Human immunodeficiency virus, hepatitis B and hepatitis C in an Indonesian prison: prevalence, risk factors and implications of HIV screening

Authors

  • Erni J. Nelwan,

    1.  Division of Tropical and Infectious Disease, Department of Internal Medicine, University of Indonesia, Jakarta, Indonesia
    2.  Health Research Unit, Medical Faculty, Padjadjaran University/Hasan Sadikin Hospital, Bandung, Indonesia
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  • Reinout Van Crevel,

    1.  Department of Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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  • Bachti Alisjahbana,

    1.  Health Research Unit, Medical Faculty, Padjadjaran University/Hasan Sadikin Hospital, Bandung, Indonesia
    2.  Department of Internal Medicine, Medical Faculty, Padjajaran University/Hasan Sadikin Hospital, Bandung, Indonesia
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  • Agnes K. Indrati,

    1.  Health Research Unit, Medical Faculty, Padjadjaran University/Hasan Sadikin Hospital, Bandung, Indonesia
    2.  Department of Clinical Pathology, Medical Faculty, Padjajaran University/Hasan Sadikin Hospital, Bandung, Indonesia
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  • Reiva F. Dwiyana,

    1.  Health Research Unit, Medical Faculty, Padjadjaran University/Hasan Sadikin Hospital, Bandung, Indonesia
    2.  Department of Dermatovenerology, Medical Faculty, Padjajaran University/Hasan Sadikin Hospital, Bandung, Indonesia
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  • Nisaa Nuralam,

    1.  Banceuy Narcotic Prison, Bandung, Indonesia
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  • Herdiman T. Pohan,

    1.  Division of Tropical and Infectious Disease, Department of Internal Medicine, University of Indonesia, Jakarta, Indonesia
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  • Ilham Jaya,

    1.  Banceuy Narcotic Prison, Bandung, Indonesia
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  • Andre Meheus,

    1.  Department of Epidemiology and Social Medicine University of Antwerp, Antwerp, Belgium
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  • Andre Van Der Ven

    1.  Department of Internal Medicine, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Corresponding Author Erni J. Nelwan, Division of Tropical and Infectious Disease, Department of Internal Medicine University of Indonesia, Jl, Diponegoro 71, Jakarta 10430, Indonesia. Fax: +62 21 3911873; E-mail: erninelwan@hotmail.com; ejnelwan@yahoo.com

Summary

Objective  To determine the prevalence and behavioural correlates of HIV, HBV and HCV infections among Indonesian prisoners and to examine the impact of voluntary counselling and testing for all incoming prisoners on access to antiretroviral treatment (ART).

Methods  In a non-anonymous survey in an Indonesian prison for drug-related offences, all incoming prisoners and symptomatic resident prisoners were counselled and offered testing for HIV, hepatitis B and C.

Results  Screening was performed in 679 incoming prisoners, of whom 639 (94.1%) agreed to be tested, revealing a seroprevalence of 7.2% (95% CI 5.2–9.2) for HIV, 5.8% (95% CI 3.9–7.6) for HBsAg and 18.6% (95% CI 15.5–21.6) for HCV. Of 57 resident prisoners tested, 29.8% were HIV-positive. HIV infection was strongly associated with injecting drug use (IDU; P < 0.001), but not with a history of unsafe sex. Screening of incoming prisoners was responsible for diagnosing and treating HIV in 73.0%, respectively, and 68.0% of HIV-positive individuals.

Conclusions  HIV and HCV are highly prevalent among incoming Indonesian prisoners and almost entirely explained by IDU. Our study is the first to show that voluntary HIV counselling and testing during the intake process in prison may greatly improve access to ART in a developing country.

Virus de l’immunodéficience humaine, hépatite B et hépatite C dans une prison indonésienne: prévalence, facteurs de risque et implications dans le dépistage du VIH

Objectif:  Déterminer les corrélats de prévalence et du comportement pour le VIH, le VHB et le VHC chez les détenus indonésien et examiner l’impact du conseil et dépistage volontaire pour tous les prisonniers entrants sur l’accès à l’ART.

Méthodes:  Dans une étude non-anonyme dans une prison indonésienne pour les infractions liées aux stupéfiants, tous les prisonniers entrants et résidents symptomatiques ont été conseillés et proposés un test de dépistage du VIH, de l’hépatite B et C.

