hiv burden in india

HIV Burden in India

Lalit DandonaProfessor/Chair, International Public Health

School of Public Health &George Institute for International Health

The University of Sydney

26 July 2007

Population / Public Health

• Disease / health distributionEpidemiology, biostatistics

• Society-health interactionsSocial, behavioural, environmental

sciences

• Population health interventionsHealth systems, health policy

Major tracks

HIV Studies in IndiaHIV Studies in India• Population-based assessment of HIV distribution and risk factors

• Risk behaviour of men who have sex with men and female sex workers

• Impact of HIV interventions, including economic analysis

To inform policies & programs

Background of HIV Burden in India

• UNAIDS estimated in 2006 that India had

the highest number of persons with

HIV (5.7 million), but with a 3-fold

plausibility range

• HIV estimates in India calculated by NACO

based predominantly on public sector

sentinel surveillance data

• No systematic comparison of this method

with population-based data

Population category

Sentinel surveillance based calculations by NACO*

2005 population(15-49 years)

HIV rate Number with HIV

Urban men 6,131,043‡ 0.0240 147,145

Urban women 5,881,092‡ 0.0200 117,622

Rural men 14,464,583‡ 0.0240 347,150

Rural women 14,178,474‡ 0.0200 283,569

Urban men with STI 391,343§ 0.2280 89,226

Urban women with STI 340,978§ 0.1900 64,786

Rural men with STI 972,539§ 0.2280 221,739

Rural women with STI 870,077§ 0.1900 165,315

Woman sex workers 117,635¶ 0.1280 15,057

Men who have sex with men 5,082# 0.0645 328

Total 43,352,845 0.0335 1,451,937

HIV Burden in Andhra Pradesh 2005: NACO

Population-based HIV Study in Guntur District (4.5 million pop)

Stratified random cluster sample to represent rural and urban populationsOf the 13,838 sampled persons 15-49 years of age, 12,617 (91.2%) participated

Rigorous quality control of field and laboratory procedures

Dandona L et al. BMC Medicine 2006; 4: 31

Data Collection

• September 2004 – September 2005

• Relevant ethics approvals

• Informed consent, interview, blood sample as dried blood spots (DBS)

• Demographic data, standard of living index (SLI), risk factors and health services

use history

Laboratory Analysis

• HIV antibody: Murex, Tridot HIV p24 antigen: Murex, Vidas HIV nucleic acid: Amplicor PCR

• Established laboratory procedures usedFortes et al. J Clin Microbiol 1989; 27: 1380-81Behets et al. J Clin Microbiol 1992; 30: 1179-82Panteleeff et al. J Clin Microbiol 1999; 37: 350-53Roth et al. Lancet 1999; 353: 359-63Quinn et al. AIDS 2000; 14: 2751-57

• Quality assurance procedures

Sampled men(3376)

Sampled women(3414)

Gave blood sample and

interview(3135, 92.9%)

Gave interview only

(62, 1.8%)

Gave blood sample only

(4, 0.1%)

Rural sampled(6790)

Did not participate

(175, 5.2%)



Gave interview only

(77, 2.3%)


(1, 0.0%)

Sampled men(3475)

Sampled women(3573)



Gave interview only

(107, 3.1%)


(0)

Urban sampled(7048)

Did not participate

(272, 7.8%)



Gave interview only

(138, 3.9%)


(0)

Did not participate

(231, 6.5%)

Did not participate

(159, 4.7%)

Participation Profile of Sample

High Risk Groups in SampleSample Participation (%) (%)

Men visited woman sex workerEver 18.7Last 6 months 2.7

Identified woman sex workers 0.14

Men who had sex with men 2.1

Men who sold sex to men 0.26

Transport-related job – men 7.0 91.3

Unskilled labourers 31.6 92.1

Other regularly mobile jobs 7.2 92.8

Participation rates similar across age groups and marital status

HIV-1(N = 221)

HIV-2(N = 14)

HIV-1 & HIV-2(N = 3)

Retested by fourth-generation ELISA (Vidas)

Negative(N = 2)

PCR (Amplicor)

Negative (N = 2)

Third-generation rapid test(Tridot)

Positive(N = 238)

PCR (Amplicor) for HIV nucleic acid in high-risk cases (N = 585)

Negative(N = 584)

Negative(N = 12,375)

10% for quality assurance withfourth-generation ELISA (Murex) and PCR (Amplicor) (N = 1,238)

Negative with ELISA & PCR

(N = 1,238)

Positive(N = 0)

Third-generation ELISA for HIV antibody (Murex)

Positive(N = 238)

Negative(N = 4)

Positive(N = 242)

