Prevalence of hepatitis B and C virus infections among military personnel

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

The

Brazilian

Journal

of

INFECTIOUS

DISEASES

Original

article

Prevalence

of

hepatitis

B

and

C

virus

infections

among

military

personnel

Livia

M.

Villar

_,

_Kycia

_Maria

_R.

_do

_Ó

_,

_Leticia

_P.

_Scalioni

_,

_Helena

_M.

_Cruz

_,

Moyra

M.

Portilho

_,

_Ana

_Carolina

_F.

_Mendonc¸a

_,

_Juliana

_C.

_Miguel

_,

Andreza

S.

Figueiredo

_,

_Adilson

_J.

_de

_Almeida

_,

_Elisabeth

_Lampe

a_{LaboratoryofViralHepatitis,Fundac¸ãoOswaldoCruz(FIOCRUZ),RiodeJaneiro,RJ,Brazil}

b_{SãoLucasHospital,Petrópolis,RiodeJaneiro,RJ,Brazil}

c_{Gaffrée&GuinleUniversityHospital,SchoolofMedicineandSurgery,UniversidadeFederaldoEstadodoRiodeJaneiro(UNIRIO),}

RiodeJaneiro,RJ,Brazil

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Articlehistory:

Received28December2014 Accepted13February2015 Availableonline10March2015

Keywords: HepatitisB HepatitisC Prevalence Militarypersonnel

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Background:DataregardingHepatitisBandCviruses(HBVandHCV)prevalenceamong

mil-itarypersonnelinBrazilarelacking,butthework-relatedriskofexposurecanbehigh.The objectiveofthisstudywastoestimatetheseroprevalenceofHBVandHCVandtherisk factorsassociatedtoHBVexposureamongBrazilianmilitarypersonnel.

Methods:Across-sectionalstudywasconductedandincluded433malemilitaryadultsaged

18–25yearsoldworkinginRiodeJaneiroduringOctober2013.Allindividualscompleteda questionnairetoassesstheirriskofexposureandprovidedabloodsampletoHBVandHCV testing.

Results:NoneoftheparticipantspresentedHBsAgoranti-HBcIgM,18(4.1%)werepositivefor

totalanti-HBc,247(57.0%)werepositiveforanti-HBs,and3(0.7%)wereanti-HCVreactive. ThemajorityofmilitarypersonnelwithpastHBVinfection(anti-HBcreactive)andHBV immunity(anti-HBsreactive)hadahistoryofpriordentalprocedures(88.9%and77.3%), consumptionofalcoholatleastonceaweek(50%and55.9%),andpracticedoralsex(61.1% and58.3%,respectively).Inaddition,anti-HBcpositivitywascommonamongindividuals withahistoryofsurgery(44.4%)andpracticeofanalsex(50%).Atunivariateanalysis,age groupwasassociatedtoanti-HBcandanti-HBspositivity.

Conclusions: LowratesofHBVandHCVinfectionwereobservedamongBrazilianmilitary

personnelincomparisontothegeneralBrazilianpopulation.HBVimmunityrateswere relativelylowindicatingtheneedforvaccinationcampaignsinthisgroup.

©2015PublishedbyElsevierEditoraLtda.

∗ _{Correspondingauthorat:LaboratoryofViralHepatitis,Hélio&PeggyPereiraPavillion,GroundFloor,OfficeB-09,FIOCRUZ,Av.Brasil,}

4365,Manguinhos,RiodeJaneiro,RJ210360-040,Brazil. E-mailaddress:lvillar@ioc.fiocruz.br(L.M.Villar).

http://dx.doi.org/10.1016/j.bjid.2015.02.002

Introduction

HepatitisB and Cviruses (HBV and HCV) share parenteral routeasacommonmodeoftransmission.Worldwide, approx-imately240millionpeoplearechronicallyinfectedwithHBV and130–150millionwithHCV.1,2 _{Apopulation-based}

multi-centric,epidemiologicalsurveywasconductedinthegeneral populationacross thefive geographicregions ofBraziland foundanoverallHBsAgseroprevalencerateof0.37%,7.4%of anti-HBc,and1.38%ofanti-HCVamongindividualsaged10–69 years.3,4

Prevalencestudiesoftheseblood-bornediseasesshowed certainriskgroupsandbehaviorsthatshouldbeconsidered asreasonsforconcernandtakenintoaccountwhen design-ingamoreappropriateepidemiologicalinvestigation.Inthis context, anti-HBc reactivity has been reported to be 1.7% among health professionals, 5.9% among beauticians, and 12.8%amongrecyclable wastecollectors.5–7 _Anti-HCV

sero-prevalencehasanarrowerrange:0.2%amongchildren,1.3% amongcrackusers,and1.4%amongtruckdrivers.8–10

