Impactofinfluenzastrainandpatientcharacteristicsontheriskofadmissionswithinfluenza.GlobalInfluenzaHospitalSurveillanceNetworkResults,2014-

2015influenzaseason

ThestudywasfundedbySanofiPasteur

Methods

Joan Puig-Barberà1, Elena Burtseva2, Hongjie Yu3, Selim Badur4, Jan Kyncl5, F. Xavier López-Labrador1,6, Maria Pisareva7,Svetlana Trushakova2, Benjamin J. Cowling8, Tulay Bagci9, Ainara Mira-Iglesias1, Elizaveta Smorodintseva7, Lidiya Kisteneva2,Luzhao Feng3, Sevim Mese4, Angels Natividad-Miralles1, Kirill Stolyarov7, Lyudmila Kolobukhina2, Peng Wu8, Kubra Yurtcu4,Lubov Voloshchuk7, Veronika Afanasieva2 , Qin Ying3, Anna Sominina7 for the Global Influenza Hospital Surveillance Study Group(GIHSN).

1 Fundación para el Fomento de la Investigación Sanitaria y Biomédica de la Comunidad Valenciana (FISABIO), Valencia, Spain. 2 D.I. Ivanovsky Institute of Virology FSBI (Federal State BudgetaryInstitution). “N.F. Gamaleya FRCEM” Ministry of Health of Russian Federation, Moscow, Russian Federation. 3 Division of Infectious Disease, Key Laboratory of Surveillance and Early-Warning onInfectious Disease, Chinese Center for Disease Control and Prevention, Beijing, China. 4 National Influenza Reference Laboratory, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey. 5Department of Infectious Diseases Epidemiology, National Institute of Public Health, Prague, Czech Republic. 6 Consorcio de Investigación Biomédica de Epidemiología y Salud Pública (CIBERESP),Instituto de Salud Carlos III, Madrid, Spain. 7 Research Institute of Influenza, Saint Petersburg, Russian Federation. 8 School of Public Health, Li Ka Shing Faculty of Medicine, The University of HongKong, Hong Kong Special Administrative Region, China. 9 Hacettepe Medicine Faculty – Ankara, Turkey

Abstract:P42

ResultsIntroductionThe Global Influenza Hospital SurveillanceNetwork (GIHSN) is a public-privatepartnership between various Public Healthinstitutions and Sanofi Pasteur. The maingoal of the GIHSN is to study influenzaepidemiology. During the 2014-2015 influenzaseason, in 24 hospitals in Russia Federation,Czech Republic, Turkey, China and Spain (Figure1), we screened consecutive admissionsfollowing a common protocol.

FundaciónparaelFomentodelaInvestigaciónBiomédicaySanitaria(FISABIO),Valencia,SpainPhone:+34961925968;e-mail:puig_joa@gva.es

http://gihsn.org

Figure 2. Studymethods flowchart

DiscussionInfluenza was a significant threat for all agegroups. Comorbidity increased the risk ofinfluenza and this was observed for allinfluenza strains. Pregnancy was an risk factorregardless of involved strain.A(H1N1)pdm09 was associated with a graterrisk of ICU admission and B/Yamagata-lineagewith an increased risk of respiratory failure.

Figure1.GlobalInfluenzaHospitalSurveillanceNetwork(GIHSN)

Eligible'patients'considered'for'inclusion:

All#consecutive#admissions#for#an#acute#processAdmitted#in#the#previous#48#hours

Chief#complaints#for#admission#possibly#related#to#a#previous#influenza#infection

Residents#in#the#predefined#study’s#catchment#area#(study#population#or#study#base)

Complies'with'inclusion'criteria:

Able#to#communicateInformed#consent#to#participate

Is#a#permanent#resident#(as#defined#in#the#site#protocol)

Not#institutionalizedNot#discharged#from#a#hospital#in#the#last#30#daysILI#symptoms#within#7#days#to#admission#(≥5#y#old)Admission#symptoms#within#7#days#to#admission#

(<5#y#old)

Study'procedures:

Common#standardized#questionnaire#Combined#respiratory#swabs

Site’s'reference'laboratorySemi;quantitative'real;time'reverse'

transcription'PCR

Influenza)positive

Influenza)subtype)or)lineage

Influenza)negative

Eligible:17,469

Excluded: 6,357 (36%)Noconsent:1,727(10%)