Résultats:  Le dépistage a été effectué chez 679 prisonniers entrants, dont 639 (94,1%) ont accepté d’être testés, révélant une séroprévalence de 7,2% (IC95%: 5,2-9,2) pour le VIH, 5,8% (IC95%: 3,9-7,6) pour HBsAg et 18,6% (IC95%: 15,5-21,6) pour le VHC. Sur 57 prisonniers résidents testés, 29,8%étaient HIV séropositifs. L’infection par le VIH était fortement associée à l’usage de drogues injectables (UDI; p <0,001), mais pas avec une histoire de rapports sexuels non protégés. Le dépistage chez les prisonniers entrants a permis le diagnostic et le traitement du VIH chez 73,0%, soit 68,0% des personnes HIV séropositives.

Conclusions:  le VIH et le VHC sont très répandus chez les prisonniers entrants indonésiens et presque entièrement expliqués par l’UDI. Notre étude est la première à montrer que le conseil et dépistage volontaire du VIH au cours du processus d’admission en prison peut fortement améliorer l’accès aux antirétroviraux dans les pays en développement.

Mots-clés:  prisons, infections/*épidémiologie/*traitement du VIH, hépatite, viral, humain, toxicomanie, intraveineuse, Indonésie.

Virus de la inmunodeficiencia humana, hepatitis B y hepatitis C en una prisión de Indonesia: prevalencia, factores de riesgo, e implicaciones en el tamizaje para VIH

Objetivo:  Determinar la prevalencia y los factores correlacionados con el comportamiento de las infecciones por VIH, VHB, y VHC entre prisioneros Indonesios, y examinar el impacto del aconsejamiento y prueba voluntarios al momento del ingreso, y con acceso al TAR, para todos los nuevos prisioneros.

Métodos:  Como parte de una encuesta abierta sobre drogadicción realizada en una prisión de Indonesia, todos los prisioneros que ingresaban a la penitenciaría y aquellos residentes que eran sintomáticos recibieron aconsejamiento y se les ofreció el poder realizarse las pruebas para VIH, Hepatitis B y C.

Resultados:  Se realizó el aconsejamiento a 679 nuevos prisioneros, de los cuales 639 (94.1%) accedieron a realizarse la prueba, dando una seroprevalencia de 7.2% (95% IC 5.2–9.2) para VIH, 5.8% (95% IC 3.9–7.6) para el antígeno HBsAg y 18.6% (95% CI 15.5–21.6) para el VHC. De 57 prisioneros residentes a los que se les realizó la prueba, 29.8% eran VIH-positivos. La infección por VIH estaba significativamente asociada al uso de drogas inyectables (UDI; p<0.001), pero no a una historia de sexo inseguro. El tamizaje de nuevos prisioneros hizo posible el diagnóstico y el tratamiento del VIH en un 73.0% y 68.0% respectivamente de individuos VIH positivos.

Conclusiones:  El VIH y el VHC predominan entre los nuevos prisioneros en Indonesia, y la mayoría de los casos pueden explicarse en su totalidad al UDI. Nuestro estudio es el primero que muestra que el aconsejamiento y prueba voluntarios en una prisión puede aumentar y mejorar el acceso al TAR en un país en vías de desarrollo.

Palabras clave:  prisiones; infección / epidemiología/ terapia del VIH; hepatitis, viral, humana; abuso de sustancias, intravenoso; Indonesia

Introduction

The prevalence of HIV and other bloodborne infections is generally higher among prisoners than in the general community because of the over-representation of injecting drug users (IDUs) in prisons (Dolan et al. 2007). In high-income countries, prisons are therefore an important site to screen for HIV infection and initiate antiretroviral treatment (ART), as a way to increase access to HIV care (Springer et al. 2007; Zaller et al. 2007). Data regarding HIV and IDU from low-income and medium-income countries are less clear. For instance, studies on HIV prevalence rates among IDU prisoners are scarce and usually anonymous (Dolan et al. 2007), while reports of HIV/AIDS treatment programmes in prisons are limited to the outcomes of pilot projects (Spaulding et al. 2002; Springer et al. 2007) or include only patients with symptoms (Wilson et al. 2007).