Young menare group in whom it is very important to recognizeriskbehaviorsassociatedwithparenterally trans-mitteddiseases.Militarypersonnelofferareachableandoften nationallyrepresentativesamplefordiseasesurveillance.In Brazil,militaryserviceiscompulsory foroneyear formen aged17–20 years from all socialclasses. Brazilian military personnelarebeingsenttocountriesthatpresenthigh esti-matedprevalenceratesforHBVandHCVinfection,suchas ColombiawhereHBVprevalencewas18.6%11_andHaitiwith

HCVprevalenceof4.4%.12_{Thisgroupofindividualscouldbe}

moreexposedtotransmissibleinfectiousdiseasesduetotheir missions.13,14

HBV immunization was included in the Brazilian vac-cination schedule for newborns in 1996 and was also recommendedtomilitarypersonnelin2010.15 InBrazil,the coverageofhepatitisBvaccinationamongchildrenlessthan 18monthsoldvariesfrom80to95%accordingto socioeco-nomicstatus.16 _{Amongyoungadultmales intheAirForce}

inSouthBrazil,84%ofthemreportedathree-doseschedule ofHBVvaccinationwhile66.9%offire-fightersfromCentral BrazilhadserummarkersofHBVimmunity.17,18_Thus,inface

ofthe paucityof dataregardingHBV and HCV markersof infectionamongmilitarypersonnelinBrazil,thisstudywas conductedtoestimatetheprevalenceratesofHBVandHCV markersandriskfactors inmilitarypersonnelservingata militaryunitinRiodeJaneiroCity,insoutheastBrazil.

Methods

Studypopulation

Thisisacrosssectional,seroprevalencestudyandconsistedof 433militarymalepersonnelintheagerangeof18–25yearsold. Allofthembelongedtothelargestmilitaryunitconsideredto beacentralpointforrecruitsandofficerseducationinRiode JaneiroStateandoneoftheoldestunitsofBrazil.Inthisunit, approximately1200individualsareservingintheMilitary,the majorityofthembeingconscripts.

InBrazil,militaryserviceiscompulsoryandyoungmen havetodraftforservinginthearmedforces,mostofthemin theArmy,whentheyturn18,independentoflevelofeducation or socio-economicstatus.Afterconcludingthe recruitment process,thoseconscriptswhowereconsideredsuitablebya selectioncommissionbeginbasicmilitarytrainingatdifferent militaryunits.Thosewillingtopursueamilitarycareerwill remaininservice.

TherecruitmentforthisstudywasbeganinOctober2013 andallindividualsservingattheaforementionedunitwere invitedtoparticipateinthestudysoonaftertheirarrivalto thatmilitaryunit.Studyparticipantsweremale,aging18years ormore,andregisteredinthemilitaryservice.Thosenot con-sentingtoparticipatewereexcluded.

Questionnaire

A standardquestionnairewas submittedto thestudy sub-jects bytheteamofthisstudy beforebloodcollection.The questionnaire inquiredabout socio-demographic character-istics of the individuals (age, gender, educational status, income level, history of previous hepatitis) and risk fac-tors for hepatitis Band C [history of blood transfusion or bloodproducts,surgery,intravenousdruguse,haemodialysis, dental procedures,acupuncture, tattooing,piercing,alcohol consumption at least once per week, sexually transmitted diseases (STDs),sexualorientation,number ofsexual part-ners,condomusage,practiceoforaland/oranalintercourse, exposure to manicure/pedicure who used non-sterilized instruments,andsharingpersonalcareitemssuchas tooth-brushes,razors/blades,nailclippersorscissors].

Informationon HBVvaccination (vaccinationstatusand numberofdosesreceived)wascollectedthroughaself-report methodsincevaccinationcardsormedicalchartswerenot availableforconsultationatthetimeofenrolmentinto the study.

Bloodsamplingfordetectionserologicalmarkersofviral hepatitis

A blood sample (5mL) was taken from each subject by venipuncture using a vacutainer device. The sample was allowedtoclotforserumrecoveryandstoredat−20◦_Cuntil

analysis.

