However, a study of women attending a hospital in Nairobi, Kenya, following rape, has highlighted the fact that in many countries rape victims are not examined by a gynaecologist or an experienced police examiner and that no standard protocols or guidelines exist on this matter. The use of standard protocols and guidelines can significantly improve the quality of treatment and psychological support of victims, as well as the evidence that is collected. Comprehensive protocols and guidelines for female victims of assault should include:   In some countries, the protocol forms part of the procedure of a sexual assault evidence kit that includes instructions and containers for collecting evidence, appropriate legal forms and documents for recording histories. Examinations of rape victims are by their nature extremely stressful. The use of a video to explain the procedure before an examination has been shown significantly to reduce the stress involved. Issues concerning sexual violence need to be addressed in the training of all health service staff, including psychiatrists and counsellors, in basic training as well as in specialized postgraduate courses. Such training should, in the first place, give health care workers greater knowledge and awareness of sexual violence and make them more able to detect and handle cases of abuse in a sensitive but effective way. It should also help reduce instances of sexual abuse within the health sector, something that can be a significant, though generally unacknowledged, problem. In the Philippines, the Task Force on Social Science and Reproductive Health, a body that includes doctors, nurses and social scientists and is supported by the Department of Health, has produced training modules for nursing and medical students on gender-based violence. The aims of this programme are:   These training modules are built into the curricula for both nursing and medical students. For the nursing curriculum, the eleven modules are spread over the four years of formal instruction, and for medical students over their final three years of practical training. The possibility of transmission of HIV during rape is a major cause for concern, especially in countries with a high prevalence of HIV infection. The use of antiretroviral drugs following exposure to HIV is known in certain contexts to be reasonably effective. For instance, the administration of the antiretroviral drug zidovudine (AZT) to health workers following an occupational needle-stick exposure (puncturing the skin with a contaminated needle) has been shown to reduce the subsequent risk of developing HIV infection by 81%. The average risk of HIV infection from a single act of unprotected vaginal sex with an infected partner is relatively low (approximately 1.2 per 1000, from male to female, and around 0.5–1 per 1000 from female to male).