This study was carried out in Indonesia, which has one of the fastest growing HIV epidemics in Asia (Pisani et al. 2003; AIDS Alert 2005). IDU is the main factor driving the epidemic in Indonesia, and patients are generally diagnosed at a very late stage of disease (Celentano et al. 2001; Pisani et al. 2003; Solomon et al. 2009). Prevalence rates above 50% have been reported among IDUs, while the HIV prevalence in the general population is fortunately still low (0.2%) (Mathers et al. 2008; Ministry of Health of Indonesia 2008). Other bloodborne infections such as hepatitis B and C (HCV) are also more common among IDUs compared to the general population (Allwright et al. 2000; Weinbaum et al. 2005; Butler et al. 2007). In 2006, more than 110 000 people were imprisoned in Indonesia, with around 30 000 convicted for drug-related offences, of whom 30–50% were IDUs (Directorate General of Correction 2007). Sentinel surveys have reported HIV prevalence rates up to 50% in Indonesian prisons (Ministry of Health of Indonesia 2007). However, these surveys were small and may have suffered from selection bias. HBV and HCV were not included in these surveys, no behavioural correlates were measured, and the implications of testing were not examined.

The aim of this study was therefore to determine the prevalence and behavioural correlates of HIV, HBV and HCV infections among Indonesian prisoners and to examine the impact of voluntary counselling and testing for all incoming prisoners on access to ART.

Materials and methods

Setting

The study was conducted in Banceuy prison, Bandung, one of the two prisons appointed for drug-related offences such as selling or dealing drug or drug use in West Java (40 million inhabitants), Indonesia. This prison has a maximum capacity for 450 prisoners, but at any point in time there are about 900–1000 prisoners and every month 30–50 new prisoners come in. Health care is provided in an outpatient clinic and in a small inpatient clinic by one general practitioner, two dentists and three nurses. Within 1 day after arrival, prisoners are medically examined and prisoners who are ill are admitted directly in the prison clinic. For HIV counselling and testing, the prison has collaborated with psychologists from Padjajaran University, Bandung, since 2004. Since 2006, Hasan Sadikin hospital in Bandung, the referral hospital for West Java, assists in the provision of health care by means of weekly consultation in prison by internists and other medical specialists, referral of patients to the hospital and training of nurses and a laboratory technician. Three additional physicians trained to provide counselling assisted during the conduction of the research in the clinic.

Cross-sectional survey

Between August 2007 and January 2009, a cross-sectional study was performed, with approval of the ethical committee of Padjajaran University, Bandung. All incoming prisoners were referred to the prison clinic, those who were symptomatic immediately and those who were asymptomatic within 3 months. In the clinic, prisoners were informed about the study and counselled about HIV. Written informed consent was asked for collecting medical and behavioural information and testing for HIV, HBV and HCV. If consent was given, information about sociodemographic data, medical history, physical status and risk behaviour related to HIV infection was recorded using a structured questionnaire. A physical examination was carried out, and blood was collected for serological testing. All testing was voluntary, free of charge and confidential, and counselling was performed before and after HIV testing.

Apart from the incoming prisoners, ‘resident’ prisoners (who had been in prison for at least 3 months in August 2007) were included if they presented at the prison clinic during the study period with symptoms or signs or self-reported risk behaviour related to HIV infection. These resident prisoners underwent the same procedure as the incoming prisoners. When the study was initiated in August 2007, there were 886 resident prisoners in Banceuy prison.

All HIV-positive subjects received further laboratory testing including the measurement of CD4 T-cell count. ART was started following national and WHO guidelines, under guidance from specialists at the Hasan Sadikin hospital.

Laboratory testing

HIV antibodies were measured using commercially available rapid tests (Determine HIV-1/2, Abbott laboratories, Tokyo, Japan; SD HIV-1/2 3.0, Standard Diagnostic, Inc, Kyonggi-do, Korea); enzyme immunoassay (EIA; Virolisa, Index Union Diagnostic, Korea); and electrochemiluminescence immunoassay (ECLIA; HIV combi, Roche, Mannheim, Germany) in accordance with national guidelines. HBsAg, anti-HBs, anti-HBc and anti-HCV were measured by ECLIA (Roche diagnostic, Mannheim, Germany). External quality control of HIV, HBV and HCV serology (National Serology Reference Laboratory, Australia) showed 100% accuracy. CD4 cell measurements were taken using Facscount flow cytometry technology (BD Biosciences, Jakarta, Indonesia).