SerumsamplesweretestedforHBsAg,anti-HBcIgM,total anti-HBc,anti-HBs,andanti-HCVusingcommercial enzyme-immunoassay(ELISA)kits (Diasorin,Italy), accordingtothe manufacturer’sinstructions.Samplesfoundtobenegativeon thepreliminaryscreeningwereconsideredseronegativeand samplesinitiallytestedborderlineorpositivewereretested usingthesameassayinordertoconfirmtheseresults. Datacollectionandanalysis

TheprevalenceratesofHBV andHCVmarkerswere calcu-latedforthetotalstudypopulation.Continuousvariableswere reportedasthemean±standarddeviation.Descriptive statis-ticswere generatedforthe responses,and thechi-squared test (2_{) forindependence orfor trendwas usedto assess}

anti-HBsstatusbyusingtheStatisticalPackagefortheSocial Sciences(SPSSforWindows,release20.0;SPSS,Inc.,Chicago, IL,USA).Theresultswereconsideredstatisticallysignificant whenp<0.05.

Ethicalconsideration

EthicalapprovalwasgivenbytheFiocruzEthicalCommittee, RiodeJaneiro,Brazil.Allparticipantsweregivenverbal expla-nationontheobjectivesandmethodologyoftheresearchand were ensured about confidentiality, that their participation wasvoluntary,andtheyhadfullrighttowithdrawfromthe studyatanytime.Subjectswereincludedinthestudyafter obtainingsignedinformedconsent.

Results

Demographicandriskfactorscharacteristics

Thesocio-demographiccharacteristicsof433military person-nelareshowninTable1.Allindividualsweremaleandmostof themaged18–25years(75%),hadsecondaryeducation(64.9%), andreportedamonthlyfamilyincomeuptoU$850dollars (48.5%).

Onlysevenindividualsreportedahistoryofprevious hep-atitis,and onlyonehad reported HBV infection.Regarding HBVvaccination,139informedtobevaccinatedbutonly32 reportedthree-doseschedule.

TheriskfactorsofstudyparticipantsareshowninTable2. Themostprevalentriskfactorsreportedbytheparticipants were prior dental treatment (77.1%), practice of oral sex (59.1%),andalcoholconsumption(52.2%).

Onlysix individuals reported to be non-injectable drug users atthe moment ofthestudy.However,22 individuals reportedpreviousintravenousdruguse,and10ofthemused

onlyonce.Regardingsexualorientation,427(98.6%) individ-uals saidtobeheterosexual,and 256(59.1%)hadaregular partner. One hundred eighty-one (41.8%) individuals never usedcondomduringsexualintercourse,12(2.8%)hada his-toryofsexuallytransmittedinfections(STD),256(59.1%)and 145(33.5%)reportedoralandanalintercourse,respectively.

Thirtyindividualsadmittedtosharepersonalinstruments, liketoothbrushes,razororblades.Sixty-threeconscriptshad tattoo,70usuallyusemanicurists,and154hadpiercing.

Viralhepatitisprevalenceandriskfactors

All individuals tested negative for HBsAg or anti-HBc IgM markers;18(4.1%)wereanti-HBc/anti-HBsreactive,indicating previousHBVinfection,and247(57.0%)individualspresented isolatedpositivityforanti-HBs,showingHBVimmunity sec-ondary to vaccination. Anti-HCV was detected in three individuals,resultinginanoverallprevalenceof0.7%andtwo ofthemreportedillicitsubstancesuseinthepast.

ThemajorityofindividualspresentingpastHBVinfection andHBVimmunityhadhistoryofdentalprocedures(88.9% and 77.3%,respectively), consumption ofalcohol (50% and 55.9%,respectively),andpracticeoforalsex(61.1%and58.3%, respectively). In addition, anti-HBc positivity was common amongindividualspresentinghistoryofsurgery(44.4%)and practiceofanalsex(50%).Atunivariateanalysis,age-group wereassociatedtoanti-HBcandanti-HBspositivity(Table1).

Discussion

Studies conducted to determine HBV and HCV preva-lence have been widelyinvestigated inmany occupational groups6,8,18_{,butfewdataareavailableonitsprevalenceamong}

militarypersonnel.Thepresentstudydemonstratedthat57% ofBrazilianmilitaryindividualshad serologicalevidenceof

Table1–DemographiccharacteristicsofBrazilianmilitarypersonnelaccordingtoanti-HBVantibodies(totalanti-HBc andanti-HBs)seropositivity(n=433).

