﬁrmarelac¸ão entrevírusZikaemicrocefalia.Availablefrom:http:// portalsaude.saude.gov.br/index.php/cidadao/principal/

agencia-saude/21014-ministerio-da-saude-conﬁrma-relacao-entre-virus-zika-e-microcefalia[accessed16.12.15].

2.GubioSC,AntonioCB,SilviaIS.Zikavirusoutbreak,Bahia,

Brazil.EmergInfectDis.2015;21:1885–6[letter].

3.SecretariadeVigilânciaemSaúde-MinistériodaSaúde. BoletimEpidemiológico.Monitoramentodoscasosde dengue,febredeChikungunyaefebrepelovírusZikaatéa SemanaEpidemiológica48,2015.Availablefrom:http://

portalsaude.saude.gov.br/images/pdf/2016/janeiro/07/2015-svs-be-pncd-se48.pdf[accessed16.12.15].

4.Ministériodasaúde.Conﬁrmac¸ãodoZikavírusnoBrasil. Availablefrom:http://portalsaude.saude.gov.br/index.

php/cidadao/principal/agencia-saude/17701-conﬁrmacao-do-zika-virus-no-brasil[accessed16.12.15].

5.SecretariaEstadualdeSaúdedePernambuco.Secretaria

ExecutivadeVigilânciaemSaúde.ProtocoloClínicoe

Epidemiológicoparainvestigac¸ãodecasosdemicrocefaliano

estadodePernambuco.VersãoN◦_02._Pernambuco:_Secretaria

EstadualdeSaúde;2015,42pp.

6.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦11/2016–semana epidemiológica04/2016(24a30/01/2016).Availablefrom: http://portalsaude.saude.gov.br/images/pdf/2016/fevereiro/

03/COES-Microcefalias—Informe-Epidemiol–gico-11—SE-04-2016—02FEV2016—18h51-VDP.pdf[accessed05.02.16].

7.CentersforDiseaseControlandPrevention.Symptoms. Availablefrom:http://www.cdc.gov/zika/symptoms/index. html[accessed22.12.15].

8.MussoD,RocheC,RobinE,etal.Potentialsexual

transmissionofZikavirus.EmergInfectDis.2015;21:359–61.

9.DuffyMR,ChenTH,HancockWT,etal.Zikavirusoutbreakon

YapIsland,FederatedStatesofMicronesia.NEnglJMed.

2009;360:2536–43.

10.Protocoloparaimplantac¸ãodeunidadessentinelasparaZika vírus.Availablefrom:http://portalsaude.saude.gov.br/images/ pdf/2015/dezembro/14/Protocolo-Unidades-Sentinela-Zika-v–

rus.pdf[accessed20.12.15].

11.OehlerE,WatrinL,LarreP,etal.Zikavirusinfection

complicatedbyGuillain–Barresyndrome–casereport,French

Polynesia,December2013.EuroSurveill.2014:2014[rapid

communications].

12.LopesN,NozawaC,LinharesREC.Característicasgeraise

epidemiologiadosarbovírusemergentesnoBrasil.Rev

Pan-AmazSaude.2014;5:55–64.

13.CentersforDiseaseControlandPrevention.Forhealthcare providers:diagnostictesting.Availablefrom:

http://www.cdc.gov/zika/hc-providers/index.html[accessed

16.12.15].

14.GourinatAC,O’ConnorO,CalvezE,GoarantC,

Dupont-RouzeyrolM.DetectionofZikavirusinurine.Emerg

InfectDis.2015;21:84–6.

15.MussoD,NhanT,RobinE,etal.PotentialforZikavirus

transmissionthroughbloodtransfusiondemonstratedduring

anoutbreakinFrenchPolynesia,November2013toFebruary

(7)

16.FoyBD,KobylinskiKC,ChilsonFoyJL,etal.Probable

non-vector-bornetransmissionofZikavirus,Colorado,USA.

EmergInfectDis.2011;17:880–2.

17.VasconcelosPFC.Editorial.Doenc¸apelovírusZika:umnovo

problemaemergentenasAméricas?RevPan-AmazSaude.

2015;6:9–10.

18.Fiocruz–FundaçãoOsvaldoCruzhomepage.IOC/Fiocruz identificaapresençadeZikavírusemdoiscasosde microcefalia.Availablefromhttp://portal.fiocruz.br/pt-br/

content/iocﬁocruz-identiﬁca-presenca-de-zika-virus-em-dois-casos-de-microcefalia[accessed09.12.15].

19.SweetRL,GibbsRS.Infectiousdiseasesofthefemalegenital

tract.5thed.Baltimore,MD:LippincottWillims&Wilkins;

2009.p.266–300[perinatalinfections].