Data analysis

The prevalence of infection with HIV, HBV and HCV was measured in the two groups of prisoners, the unselected group of incoming prisoners and the selected group of resident prisoners presenting to the clinic. Risk factors and symptoms were compared for seropositive and seronegative prisoners, using chi-squared test for nominal and ordinal variables, t-test for normally distributed and non-parametric Mann–Whitney U-test for non-normally distributed continuous variables. Multivariate logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI) for risk factors associated with infection. Data were analysed using SPSS, version 13.0 (SPSS) for windows.

Results

During an 18-month period, a total of 737 prisoners gave written informed consent to participate in the study, consisting of 679 incoming prisoners and 58 resident prisoners (Figure 1). After informed consent, 40 (5.9%) of the incoming prisoners refused a HIV test. Compared to those who agreed to be tested, fewer indicated a history of IDU (0%vs. 19.3%), fewer had been in prison before (15.8%vs. 20.2%), and fewer had physical symptoms suggesting possible HIV infection (data not shown). Among the 58 resident prisoners included, only one refused a HIV test.

Figure 1.

 Flow of incoming and resident prisoners. *Prisoners presenting at prison clinic with signs, symptoms and or risk behavior of HIV infection. ART, antiretroviral treatment.

The average age of the study population was 31.3 (range 17–63) years and 96.5% were men. Ten per cent had no formal education, 20% had graduated from elementary school, 30% had graduated from junior school, 35% were from high school, and 5% had been to university. More than half (51.4%) were married, and 9.7% were divorced or widowed. A history of IDU was reported by 19.3% of incoming prisoners. Twenty per cent of incoming prisoners had been in prison before, for a cumulative average of 8.3 (range 0.3–37.6) months. Twenty-two per cent of resident prisoners had been imprisoned before, and their cumulative average time spent in prison was 18.4 (7.0–32.0) months.

Seroprevalence of HIV, HBV and HCV infections

In Table 1, the seroprevalence of HIV, HBV and HCV is presented for incoming and resident prisoners. The seroprevalence rate for the incoming prisoners was 7.2% (95% CI 5.2–9.2) for HIV, 5.8% (95% CI 3.9–7.6) for HBV (HBsAg-positive) and 18.6% (95% CI 15.5–21.6) for HCV. HCV coinfection was strongly associated with HIV infection (P < 0.001). Regarding HBV infection, almost half of all incoming prisoners were positive for anti-HBs, anti-HBc or both. HBsAg-positive was not associated with HIV infection, but isolated anti-HBc antibody (anti-HBc alone) was more common in HIV-positive than in HIV-negative incoming prisoners (19.6 vs. 5.1%, P < 0.001). HBV–HCV coinfections were rare, both among HIV-positive and HIV-negative incoming prisoners (Table 1). Anti-HBc alone was more common in HCV-infected prisoners (14.3 vs. 5.0%; P < 0.001). Among the selected group of resident prisoners, the HIV prevalence was higher than among incoming prisoners, while infection with HBV and HCV appeared not much different (Table 1).

Table 1.   Seroprevalence of HIV, HBV and HCV
 Incoming prisoners (n = 639)Resident prisoners (n = 57)
  1. Data are shown as n/N (%).

HIV-positive 46/639 (7.2)17/57 (29.8)
 Anti-HCV-positive  41/46 (89.1)11/17 (64.7)
 HbsAg-positive   2/41 (4.9) 0
HIV-negative593/639 (92.8)40/57 (70.2)
 Anti-HCV-positive 77/593 (12.9) 4/40 (10.0)
 HbsAg-positive 30/565 (5.3) 1/37 (2.7)
HBsAg-positive 37/635 (5.8) 1/57 (1.8)
Anti-HBs and anti-HBc-positive222/635 (35.0)18/53 (34.0)
Isolated anti-HBc antibody 39/610 (6.3) 8/49 (16.3)
Anti-HBs alone 47/632 (7.4) 8/52 (15.4)
Any HBV marker-positive251/631 (39.8)20/53 (37.7)
Anti-HCV-positive118/635 (18.6)15/57 (26.3)
HBsAg and anti-HCV-positive  5/606 (0.8) 0
HIV, anti-HCV and HbsAg-positive  4/606 (0.7) 0

Signs, symptoms and risk behaviour according to serostatus

HIV-positive prisoners reported more symptoms associated with HIV (Table 2). A limited number of prisoners were examined for dermatological complaints; scabies was less and seborrhoic dermatitis was more common among HIV-positive prisoners.

Table 2.   Signs and symptoms of prisoners according to HIV serostatus
 HIV-positive (n = 63)HIV-negative (n = 633)P
  1. Data are shown as n/N (%).