Characteristics Total n=433(%) TotalAnti-HBc positive n=18(%) p-value Anti-HBspositive n=247(%) p-value

Agegroup(years) 0.001 0.004

18–25 325(75.0) 10(55.5) 194(78.5) 26–32 42(9.7) 0(0.0) 27(10.9) 33–40 32(7.4) 3(16.7) 12(4.9) >40 34(7.9) 5(27.8) 14(5.7) Educationlevel 0.853 0.864 Pre-school 10(2.3) 2(11.1) 8(3.2) Primaryschool 105(24.3) 1(5.5) 59(23.9) Secondaryschool 281(64.9) 14(77.8) 156(63.2) College 33(7.6) 0(0.0) 22(8.9) Post-college 4(0.9) 1(5.5) 2(0.8) Familyincome 0.529 0.540 <U$850.00 210(48.5) 9(50.0) 121(49.0) U$851.00–1695.00 147(33.9) 4(22.2) 79(32.0) U$1696.00–2542.00 41(9.5) 3(16.7) 24(9.7) U$2543.00–3390.00 23(5.3) 1(5.5) 16(6.5) >U$3391.00 12(2.8) 1(5.5) 7(2.8)

Table2–Factorsrelatedtoanti-HBVantibodies(totalanti-HBcandanti-HBs)positivityamongBrazilianmilitary personnel(n=433). Items Total n=433(%) Anti-HBcpositive n=18(%) Anti-HBspositive n=247(%) Hemodialysis 4(0.9) 0(0.0) 3(1.2) Previoussurgery 99(22.9) 8(44.4) 58(23.5) Bloodtransfusion 8(1.8) 1(5.5) 4(1.6)

Dentaltreatmentprocedure 334(77.1) 16(88.9) 191(77.3)

Injectingdruguse 6(1.4) 0(0.0) 5(2.0)

Acupuncture 9(2.1) 0(0.0) 4(1.6)

Tattooing 63(14.5) 3(16.7) 38(15.4)

Alcoholabuse 226(52.2) 9(50.0) 138(55.9)

Previoussexuallytransmitteddisease 12(2.8) 0(0.0) 8(3.2)

Morethanonesexualpartnerperyear 140(32.3) 5(27.8) 90(36.4)

Unsafesexualintercoursea _{181(41.8) 6(33.3) 90(36.4)}

Oralintercoursepractice 256(59.1) 11(61.1) 144(58.3) Analintercoursepractice 145(33.5) 9(50.0) 87(35.2) Sharingpersonalcareitemsb _{30(6.9) 1(5.5) 18(7.3)}

Earring/piercing 154(35.6) 5(27.8) 92(37.2) Manicure/pedicure 70(16.2) 2(11.1) 41(16.6)

a _{Donotusecondomatsexualintercourse.}

b _{Toothbrushes,razors/blade,nailclippersorscissors.}

HBV immunity, probablydue to the inclusion ofHBV vac-cinationinchildhoodimmunizationprogram,sincemostof individualswereyoung.ThesamerateofHBVimmunitywas observedamongairforcepersonnelfromSouthBrazil,17_but

thisrate islowerthan the ratereportedamongSaudi Ara-biasoldiers(57.5%),fire-fightersfrom CentralBrazil(66.9%), Spanishmilitarypersonnel(78.3%).13,18,19

NowadaysthecoverageofhepatitisBvaccinationamong childrenlessthan18monthsofagevariesfrom80to95%,16_but

thelowprevalenceofHBVimmunityobservedinthepresent studyisprobablyduetothefacttheywerethefirstgeneration ofcompulsoryvaccination.

Aperson isconsidered immune toHBV when anti-HBs levelsareequalorgreaterthan10mIU/mLinserum,which maybeacquiredthroughHBVinfectionorpostvaccination. Ninety-eightpercentofinfantsachieve seroprotectionafter HBVvaccinationwithathree-doseschedule.20_{However,after}

completionofthevaccine schedule, anti-HBstitersdecline andmayfallbelowthisthreshold,sometimestoundetectable levels.21 _{Inthe presentstudy,32.1%ofindividualsreported}

previousHBV vaccination butonly7.4%ofthem had com-pletedthe schedule,and21.0%ofthempresentedanti-HBs reactivity(anti-HBslevelsequalorgreaterthan10mIU/mLin serum).HBVimmunityratesmaybe21.0%amongthosewho reporteda3-doseschedule,32.1%amongthosewhoreported HBVvaccinationand57%consideringthosewithdetectable anti-HBs.Theseresultsshowtheimportanceofanti-HBs test-ing in order to confirm HBV immunity since self-reported vaccinationcouldnotbeconfirmed.

Military personnel are more exposed to transmissible infectiousdiseasesduetotheirmissions.13,14_These

individ-uals are far from home and exposed to several infectious agents what could have an impact over virus heterogene-itysincetheycanimportnewvariants.Theseprofessionals mayserveasasourceofinfection,especiallyforSTDsince militaryinstallationsusuallyattractgatheringsofsex work-ers.

