Marked increase in first-timeMarked increase in first-timeHIV diagnoses in Ontario, 2002HIV diagnoses in Ontario, 2002Jane Njihia, Robert S. Remis, Carol Swantee,Margaret Fearon, Carol Major, Keyi Wu, Mark Fisher

Health Canada, HIV Laboratory, Laboratories Branch, Ontario Ministryof Health and Long-term Care, Etobicoke and Department of PublicHealth Sciences, University of Toronto, Toronto, Ontario

12th Annual Canadian Conference on HIV/AIDS ResearchHalifax, Nova Scotia, April 10-13, 2003

AcknowledgementsAcknowledgements

• Public Health Laboratory staff, Public Health Laboratory staff, Ontario Ministry of Health and Long-Term CareOntario Ministry of Health and Long-Term Care

• Keyi Wu, programmingKeyi Wu, programming• Mark Fisher, systems consulting and custom downloadMark Fisher, systems consulting and custom download

BackgroundBackground

• In Ontario, HIV diagnostic testing is conducted at the HIV In Ontario, HIV diagnostic testing is conducted at the HIV Laboratory and regional labsLaboratory and regional labs

• Use HIV Laboratory data to monitor the HIV epidemics in Use HIV Laboratory data to monitor the HIV epidemics in OntarioOntario

• In late 2002, observed a marked increase in first-time In late 2002, observed a marked increase in first-time diagnoses in the first three quartersdiagnoses in the first three quarters

Study objectivesStudy objectives

1. To characterize the increase in first-time HIV diagnoses 1. To characterize the increase in first-time HIV diagnoses at the Ontario HIV Laboratory in 2002at the Ontario HIV Laboratory in 2002

2. To better understand to what extent this increase was due to 2. To better understand to what extent this increase was due to increased HIV testing or HIV incidenceincreased HIV testing or HIV incidence

MethodsMethods

• Examined first-time HIV-positive and total HIV tests Examined first-time HIV-positive and total HIV tests from 1985 to 2002from 1985 to 2002

• First-time HIV positive: confirmed positive with no link First-time HIV positive: confirmed positive with no link to a previous positive result in database and no other evidence to a previous positive result in database and no other evidence of previous HIV-positive test in Ontarioof previous HIV-positive test in Ontario

• Based on the observed pattern, defined the period of Based on the observed pattern, defined the period of increase as calendar year 2002increase as calendar year 2002

• Compared HIV test results for 2002 to those in 2001 by sex, Compared HIV test results for 2002 to those in 2001 by sex, age, exposure category, reason for testing, health region and age, exposure category, reason for testing, health region and seroconverter or notseroconverter or not

RESULTS First-time HIV positives and RESULTS First-time HIV positives and HIV tests by year, Ontario, 1985-2002HIV tests by year, Ontario, 1985-2002

0

500

1000

1500

2000

2500

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

Year of testing

Fir

st-t

ime

HIV

po

stiv

e te

sts

050000100000

150000200000250000300000

350000400000

All

HIV

tes

ts

First-time HIV positives All HIV tests

First-time HIV positives and HIV testsFirst-time HIV positives and HIV tests by quarter, Ontario, 1999-2002 by quarter, Ontario, 1999-2002

050

100150200250300350

1999

Q1

1999

Q2

1999

Q3

1999

Q4

2000

Q1

2000

Q2

2000

Q3

2000

Q4

2001

Q1

2001

Q2

2001

Q3

2001

Q4

2002

Q1

2002

Q2

2002

Q3

2002

Q4

Year-Quarter

Nu

mb

er o

f F

irst

-tim

e H

IV p

osi

tive

tes

ts

020000400006000080000100000120000140000

Nu

mb

er o

f al

l HIV

tes

ts

First-time HIV positives All Tests

First-time HIV diagnoses by sex First-time HIV diagnoses by sex Ontario, 2002 versus 2001 Ontario, 2002 versus 2001

Year Female Male Unknown Total2001 254 733 31 1,0182002 317 880 32 1,238

Relative rate (2002/2001) 1.28 1.20 1.03 1.22

Excess tests (2002-2001) 72 147 1 220

First-time HIV diagnoses by health region First-time HIV diagnoses by health region Ontario, 2002 versus 2001Ontario, 2002 versus 2001Year Northern Eastern Ottawa Central East Toronto South Central

Other Other West West

2001 22 38 147 74 604 65 632002 24 30 164 70 809 53 84

Relative rate (2002/2001) 1.09 0.79 1.12 0.95 1.34 0.82 1.33

Excess tests (2002-2001) 2 2 17 -4 205 -12 21

Proportion of Excess 0.80% 6.90% 83.70% 8.60%

First-time HIV diagnoses by exposure category First-time HIV diagnoses by exposure category by year, Ontario, 1985-2002by year, Ontario, 1985-2002

