Introduction
There are limited data on young people who inject drugs (
PWID
) from low‐ and middle‐income countries where injection drug use remains a key driver of new
HIV
infections. India has a diverse injection drug use epidemic and estimates suggest that at least half of
PWID
are ≤30 years of age. We compared injection and sexual risk behaviours and
HIV
incidence between younger and older
PWID
and characterized uptake of
HIV
testing and harm reduction services to inform targeted
HIV
prevention efforts.
Methods
We analysed cross‐sectional data from 14,381
PWID
recruited from cities in the Northeast and North/Central regions of India in 2013 using respondent driven sampling (
RDS
). We compared “emerging‐adult” (18 to 24 years, 26% of sample) and “young‐adult”
PWID
(25 to 30 years, 30% of sample) to older
PWID
(>30 years, 44% of sample) using logistic regression to evaluate factors associated with three recent risk behaviours: needle‐sharing, multiple sexual partners and unprotected sex. We estimated age‐stratified cross‐sectional
HIV
incidence using a validated multi‐assay algorithm.
Results
Compared to older adults, emerging‐adults in the Northeastern states were significantly more likely to share needles (males adjusted odds ratio [
aOR
] 1.82; females
aOR
2.29,
p
<
0.01), have multiple sexual partners (males
aOR
1.56; females
aOR
3.75,
p
<
0.01), and engage in unprotected sex (males
aOR
2.29,
p
<
0.01). In the North/Central states, young‐adult males were significantly more likely to needle‐share (
aOR
1.23,
p
<
0.05) while emerging‐adult males were significantly more likely to have multiple sexual partners (
aOR
1.74,
p
<
0.05). In both regions, emerging‐adults had the lowest
HIV
testing. Participation in harm reduction services was low across all age groups. Annual
HIV
incidence was higher in emerging‐ and young‐adult
PWID
in the North/Central region: emerging‐adults: 4.3% (95% confidence interval [
CI
] 3.0, 5.6); young‐adults: 4.9% (95%
CI
3.7, 6.2); older adults: 2.1% (95% CI 1.4, 2.8).
Conclusions
Higher
HIV
incidence an...