Inthepresentstudy,noconscriptwerepositiveforHBsAg oranti-HBcIgMmarkerswhileHBsAgprevalencewasfound tovaryfrom0.3%amongGreekmilitaryrecruits,2.8%among Turkishrecruits,and4%amongSaudiArabiasoldiers.22–24_The

findingthatallindividualsinthepresentstudytestednegative forHBsAgcouldbeexplained,atleastinpart,bytheageless than 25yearsofmoststudysubjects.HBV vaccinationwas becamepartofthevaccinationscheduletoallnewbornsin Brazilin1996andwasextendedtoindividualsagedupto20 yearsin2001.

HBVpastinfectionwasobservedin18(4.1%)youngmilitary males,afrequencylowerthanthatobservedamongSaudi Ara-biansoldiers(13.2%)19_{buthigherthanthatreportedamong}

militarypersonnelfromGreece(1.68%),andSpain(0%).13,22

Anti-HBcreactivitywasassociatedwithage-group.Thesame wasobservedamongrecyclablewastecollectors,7_indicating

thatovertime,thereisagreatertrendofacquiringHBV infec-tionrelatedtosexualandparenteralexposures.

Anti-HCV prevalencewas0.7%amongBrazilianmilitary personnel, aprevalencesimilar tothatreported bystudies conductedamongAfghanNationalArmyrecruits(0.8%)14_and

Peruvian Air Force, (0.2%),24 _{but this rate was lower than}

that documented among Pakistan Military Force (3.13%).25

Anti-HCVprevalenceamongBrazilianmilitarypersonnelwas lowerthantherate(1.38%)reportedforthegeneralBrazilian population4_{andsuggeststhatconscriptsarenotunderhigher}

risk forHCVinfection. Inaddition, mostanti-HCV positive individualsreportedpreviousintravenousdruguse, suggest-ingthatthisriskfactorcouldbethemodeoftransmissionin thissmallgroupofconscripts.Ourresultsreinforcetheneed foreducationprogramsinordertoavoidriskpracticesforHCV acquisitioninthispopulation.

Thepresentstudypresentssomelimitations.First,itmay be affectedbyselectionbias, asthe participantswere pre-dominantlyhealthyyoungadultmales.Therefore,theresults cannotbeextendedtotheBraziliangeneralpopulationorto specialpopulationsathighriskforHBVandHCVinfection,

suchasintravenousdrugusers,sexworkers,and hemodial-ysispatients.Second,validityofself-reportingdatasuchas HBVvaccinationandhistoryofviralhepatitismightbe com-promised byrecall bias sincethese informationswere not obtainedbyconsultingtheconscripts’records.Sinceanti-HBs levelscoulddeclineovertimeinvaccinatedindividuals,itis possiblethatsomeconscriptswithundetectablelevelsof anti-HBshavealreadybeen,infact,vaccinated.

Finally,vaccinationprogramsareimportantinthisgroup, sincetheseindividualsaremoreexposedtoviralinfections duringtheirduties.Inthiscontext,theycanplayanimportant roleonvirusepidemiologyeitherbyimportingorexporting HBVvariants.

Conclusion

Inconclusion,thisstudyshowsalowprevalenceofHBVand HCVinfectionamongBrazilianmilitarypersonnel,reflecting thesuccessofuniversalimmunizationtowardtheeradication ofHBV transmission. TherateofHBV immunitywas rela-tivelylowinthisgroupindicatingthe needforvaccination campaignstargetingtheseprofessionalsandtheimportance ofprevalencestudiesforHBVandHCVinfectioninorderto designeffectivepreventionandcontrolprograms.

Conflicts

of

interest

Theauthorsdisclosenocurrentorpotentialconflictof inter-est,including anyfinancial, personalorotherrelationships withpeopleororganizations,withintwoyearsofthe begin-ning ofthis study that couldinappropriately influencethe study.

Source

of

support

ThisresearchwassupportedbytheSupportFoundationfor ResearchofRiodeJaneiroState(FAPERJ),BrazilianNational CounselofTechnologicalandScientificDevelopment(CNPq) andtheOswaldoCruzFoundation(FIOCRUZ).

Acknowledgements

TheauthorswishtothankIsleneAzevedodeSouzaeSilva, MaristellaMatosdaCosta,NayhanneTizzodePaula,Sergio deAraujoPereira,VanessaDuartedaCosta,VithoriaVidotti Nevesfortechnicalassistanceindatacollection.

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