0

200

400

600

800

1000

1200

1400

1985

1986

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

1997

1998

1999

2000

2001

2002

Year of testing

Nu

mb

er o

f fi

rst-

tim

e p

osi

tive

s

Unknown MSM IDU Endemic HR Hetero LR Hetero

First-time HIV diagnoses by exposure First-time HIV diagnoses by exposure category , Ontario, 2002 versus 2001category , Ontario, 2002 versus 2001Year MSM IDU Endemic HR hetero LR hetero Unknown

2001 221 35 36 24 99 5562002 317 37 45 26 107 660

Relative rate (2002/2001) 1.43 1.06 1.25 1.08 1.08 1.19

Excess tests (2002-2001) 96 2 9 2 8 104

Proportion of Excess 42.7% 0.9% 4.0% 0.9% 3.6% 46.2%

First-time HIV diagnoses by reason for testing, First-time HIV diagnoses by reason for testing, Ontario, 2002 versus 2001 Ontario, 2002 versus 2001 Year Donor of

blood, tissue Diagnostic Follow-up Insurance Prenatal semen Visa (Known) Unknown

2001 380 31 2 11 2 6 8 578 2002 447 40 2 8 0 119 12 610

Relative rate (2002/2001) 1.18 1.29 1.00 0.73 0.00 19.83 1.50 1.06

Excess tests (2002-2001) 67 9 0 -3 -2 1 13 4 32

Is the the increase due to an increase Is the the increase due to an increase in HIV testing?in HIV testing?

Number of first-time HIV diagnoses in Ontario, compared to numberof HIV tests by year of test

Increase from previous yearYear First time HIV

diagnosesOverall HIV

testingFirst time HIVdiagnoses

Overall HIV testing

1998 995 287,7891999 922 279,220 -7% -3%2000 938 262,763 2% -6%2001 1018 280,084 9% 7%2002 1238 337,447 22% 20%

Summary of increase in major categoriesSummary of increase in major categories

Comparing 2002-2001, proportional increase in first-time diagnoses with HIVtesting among categories with marked increase

Variable Category First-time HIV diagnoses HIV testsMSM 43% 8%Exposure categoryEndemic 25% 6%

Reason for testing Visa 1983%(119 vs. 6)

2541%(32,888 vs. 1294)

Toronto 34% 34%Central West 33% 15%

Region

Ottawa 12% 11%

Proportion of seroconverters, linked and in Proportion of seroconverters, linked and in progress, among first-time HIV diagnoses progress, among first-time HIV diagnoses 2002 versus 2001 2002 versus 2001

Linkedseroconverters

178 202

1.13 24

Seroconversionin progress

(ESC/RSC)

40 65

1.63 25

Linkedseroconverters

%

17.5% 16.3%

First-time HIVpositives

1018 1238

1.22 220

Seroconversionin progress

%

3.9% 5.3%

2001 2002

Relative rate Excess

Summary of observationsSummary of observations

• Excess of 220 (+22%) first-time HIV diagnoses from Excess of 220 (+22%) first-time HIV diagnoses from 2001 to 2002 2001 to 2002

• Exposure category: MSM and persons from Exposure category: MSM and persons from HIV- HIV-endemic regions (PHER) highestendemic regions (PHER) highest

• Health region: Toronto and Central West highestHealth region: Toronto and Central West highest• Reason for test, visa applicants highestReason for test, visa applicants highest• Reasons for testing and exposure categories were mutually Reasons for testing and exposure categories were mutually

exclusive, e.g., no MSM among visa applicantsexclusive, e.g., no MSM among visa applicants• Proportion of excess: MSM 43%, PHER 4%, visa 51%Proportion of excess: MSM 43%, PHER 4%, visa 51%

ConclusionsConclusions

• Increase among visa applicants entirely due to increase Increase among visa applicants entirely due to increase in in HIV testingHIV testing

• Among MSM and PHER, increase in HIV diagnoses Among MSM and PHER, increase in HIV diagnoses notnot due to increased HIV testing due to increased HIV testing• Increases in these groups may be due to selective increased Increases in these groups may be due to selective increased

HIV testing in persons at high risk for HIV infection HIV testing in persons at high risk for HIV infection • Also, evidence of increased HIV incidence in MSM Also, evidence of increased HIV incidence in MSM • Thus, both increased HIV testing and increased HIV incidence Thus, both increased HIV testing and increased HIV incidence

responsible for observed increase in HIV diagnosesresponsible for observed increase in HIV diagnoses• Relative importance not clear; requires further studyRelative importance not clear; requires further study