Fourth-generation ELISA for HIV antibody/antigen (Murex)

(N =12,617)

Initially false positive

Positive(N = 1)

Positive(N = 2)

p24 antigen test (Vidas)

Positive(N = 2)

Confirmed positive with

PCR (Amplicor)

Results of HIV Testing

Men Women Total

ParticipantsHIV

positive

Adjusted HIV

preva-lence

%

95% confidenceinterval; design effect

ParticipantsHIV

positive

Adjusted HIV

preva-lence

%

95% confidenceinterval;

designeffect

Adjusted HIV

preva-lence

%

95% confidenceinterval;

designeffect

Rural 3139 54 1.570.86-2.28;

2.363178 50 1.71

1.18-2.24; 1.43

1.641.10-2.18;

2.86

Western region (Durgi)

733 6 0.81 763 7 0.97 0.890.06-1.72;

3.02

Central region 1527 38 2.58 1543 26 1.79 2.191.41-2.97;

2.30

(Mupalla) 757 21 2.73 776 15 2.03 2.391.19-3.59;

2.47

(Narsaraopet)

770 17 2.43 767 11 1.54 1.990.92-3.06;

2.36

Eastern region (Kollur)

879 10 1.23 872 17 1.94 1.580.45-2.71;

3.75

Urban 3096 76 2.111.50-2.72;

1.373204 61 1.67

1.22-2.12; 1.04

1.891.39-2.39;

2.13

Guntur 2358 61 2.45 2443 44 1.63 2.041.44-2.64;

2.29

Narsaraopet 738 15 1.91 761 17 1.83 1.870.95-2.79;

1.84

Total 6235 130 1.741.27-2.21;

1.806382 111 1.70

1.36-2.04; 1.21

1.721.35-2.09;

2.44

Age (years)

Men Women

ParticipantsHIV positive

(%)Participants

HIV positive (%)

15-19 1175 3 (0.26) 1159 10 (0.86)

20-24 1086 16 (1.47) 1162 25 (2.15)

25-29 972 18 (1.85) 1027 26 (2.53)

30-34 833 33 (3.96) 886 19 (2.14)

35-39 842 35 (4.16) 864 17 (1.97)

40-44 628 15 (2.39) 757 8 (1.06)

45-49 699 10 (1.43) 527 6 (1.14)

Total 6235 130 (2.09) 6382 111 (1.74)

Age Distribution of HIV

Guntur ANC vs. Population-based HIV Prevalence

• 2005 sentinel surveillanceHIV 3% (12/400)

• September 2004 – September 2005Among 10,504 women receiving PMTCT

(96.9% of new ANC registrations)

HIV 2.95% (95% CI 2.63-3.27%)

• Population-based HIV ratesAll 1.72% (95% CI 1.35-2.09%)

Men 1.74% (95% CI 1.27-2.21%)

Women 1.70% (95% CI 1.36-2.04%)

HIV & Standard of Living Index

• Entire sampleUp to 50th percentile of SLI: 2.58% Above 50th percentile of SLI: 1.20%

• HIV ratio for lowest-highest SLI quartilesUrban: 3.47Rural: 2.37

• SLI gradient relatively lower for rural men

Population-based sample

SLI quartiles (score range)

I (up to 16)

II (17-22)

III (23-29)

IV (30+)

Antenatal care services utilized Total (%)Number

(%)Number

(%)Number

(%)Number

(%)

Public sector hospitals* 152 (21.1) 68 (44.7) 46 (30.3) 28 (18.4) 10 (6.6)

Other options 570 (78.9) 144 (25.3) 140 (24.6) 159 (27.9) 127 (22.3)

Private health facility 512 (70.9) 112 (21.9) 121 (23.6) 153 (29.9) 126 (24.6)

Other public sector facilities 14 (1.9) 6 (42.9) 4 (28.6) 4 (28.6) 0

Check-up at home 8 (1.1) 7 (87.5) 1 (12.5) 0 0

No check-up 36 (5.0) 19 (52.8) 14 (38.9) 2 (5.6) 1 (2.8)

Data not available 55 15 (27.3) 24 (43.6) 11 (20) 5 (9.1)

Total 777 227 (29.2) 210 (27.0) 198 (25.5) 142 (18.3)

Population-based sample

SLI halves(score range)

Lower(up to 22)

Upper(23 or more)

Type of health services utilized NumberHIV positive

(%)Number

HIV positive (%)

Antenatal care by women

Public sector hospitals* 114 5 (4.39) 38 1 (2.63)

Other 284 3 (1.06) 286 3 (1.05)

Total 398 8 (2.01) 324 4 (1.23)