NoILI:3,189(20%)

Symptoms>7days:1,327(11%)

Included:9,589(55%)

Negative:7,413(77%)

Influenza:2,176(23%)

Recruitedoutsideseason:1,176(10%)

Records:21,611

Southernhemisphere:338

Noresident:256

Institutionalized:870

Previousadmission≤30days:3,016(15%)

Figure 3. FlowchartofadmissionsGIHSN2014-2015influenzaseason

0

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Epidemiological week

A(H1N1)pdm09 (n=121; 6%)A(H3N2) (n=1,243; 57%)A not subtyped (n=106; 5%) B/Yamagata-lineage (n=665; 30%)B/Victoria-lineage (n=11; 0.5%)B not subtyped (n=54; 2%)

Figure4. Numberofadmissionswithinfluenza,byvirusstrainandweek

CVD

COPD

Asthma

Immunosupression

Diabetes

Renal disease

Neuromuscular

Neoplasm

Cirrhosis

Autoinmune

Pregnancy

Obesity

factors

Strain/Risk

1.69 (1.45, 1.97)

1.56 (1.31, 1.86)

1.48 (1.11, 1.96)

0.69 (0.33, 1.43)

1.76 (1.46, 2.12)

1.84 (1.46, 2.32)

0.69 (0.43, 1.12)

1.26 (0.88, 1.81)

0.88 (0.54, 1.43)

2.18 (1.48, 3.19)

2.35 (1.51, 3.68)

1.52 (1.25, 1.86)

aOR (95% CI)

319

222

65

8

180

108

19

38

19

36

64

148

Influenza

admissions with

Number of

1.69 (1.45, 1.97)

1.56 (1.31, 1.86)

1.48 (1.11, 1.96)

0.69 (0.33, 1.43)

1.76 (1.46, 2.12)

1.84 (1.46, 2.32)

0.69 (0.43, 1.12)

1.26 (0.88, 1.81)

0.88 (0.54, 1.43)

2.18 (1.48, 3.19)

2.35 (1.51, 3.68)

1.52 (1.25, 1.86)

aOR (95% CI)

319

222

65

8

180

108

19

38

19

36

64

148

Influenza

admissions with

Number of

1.25 .75 1 2 5Adjusted odds ratio

Adjusted odds ratio (aOR)* of admission with A(H3N2)

CVD

COPD

Asthma

Diabetes

Renal disease

Neuromuscular

Neoplasm

Autoinmune

Pregnancy

Obesity

factors

Strain/Risk

0.77 (0.45, 1.32)

0.40 (0.18, 0.88)

0.96 (0.38, 2.43)

0.62 (0.29, 1.31)

0.28 (0.07, 1.16)

2.49 (1.15, 5.40)

1.11 (0.39, 3.15)

0.52 (0.07, 3.80)

3.31 (1.07, 10.21)

0.60 (0.27, 1.33)

aOR (95% CI)

18

7

5

8

2

8

4

1

11

7

Influenza

admissions with

Number of

0.77 (0.45, 1.32)

0.40 (0.18, 0.88)

0.96 (0.38, 2.43)

0.62 (0.29, 1.31)

0.28 (0.07, 1.16)

2.49 (1.15, 5.40)

1.11 (0.39, 3.15)

0.52 (0.07, 3.80)

3.31 (1.07, 10.21)

0.60 (0.27, 1.33)

aOR (95% CI)

18

7

5

8

2

8

4

1

11

7

Influenza

admissions with

Number of

1.25 .75 1 2 5Adjusted odds ratio

Adjusted odds ratio* of admission with A(H1N1)pdm

CVD

COPD

Asthma

Immunosupression

Diabetes

Renal disease

Neuromuscular

Neoplasm

Cirrhosis

Autoinmune

Pregnancy

Obesity

factors

Strain/Risk

0.87 (0.69, 1.10)

0.63 (0.47, 0.84)

0.83 (0.54, 1.27)

0.78 (0.34, 1.81)

0.50 (0.35, 0.72)

0.70 (0.47, 1.06)

1.22 (0.77, 1.94)

0.88 (0.53, 1.47)