Weight loss15/63 (25.9)56/626 (8.9)<0.001
Diarrhoea (>3 weeks) 5/59 (8.5)5/628 (0.8)<0.001
Fever (>1 month)13/59 (22.0)9/628 (1.4)<0.001
Chronic cough (>3 weeks)10/59 (16.9)28/628 (4.5)<0.001
Oral thrush7/59 (11.9)6/627 (1.0)<0.001
Scabies4/22 (18.2)67/179 (37.4)0.80
Seborrhoic dermatitis4/22 (18.2)9/176 (5.1)0.02

General characteristics and risk behaviour according to HIV status are shown in Table 3. A history of IDU was strongly associated with HIV infection; 37.6% of incoming prisoners who reported a history of IDU were HIV-infected, compared to 0.4% of those who denied IDU (P < 0.001). Information on frequency of needle sharing was collected but no association with HIV serostatus was found (data not shown). Among prisoners with a history of IDU, injecting in prison was more common in HIV-positive than in HIV-negative individuals (70.6 vs. 29.4%, P < 0.001). In univariate analysis, HIV-positive prisoners also more often had a history of previous imprisonment than HIV-negative prisoners (38.6 vs. 18.5%, P < 0.001) although the cumulative time spent in prison was similar in both groups. Unprotected sex with sex workers or casual partners was reported by more than 95% of prisoners in both groups.

Table 3.   Characteristics of prisoners according to HIV serostatus
 HIV-positive (n = 63)HIV-negative typo (n = 633)P
  1. Data are presented as n/N (%) unless stated otherwise.

Age (range, years)   28.0 (23–54)29.0 (17–63)0.33
Male 60/63 (95.2)612/633 (96.7)0.55
Previous imprisonment 22/57 (38.6)114/618 (18.5)<0.001
Cumulative time in prison (range, months)   8.5 (0.3–37.6)8.9 (0.4–65.7)0.94
History of injecting drug use58/61 (95.1)82/625 (13.1)<0.001
 Injecting in prison24/61 (39.3)10/625 (1.6)<0.001
Unprotected sex with sex worker60/63 (95.2)607/633 (95.9)0.80
Unprotected sex with casual partner55/63 (87.3)607/632 (96.0)0.002
Tattoo48/56 (85.7)341/621 (54.9)<0.001
Piercing 6/63 (9.5)87/633 (13.7)0.35

Multivariate analysis for factors associated with HIV infection is shown in Table 4. After adjustment for confounding IDU, other factors (previous imprisonment and tattoos) were no longer associated with HIV infection. Unprotected sex with sex workers was not significantly associated with HIV infection in univariate nor multivariate analysis.

Table 4.   Factors associated with HIV infection
 Crude OR95% CIAdjusted OR95% CI
  1. IDU, injecting drug use.

IDU128.039.2–418.1104.830.9–355.3
Previous imprisonment2.771.57–4.921.330.63–2.78
Tattoo4.912.28–10.551.740.71–4.23
Age1.020.98–1.050.980.93–1.04
Unprotected sex with sex worker0.280.12–0.711.870.48–7.4

HBV infection (detectable HBsAg) was not associated with IDU but was significantly more common among those with a tattoo (78.9 vs. 56.1%, P = 0.006), also after adjustment for IDU (adjusted OR 3.40 95% CI: 1.5–7.6, P = 0.03). Other risk factors such as previous imprisonment and unprotected sex with sex workers showed no significant association with HBV infection (data not shown). The same was true when prisoners who were positive or negative for any HBV marker were compared (data not shown). Similar to HIV, infection with HCV was more common among those with history of IDU (77.3 vs. 6.6%, P < 0.001), having a tattoo (81.4 vs. 51.7%; P < 0.001) or previous imprisonment (31.8 vs. 17.2%, P < 0.001). After adjustment for a history of IDU, having a tattoo remained significantly associated with HCV infection (adjusted OR 2.27, 95% CI 1.22–4.22), while previous imprisonment was no longer associated (adjusted OR 1.44, 95% CI 0.77–2.69). Among prisoners with a history of IDU, injecting in prison was more common in HCV-positive than in HCV-negative individuals (82.4 vs. 17.6%; P < 0.197). Unprotected sex with sex workers was associated with HCV infection in univariate analysis, but not after adjustment for confounding by IDU (adjusted OR 1.81, 95% CI 0.56–5.88).

