Kolkata: Rapid spread of Hep C infection among street IDUs

[Guest guest]

Rapid spread of Hepatitis C infection among street injecting drug users

undergoing syringe-needle exchange as an intervention in Kolkata, India

Indian Council of Medical Research (ICMR) conducted a sero-prevalence

study of street injecting drug users (IDUs) of Kolkata city in 1996

which revealed the prevalence of HIV, Hepatitis-B and Hepatitis-C was 1%,

8% and 17% respectively (1,2). Following this, a local community-based

organisation (CBO) started needle-syringe exchange programme in Kolkata

city as part of IDU intervention. Just five years following the onset

of above-said intervention, IDUs were further evaluated for HIV, Hep-B &

Hep-C in February 2002, which revealed that the prevalence of HIV,

Hepatitis-B & Hepatitis-C was 2%, 18% and 66% respectively. A weekly

surveillance of IDUs was established soon to monitor their risk behaviour and

to study the impact of intervention. After a gap of 11 months, same

cohort was re-screened in January 2003, which revealed a positivity of

80% (82 out of 102) with HCV infection among IDUs, while the prevalence

of HIV and Hepatitis B remained almost same as in 2002. HCV infection

was determined by 3rd generation ELISA test, Ortho HCV 3.0 ELISA

(Ortho-clinical Diagnostics GmbH, Neckargemund, Germany) using a combination of

recombinant HCV antigens (C 22-3, C 200 and NS 5). Due to cost

constraints, recombinant immunoblot assay (RIBA) could not be done for

confirmation of HCV infection. The specificity of repeat ELISA was >99% and

sensitivity was >95%.

Weekly surveillance data revealed that about 80% of the IDUs (N=140)

receive on an average daily two injections. About 95% of them do not

share their injecting equipment, while only 5% share with others. On an

average they share daily with 1.1 partners. But interestingly, about 50%

or more of our study subjects shares drugs from same ampoules (indirect

sharing) with others, primarily said to be due to lack of money which

forces them to share drugs from same ampoule to get kick. Under

needle-syringe exchange intervention, the IDUs are given fresh syringes and

needles daily by the trained outreach workers under supervision of field

supervisors. The same is taken back from IDUs next day after use. The

IDUs are also given free condoms, whenever they ask for it to promote

safer sex.

Although IDUs are at much higher risk of HCV infection [70-90%] (3),

the finding of continuous increase of HCV among IDUs of Kolkata in spite

of ongoing needle-syringe exchange intervention is really a matter of

concern. It has been observed that the prevalence of HCV was always much

higher than the corresponding HIV and HBV at any point of time screened

since 1996. The cause of current out of proportion of HCV increase is

poorly understood. However, followings risk behaviour was observed in

IDUs, which might accelerate the transmission of already higher

proportion of HCV compared to HBV & HIV. Firstly, through indirect drug sharing

from common ampoules, where the contaminated body fluid of one is mixed

with drug inside the ampoule and others draw it. Secondly, transmission

may be facilitated by the common small leftover earthen pot containing

water, which is frequently used for cleaning syringes & needles and

shared by IDUs before and after receiving injection. A third possibility

could be through the cotton swab (given along with fresh syringes to

IDUs) mixed with blood while using to stop post injection bleeding from

the femoral vein, is re-used by others to stop bleeding. Whatever could

be the reason/s, needle-syringe exchange intervention is appeared to be

not enough to control HCV transmission among IDUs, which needs to be

studied further in depth. A culturally suitable behavioural intervention

is urgently required to save IDU community from HCV infection, as there

is no protective vaccine against HVC infection at present.

Dr. Kamalesh Sarkar, MD

SRO/NICED/Kolkata

E-mail: <kamal412496@...>