6. HEALTH-CARE CONTEXT: HIV TESTING343 [6.2] Offering HIV testing and counselling in prisons is good practice, but it should never be mandatory. Isolation is not required for prisoners living with HIV/AIDS because infection does not usually occur through everyday physical contact, but by either unprotected sex or contaminated needles. This risk can be tackled by providing information and appropriate means of harm reduction, such as condoms, substitution treatment for those dependent on substances and clean injecting materials. Prisoners living with HIV/AIDS do not pose a risk to other prisoners as long as prisoners are properly informed about how to protect themselves and are given the appropriate means of prevention and harm reduction. Furthermore, when treated with antiretroviral therapy, which slows the spread of HIV in the body, HIV positive prisoners are no longer infectious and do not pose any HIV risk to third parties. Fitness to work determinations 28 Fitness to work determinations should be conducted on an individual basis, taking into account the physical and mental health of prisoners in evaluating their ability to undertake specific work tasks. 29 The requirement to determine fitness to work is raised in Rule 4(2), which specifies that all programmes, activities and services be delivered in line with the individual treatment needs of prisoners. 343. For more information on HIV testing and HIV in prisons, see: HIV prevention, treatment and care in prisons and other closed settings: a comprehensive package of interventions, UNODC/WHO/UNDP/ILO/UNAIDS, June 2013; Consolidated Guidelines on HIV Prevention, Diagnosis, Treatment and Care For Key Populations, WHO, July 2014 at www.who.int/hiv/pub/guidelines/keypopulations/en; WMA Statement on HIV/AIDS and the Medical Profession, 57th WMA General Assembly, October 2006 (amended October 2017) at www.wma.net/policies-post/wma-statement-on-hivaids-and-themedical-profession; UN Special Rapporteur on torture, A/HRC/22/53, op. cit., note 340, para. 71. 6 Guidance document on the Nelson Mandela Rules 149