Clinical implication of HIV testing

The median CD4 cell counts in the 63 HIV-positive prisoners were 246 cell/mm3 (range 5–726). Seventeen incoming (37·0%) and eight HIV-infected resident prisoners (47.0%) had a CD4 cell count <200/mm3, an indication to start antiretroviral therapy according to the Indonesian guidelines (Figure 1). Treatment was started in all prisoners with CD4 cells <200/mm3. Screening of incoming prisoners initiated diagnosing and treating HIV in 73.0%, respectively, and 68.0% of HIV-positive prisoners (Figure 1). Of 25 patients who started ARV in prison, no one stopped treatment (median follow-up 6.0 months, range 0–10), and all but one had an undetectable plasma HIV RNA after 6 months of treatment.

Discussion

High prevalence rates of HIV, HBV and HCV were found in an Indonesian prison. IDU was a very strong risk factor for HIV and HCV, but not HBV, while tattooing was independently associated with HBV and HCV infection. Unprotected sex with sex workers and others, although very commonly reported, was not a risk factor for HIV infection. Finally, HIV counselling and testing in prison revealed 73.0% of HIV diagnoses and started 68.0% of HIV treatment.

The willingness of prisoners to be tested was very high compared to studies performed elsewhere (Behrendt et al. 1994; Altice et al. 2005). This may be attributed to a comprehensive and stepwise approach in establishing HIV care. Before the study was started, prison policy and commitment were strengthened, good collaboration with health facilities outside prison was established, and general health care and counselling inside prison were improved (Nelwan et al. 2009). Both prison staff and prisoners were involved in the introduction of HIV testing and treatment. Testing can have a direct benefit for prisoners, but it also carries the risk of stigmatization (Morrison & Gilchrist 2001; Derlega et al. 2008). Unlike previous anonymous surveys (Behrendt et al. 1994), prisoners were informed about the results, and all those who were positive were tested for CD4 cell counts and offered treatment if indicated. As such, we demonstrate that also in low-income countries, prisons may offer a unique environment to improve access to care for IDU, thereby helping to bridge HIV prevention and control to the general community (Freudenberg 2001).

A high prevalence of HIV was found among unselected prisoners, much higher than among the general population in Indonesia (0.2%) (Ministry of Health of Indonesia 2008). Previous surveys of HIV prevalence in Indonesian prisons, including the prison where this study was conducted, showed higher figures (Direktorat Jendral Pemasyarakatan 2007; Dolan et al. 2007). However, these studies were much smaller and may have suffered from selection bias, with an over-representation of prisoners with physical symptoms or HIV-associated risk behaviour, like in the group of resident prisoners tested in this study (HIV prevalence 29.8%). The current figure of 7.2%, based on examination of 94.1% of incoming prisoners, is therefore more accurate to estimate the HIV prevalence among incoming prisoners. In most countries, HIV prevalence rates are higher in prison than in the general community (Dolan et al. 2007). However, the difference as found in this study is higher than in many other settings. For instance, in an anonymous recent survey in Thailand, 6.0% were found positive, compared to 1.5% among the general community in Thailand (Wilson et al. 2007) This is most likely due to the high percentage of IDUs in this prison and the strong association of HIV with IDU in Indonesia. In parallel, the higher prevalence of HIV among resident prisoners when compared to incoming prisoners in our study is maybe because of selection bias; alternatively, it may reflect ongoing HIV transmission in prison.

Similar to HIV, a much higher prevalence of HCV infection (18.6%) was found among incoming prisoners compared to the general population in Indonesia (2.1–3.9%) (Sulaiman et al. 1995; Akbar et al. 1997). HCV infection was predominantly found among IDUs, which made up 19·2% of prisoners. We also found that most HIV-positive incoming prisoners (89.1%) were HCV coinfected, in line with other reports on bloodborne infections in IDU (Thaisri et al. 2003). HCV was more common than HIV, which can be explained by the easier transmission of HCV through needle sharing among IDUs (Stark et al. 1996).

Almost 6% of prisoners were positive for HBsAg and around 50.0% for any marker of HBV infection. HBV was not associated with IDU, suggesting that HBV infection is not so much concentrated among IDUs but rather a more generalized problem maintained by sexual or vertical transmission. In addition to this, tattooing is common in prison populations and as reported elsewhere seems to be associated with HBV and HCV infections.(Samuel et al. 2001; Wilson et al. 2007) This is an important finding because the general awareness of the risk of tattooing is very low in Indonesia. Also in line with previous studies, anti-HBc alone was associated with HIV and HCV infections, possibly because of a deficient immune response in these conditions (Ferreira et al. 2009; French et al. 2009).