20.PanAmericanHealthOrganization.WorldHealth

Organization.Epidemiologicalalert.Neurologicalsyndrome,

congenitalmalformations,andZikavirusinfection.

ImplicationsforpublichealthintheAmericas;2015,

December,11pp.

21.BarthelA,GourinatAC,CazorlaC,etal.Breastmilkasa

possiblerouteofverticaltransmissionofDenguevirus.Clin

InfectDis.2013;57:415–7.

22.CenterforDiseaseControlandprevention.PossibleWestNile

virustransmissiontoaninfantthroughbreast-feeding–

Michigan,2002.MorbMortalWklyRep.2002;51:877–8.

23.SecretariaEstadualdeSaúdedoParaná.Superintendênciade

vigilânciaemsaúde.Protocolodevigilânciaerespostaà

ocorrênciademicrocefaliarelacionadaàinfecc¸ãopelovírus

Zika(protocolocomplementaraodoministériodasaúde).

Versão1.3.Paraná:SecretariaEstadualdeSaúde;2015,44pp.

24.AshwalS,MichelsonD,PlawnerL,DobynsWB,Practice

Parameter.Evaluationofthechildwithmicrocephaly(an

evidence–basedreview).Neurology.2009;73:887–97.

25.WoodsCG,ParkerA.Investigatingmicrocephaly.ArchDis

Child.2013;98:707–13.

26.AbueloD.Microcephalysyndromes.SeminPediatrNeurol.

2007;14:118–27.

27.EuropeanCentreforDiseasePreventionandControl.Rapid

riskassessment:microcephalyinBrazilpotentiallylinkedto

theZikavirusepidemic–24November2015.Stockholm:

ECDC;2015,12pp.

28.MinistériodaSaúde.MinistériodaSaúdeinvestigaaumento decasosdemicrocefaliaemPernambuco.Availablefrom: http://portalsaude.saude.gov.br/index.php/cidadao/principal/

agencia-saude/20629-ministerio-da-saudeinvestiga-aumento-de-casos-de-microcefalia-em-pernambuco[accessed

20.12.15].

29.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦01/2015–semana epidemiológica46(15a21/11/2015).Availablefrom:http:// portalsaude.saude.gov.br/images/pdf/2015/novembro/24/ COES-Microcefalias—Informe-Epidemiol–gico—SE-46—

24nov2015.pdf[accessed10.12.15].

30.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦02/2015–semana epidemiológica47(22a28/11/2015).Availablefrom:http://

portalsaude.saude.gov.br/images/pdf/2015/novembro/30/coes-microcefalias—informe-epidemiol–gico—se-47.pdf[accessed

10.12.15].

31.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦03/2015–semana epidemiológica48(29/11/2015a05/12/2015).Availablefrom: http://portalsaude.saude.gov.br/images/pdf/2015/dezembro/ 08/COES-Microcefalias—Informe-Epidemiol–gico—SE-48—

08dez2015.pdf[accessed10.12.15].

32.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦04/2015–semana epidemiológica49(06a12/12/2015).Availablefrom:http:// portalsaude.saude.gov.br/images/pdf/2015/dezembro/15/ COES-Microcefalias—Informe-Epidemiol–gico—SE-49—

15dez2015—10h.pdf[accessed20.12.15].

33.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦05/2015–semana epidemiológica50(13a19/12/2015).Availablefrom:http:// portalsaude.saude.gov.br/images/pdf/2015/dezembro/28/

coes-microcefalias-informe-epidemiologico-se50-21dez2015-18h.pdf[accessed05.02.16].

34.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦06/2015–semana epidemiológica51(20a26/12/2015).Availablefrom:http:// portalsaude.saude.gov.br/images/pdf/2015/dezembro/30/ COES-Microcefalias—Informe-Epidemiol–gico—SE-51—

29dez2015—15h.pdf[accessed05.02.16].

35.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦_07/2015_–_semana

epidemiológica52(27/12/2015a02/01/2016).Availablefrom: http://portalsaude.saude.gov.br/images/pdf/2016/janeiro/05/ COES-Microcefalias—Informe-Epidemiol–gico-07—SE-52—

04jan2016.pdf[accessed05.02.16].

36.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦08/2016–semana epidemiológica01/2016(03a09/01/2016).Availablefrom: http://portalsaude.saude.gov.br/images/pdf/2016/janeiro/13/ COES-Microcefalias—Informe-Epidemiol–gico-08—SE-01-2016

—Valida----o-12jan2016—VALIDADO-PELO-CLAUDIO–e-com-os-estados-por-webconfer–n.pdf[accessed05.02.16].