General health services by men

Public sector 325 18 (5.54) 165 4 (2.42)

Other 2831 70 (2.47) 2909 38 (1.31)

Total 3156 88 (2.79) 3074 42 (1.37)

General health services by women

Public sector 516 19 (3.68) 246 4 (1.63)

Other 2792 60 (2.15) 2827 28 (0.99)

Total 3308 79 (2.39) 3073 32 (1.04)

Private to Public Sector Referral

Public sector antenatal clinic attendees

Guntur city Narsaraopet town

Rural Number

(%)

Urban Number

(%)

Total Number

(%)

Rural Number

(%)

Urban Number

(%)

Total Number

(%)

Total 235 (100) 252 (100) 487 (100) 311 (100) 91 (100) 402 (100)

Visited private health facility previously for this pregnancy

95 (40.4) 83 (32.9) 178 (36.6) 112 (36.0) 28 (30.8) 140 (34.8)

Referred by private facility to public sector hospital for this pregnancy

37 (15.7) 16 (6.3) 53 (10.9) 63 (20.3) 8 (8.8) 71 (17.7)

Includes referrals due to HIV positive result and suspected HIV

Population category

Sentinel surveillance method Population-based study method

2005 population

(15-49 years)

HIV prevalence

Number with HIV

2005 population

(15-49 years)

HIV prevalence

Number with HIV

Urban men 370,005‡ 0.0360 13,320 373,926** 0.0210 7,852

Urban women 366,235‡ 0.0300 10,987 378,557†† 0.0162 6,133

Rural men 848,207‡ 0.0360 30,535 873,893‡‡ 0.0157 13,720

Rural women 828,055‡ 0.0300 24,842 880,365§§ 0.0170 14,966

Urban men with STI 23,526§ 0.2280 5,364

Urban women with STI 21,234§ 0.1900 4,034

Rural men with STI 56,821§ 0.2280 12,955

Rural women with STI 50,815§ 0.1900 9,655

Woman sex workers 7,003¶ 0.1320 924 9,420¶¶ 0.1320 1,243

Men who have sex with men 300# 0.0645 19

Prisoners – men 800## 0.1050 84

Hostel residents – men 5,000*** 0.0420 210

Hostel residents – women 5,000*** 0.0324 162

Under-sampled urban men 14,297††† 0.0420 600

Under-sampled rural men 30,943††† 0.0314 972

Total 2,572,201 0.0438 112,635 2,572,201 0.0179 45,942

HIV Burden in Guntur District

Did We Under-estimate HIV?

• Sampling and calculationsNo known bias in sampling method for population

Under-represented high risk groups added

Participation rate of other high risk groups not low

• Laboratory methodsEstablished storage and analysis methods used

Quality assurance procedures utilized

No obvious reason for under-estimation in our methods

HIV Over-estimation with Official Method

• STI clinic component added extra HIV to estimate

70% extra

• Profile of public ANC usersReferral of HIV positive and suspects46% extraHigher representation of lower SLI28% extra

Population-based HIV Studies in IndiaLocation Data

collection year(s)

Sampling approach Participation rate

Sample size

Number of HIV positive persons

Population HIV prevalence as % (95% confidence interval)*

Power of sample size to detect difference from antenatal HIV prevalence at 95% confidence level†

Comments

Tamil Nadu: 3 districts

1998 90 rural & urban clusters selected using probability proportional to size; selected households from each cluster invited for medical camp; first 25 adults 15-45 years old from each cluster who came to camp included in study

82.5% for selected households; not mentioned for eligible individuals

1,981 34 Age & gender adjusted:1.80 (0.89-2.71)

17% to detect 20% difference from 1% antenatal HIV prevalence

Selection bias likely due to medical camp sampling approach, making interpretation difficult

Grossly under-powered for reliable comparison with antenatal HIV prevalence

Tamil Nadu: 1 rural sub-district, 1 urban town

1999-2000 120 rural & urban clusters selected using probability proportional to size; 15-40 years old persons from randomly selected households included in study

90.9% of 3-40 years old; not mentioned for eligible 15-40 years old individuals

2,870 29 Crude:1.01 (0.44-1.58)


Grossly under-powered for reliable comparison with antenatal HIV prevalence

Karnataka: 1 district

2003 10 villages and 20 urban blocks selected with cluster sampling using probability proportional to size; 15-49 years old persons included in study; further details not published

59.8% of 6700 eligible 15-49 years old individuals

4,008 118 Crude:2.94 (2.12-3.76)

50% to detect 20% difference from 2.6% antenatal HIV prevalence

Poor participation rate makes interpretation difficult

Under-powered for reliable comparison with antenatal HIV prevalence

Andhra Pradesh: 1 district [This study]

2004-2005 5 sub-districts selected to represent strata in district, from which 66 rural & urban clusters selected randomly; 15-49 years old persons from randomly selected households included in study

91.2% of 13838 eligible 15-49 years old individuals

12,617 241 Age, gender & rural-urban adjusted:1.72 (1.35-2.09)


Adequately powered for reliable comparison with antenatal HIV prevalence

Can These Findings be Generalized?