0.79 (0.43, 1.48)

0.76 (0.37, 1.56)

3.74 (2.27, 6.16)

0.79 (0.58, 1.07)

ratio (95% CI)

Adjusted odds

109

60

24

6

34

27

22

17

11

8

69

50

Influenza

admissions with

Number of

0.87 (0.69, 1.10)

0.63 (0.47, 0.84)

0.83 (0.54, 1.27)

0.78 (0.34, 1.81)

0.50 (0.35, 0.72)

0.70 (0.47, 1.06)

1.22 (0.77, 1.94)

0.88 (0.53, 1.47)

0.79 (0.43, 1.48)

0.76 (0.37, 1.56)

3.74 (2.27, 6.16)

0.79 (0.58, 1.07)

ratio (95% CI)

Adjusted odds

109

60

24

6

34

27

22

17

11

8

69

50

Influenza

admissions with

Number of

1.25 .75 1 2 5Adjusted odds ratio

Adjusted odds ratio* of admission with B/Yamagata

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Age group (years of age)

A(H1N1)pdm09 (n=121; 6%) A(H3N2) (n=1,243; 57%) A not subtyped (n=106; 5%) B/Yamagata-lineage (n=665; 30%) B/Victoria-lineage (n=11; 0.5%) B not subtyped (n=54; 2%)

Figure 5. Proportion of admissionswith influenza, by strain and age

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.02

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dict

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roba

bilit

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ICU

adm

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0 10 20 30 40 50 60 70 80 90 100 110Age group

No influenza A(H1N1)pdm

A(H3N2) B/Yamagata

RT-PCR result

Predicted probailities by RT-PCR result

-.2

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.2

.4

.6

Pre

dict

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y of

in h

ospi

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eath

0 10 20 30 40 50 60 70 80 90 100 110Age group

No influenza A(H1N1)pdm

A(H3N2) B/Yamagata

RT-PCR result

Predicted probailities by RT-PCR result

-.005

0

.005

.01

.015

Pre

dict

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bilit

y of

AR

DS

0 10 20 30 40 50 60 70 80 90 100 110Age group

No influenza A(H3N2)

RT-PCR result

Predicted probailities by RT-PCR result

-.05

0

.05

.1

.15

Pre

dict

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roba

bilit

y of

res

pira

tory

failu

re

0 10 20 30 40 50 60 70 80 90 100 110Age group

No influenza A(H3N2) B/Yamagata

RT-PCR result

Predicted probailities by RT-PCR result

0

.02

.04

.06

Pred

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obab

ility

of IC

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dmis

sion

0 10 20 30 40 50 60 70 80 90 100 110Age group

No influenza A(H1N1)pdm

A(H3N2) B/Yamagata

RT-PCR result

Predicted probailities by RT-PCR result

-.2

0

.2

.4

.6

Pred

icte

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obab

ility

of in

hos

pita

l dea

th

0 10 20 30 40 50 60 70 80 90 100 110Age group

No influenza A(H1N1)pdm

A(H3N2) B/Yamagata

RT-PCR result

Predicted probailities by RT-PCR result

-.005

0

.005

.01

.015

Pred

icte

d pr

obab

ility

of A

RD

S

0 10 20 30 40 50 60 70 80 90 100 110Age group

No influenza A(H3N2)

RT-PCR result

Predicted probailities by RT-PCR result

-.05

0

.05

.1

.15

Pred

icte

d pr

obab

ility

of r

espi

rato

ry fa

ilure

0 10 20 30 40 50 60 70 80 90 100 110Age group

No influenza A(H3N2) B/Yamagata

RT-PCR result

Predicted probailities by RT-PCR result

Figure 6. Adjusted risk of admission with influenza, by strain,related to underlyingchronic conditions or risk factors.

Figure 7. Predicted probability of severe outcomes (intensive careunit (ICU) admission and respiratory failure) by age and strain

Theadjustedoddsratio(aOR)foradmissionwithinfluenzawasestimatedbylogisticregressionusingascomparisongroupinfluenzanegativeadmissionswithoutunderlyingconditions.Allestimateswereadjustedasbysex,site,numberofadmissionsinprevioustwelvemonths,smokinghabits,timetoswabandcalendartime.