Injecting drug use was found to be the single strongest risk factor for HIV, typically reflecting the epidemic in Indonesia and the over-representation of IDUs in this prison. Almost 37.6% of IDUs entering this prison were already HIV-infected. Many reported previous imprisonment, often in other prisons. In addition, many prisoners reported ever having injected inside a prison, and this was independently associated with HIV infection, similar to studies in other settings (Thaisri et al. 2003). Clean needles are scarce in prison, as needle and syringe exchange programmes are not operational in most prisons, in Indonesia and abroad (Mesquita et al. 2007).

No other risk factors were associated with HIV infection. Previous imprisonment and tattoos were more common among HIV-positive prisoners but this was because of confounding by IDU. Unprotected sex with sex workers or casual partners was common but showed no association with HIV infection. However, many HIV-infected prisoners are married or have stable partners, and it is this category of ‘low-risk females’ who seem to have a substantial risk of becoming HIV-infected. This finding underlines the importance to focus HIV prevention in Indonesia on IDUs, through needle exchange, opioid substitution and condoms to protect their female partners.

This is one of the largest studies on bloodborne viruses in prison from a developing country. As only a single prison was included, the data are not representative of the whole of Indonesia and being cross-sectional, transmission inside prison could not be established with certainty. Also, the IDU status was determined by self-report and prisoners may be reluctant to admit a history of IDU, fearing possible consequences such as additional punishment. Despite these limitations, it can still be concluded that bloodborne viruses are common among Indonesian prisoners and that HIV prevention should primarily target IDUs. The data also confirm the need for HIV care (both testing and treatment) in prison, which is the exception rather than the rule in prisons in developing countries. Of note, also in western countries, the opportunity for timely diagnosis of HIV through screening in prison is often missed. For instance, screening is mandatory in prisons in South Carolina, USA, but almost 50% of 4000 subjects with a criminal record who were diagnosed with HIV infection in this state had not been screened during recent imprisonment. Feasibility and cost-effectiveness of more widespread screening for HIV in prisons should be evaluated, either for all prisoners or only for those with a history of IDU or symptoms suggesting HIV infection. HIV care should be combined with harm reduction programmes in prison, and more research is needed to identify the most effective strategies of harm reduction inside prisons. Continuation of ART after release from prison is another pressing issue also in western countries; a recent study showed that not more than 30% of Texas prison inmates receiving ART while incarcerated filled an initial ART prescription within 2 months of their release (Baillargeon et al. 2009).

In summary, HIV and HCV are highly prevalent in Indonesian prisoners and can almost entirely be explained by IDU. Tattoo was a risk factor for HBV and HCV infection. Unprotected sex, although almost universally reported, was not associated with HIV infection but may contribute to spread of HIV from IDUs or increased risk of IDUs’ sexual partners in the general community. Finally, voluntary counselling and testing of incoming IDU prisoners seem a feasible and effective way to increase the detection and treatment of HIV among prisoners.

Acknowledgements

We thank Bambang Krishbanu, Ilham Djaja, Sambiyono, Iqbal Djamaris and Beni Benardi for allowing and assisting the study in Banceuy Narcotic Prison Bandung. We thank Prof. Cissy B. Sudjana Prawira, director of the Hasan Sadikin General Hospital, Bandung, Indonesia, and Dr. Eri Surahman, Dean of the Medical Faculty Universitas Padjajaran, for accommodating and encouraging research in their institutions. We highly value the assistance and companion of Harry Suherman, Fedri Rinawan, Aly Diana, Ahmad Isa, Aries Sulaiman, Nopi Susilawati, Irma Utama, Yanti Siti Rismayanti, Elfi Wulandari, Tuti Herawati, Nuning and Akhyar during the conduction of this study. This study was supported by ‘IMPACT’ (Integrated Management of Prevention And Care and Treatment of HIV/AIDS), a collaborative research and implementation program of Padjadjaran University, Bandung, Indonesia; Maastricht University and Radboud University Nijmegen, the Netherlands; and Antwerpen University, Belgium. IMPACT is funded by the European Commission (SANTE/2005/105-033) and contracted by CORDAID.

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