• STI clinic component in HIV estimationNot used elsewhere in the world for HIV

estimation from sentinel surveillance

• Referral of HIV positive and suspectsA widespread phenomenon in India

• Higher representation of lower SLIData from nationwide RCH survey

States2005 pop (millions)

Sample of women

who provided

data regarding antenatal

care

% who received antenatal

care

Percent who

received antenatal

care at public sector

hospital†

Percent who

received ante-natal

care at other public sector

facilities

SLI of women who used

public sector hospital for

antenatal care

SLI of women who used any public sector

facility for antenatal care

2005 HIV estimate 15-49 years¶ (1000s)

% in lower SLI half

% in upper SLI half

% in lower SLI half

% in upper SLI half

Andhra Pradesh 80.0 5,476 95.1 23.9 9.0 62.4 37.6 64.1 35.9 1,452

Karnataka 56.0 7,543 90.5 24.7 13.4 61.0 39.0 65.3 34.7 640

Maharashtra 104.2 9,284 94.0 14.8 29.5 43.5 56.5 63.0 37.0 1,232

Tamil Nadu 65.2 7,480 99.3 29.7 26.2 70.4 29.6 74.5 25.5 366

Nationwide RCH Survey 2002-2004

State

2005 pop

15-49 years

millions

2005 median

ANC sentinel surveill-ance HIV

prev(%)

NACO 2005 HIV estimate

15-49 years

millions

Plausible estimate (low) Plausible estimate (high)

Change needed in ANC HIV rate to

estimate population prevalence

(% of ANC HIV prev)

Corr-ection factor

for ANC HIV prev

2005 HIV estimate

15-49 years

millions

Change needed in ANC HIV rate to

estimate population prevalence

(% of ANC HIV prev)

Corr-ection factor

for ANC HIV prev

2005 HIV estimate

15-49 years

millionsRefer-

rals SLI

Under-repres-ented high-risk

groupsRefer-

rals SLI

Under-repres-ented high-risk

groups

Andhra Pradesh 42.7 2.00 1.45 -33 -9 +5 0.63 0.54 -20 -5 +10 0.85 0.73

Karnataka 30.0 1.25 0.64 -33 -8 +8 0.67 0.25 -20 -4 +16 0.92 0.35

Maharashtra 55.0 1.25 1.23 -33 +5 +12 0.84 0.58 -20 +3 +24 1.07 0.73

Tamil Nadu 36.3 0.50 0.37 -33 -14 +20 0.73 0.13 -20 -8 +40 1.12 0.20

Total 3.69 1.50 2.01

Conservative Extrapolations to Estimate HIV Burden

Indicative Estimates for India

HIV estimate for India may be

3-3.5 million or lower instead of the

official estimate of 5.2 million 15-49 year

old adults or 5.7 million total

Dandona L et al. BMC Public Health 2006; 6: 308

Recommendations

• Drop STI clinic component in the HIV estimation

method used in India

• Plan strategic and scientifically sound

population-based HIV studies every 3-4 years in

India to provide correction factors for

ANC/PMTCT HIV rates to estimate burden

• Rethink HIV surveillance strategy for India

Recent National DHS Survey in India

• Sample of 103,000 men and women, 82% of

eligible persons, tested for HIV

• 0.3% of adults had HIV in population-based

sample; 0.4% after adjusting for under-

represented high-risk groups

• In early July 2007, based on calculations by NACO

& UNAIDS, the Health Minister announced HIV

burden for India as 2.5 million (2-3.1 million)

New Lower HIV Burden in India

• Resource need for treatment less than projected

• This freeing-up of resources could make relatively

more resources available for prevention

• Focus of HIV prevention efforts

• More scientific basis needed for dynamics of HIV

spread and impact of HIV interventions in India

Implications

Prevention vs. Treatment

Basic sciences 49.6%

Clinical sciences 47.1%

Public health 3.3%

Original Health Research OutputIndia 2002


Health Research Output

Impact factor Impact factorper million pop per billion GDP-PPP

India 5.6 2.0

Australia 991 39

Aus–Ind Ratio 175 20

India versus Australia - 2002


hiv burden in india

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