37.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦09/2016–semana epidemiológica02/2016(10a16/01/2016).Availablefrom: http://portalsaude.saude.gov.br/images/pdf/2016/janeiro/21/ COES-Microcefalias—Informe-Epidemiol–gico-SE-02-2016.pdf [accessed05.02.16].

38.CentrodeOperac¸õesdeEmergênciasemSaúdePúblicasobre Microcefalias.Monitoramentodoscasosdemicrocefaliasno BrasilinformeepidemiológicoN◦10/2016–semana epidemiológica03/2016(17a23/01/2016).Availablefrom: http://portalsaude.saude.gov.br/images/pdf/2016/janeiro/28/ COES-Microcefalias—Informe-Epidemiol–gico-10—SE-03-2016

—26jan2016—20h34.pdf[accessed05.02.16].

39.DickGWA.Zikavirus(II).Pathogenicityandphysical

properties.TransRSocTropMedHyg.1952;46:521–34.

40.HughesRAC,CornblathDR.Guillain–Barrésyndrome.Lancet.

2005;366:1653–66.

41.GérardinP,BarauG,MichaultA,etal.Multidisciplinary

prospectivestudyofmother-to-childChikungunyavirus

infectionsontheislandofLaRéunion.PLoSMed.

2008;5:413–23.

42.ParsonsonIM,Della-PortaAJ,SnowdonWA.Congenital

abnormalitiesinnewbornlambsafterinfectionofpregnant

sheepwithAkabanevirus.InfectImmun.1977;15:

254–62.

43.WasayM,KhatriI,Abd-AllahF.Arbovirusinfectionsofthe

nervoussystem:currenttrendsandfuturethreats.

Neurology.2015;84:421–3.

44.MinistériodaSaúde.SecretariadeVigilânciaemSaúde.

DepartamentodeVigilânciadasDoenc¸asTransmissíveis.

(8)

microcefaliarelacionadaàinfecc¸ãopelovírusZika.Brasília:

MinistériodaSaúde;2015,55pp.

45.SadlerTW.EmbriologiaMédica–Langman.7thed.Riode

Janeiro:GuanabaraKoogan;1997.p.250–3[Chapter20,

SistemaNervosoCentral].

46.FacciniLS,RibeiroEM,FeitosaIML,etal.Possibleassociation

betweenZikavirusinfectionandmicrocephaly—Brazil,

2015.MorbMortalWklyRep.2016;65:59–62.

47.CentersforDiseaseControlandPrevention.Factsabout microcephaly.Availablefrom:http://www.cdc.gov/ncbddd/

birthdefects/microcephaly.html[accessed05.02.16].

48.PanAmericanHealthOrganization.WorldHealth

Organization.Zikavirus(ZIKAV)surveillanceintheAmericas:

interimguidanceforlaboratorydetectionanddiagnosis;

2015,4pp.

49.SecretariaEstadualdeSaúdedeSãoPaulo.Coordenadoriade

ControledeDoenc¸as.CentrodeVigilânciaEpidemiológica.

InstitutoAdolfoLutz.Vigilânciadasmicrocefalias

relacionadasainfecc¸ãopelovírusZika.InformeTécnico01.

SãoPaulo:SecretariaEstadualdeSaúde;2015,12pp.

50.MinistériodaSaúde.SecretariasEstaduaiseMunicipaisda Saúde.Protocolodeatendimento:mulheresemidadefértil, gestantes,puérperasebebescommicrocefalia.Available from:http://www.corengo.org.br/wp-content/uploads/

2015/12/Procolo-de-Atendimento-14122015.pdf[accessed

21.12.15].

51.SecretariaEstadualdeSaúdedoParaná.Orientac¸ãoàs

EquipesdeSaúdesobreMicrocefalia.NotaTécnicaSESAN◦

01/2015i.Paraná:SecretariaEstadualdeSaúde;2015,8pp.

52.MinistériodaSaúde.SecretariadeVigilânciaemSaúde.

DepartamentodeVigilânciaEpidemiológica.Diretrizes

nacionaisparaprevenc¸ãoecontroledeepidemiasde

dengue/MinistériodaSaúde,SecretariadeVigilânciaem

Saúde,DepartamentodeVigilânciaEpidemiológica(SérieA.

NormaseManuaisTécnicos).Brasília:MinistériodaSaúde;

2009,160pp.

53.CentersforDiseaseControlandPrevention.Prevention. Availablefrom:

http://www.cdc.gov/zika/prevention/index.html[accessed