ARGENTINA Number of registered AIDS cases. The number of officially registered cases is 10,889 (July 1997). The actual estimated number is 13,718. This 30% difference is accounted for by underregistration and delayed notification. Estimated number of HIV infected individuals. 120,000 people. Prevalence of different forms of HIV transmission. Sexual transmission, 46% (heterosexual, 51%; homosexual, 43%, and bisexual, 6%); bloodborne, 43% (IV drug abuse, 98%); vertical transmission, 6.7%, and unknown, 4.6%. Licensed ARV drugs. NRTIs: AZT, ddI, ddC, d4T, 3TC; PIs: Indinavir, Ritonavir, Nevirapine, Saquinavir. Current national guidelines. Yes, similar to those in USA. Developed by a consensus panel convened by the Ministry of Health and endorsed by medical associations. ARV drugs supply. ARV drugs are available through government agencies, social security, NGOs and private third-party payers. Viral load and CD4 determinations. Available in major cities. BRAZIL Number of registered AIDS cases. The official number reported by the National Epidemiological Bulletin of STD/AIDS program of Brazil is 110,872 cases from 1980 to March, 1997; 50% still alive. 70% distributed in south-eastern and southern states. Approximately 30% underreported. Estimated number of HIV infected individuals. Based on seroprevalence studies, 500,000 to 1,000,000 people. Prevalence of different forms of HIV transmission. Sexual transmission, 55% (homosexual, 32.6%; bisexual, 11.8%; heterosexual, 10.6%); bloodborne, 25% (transfusion, 3.1%; hemophilic, 0.7%; IV drugs abuse, 21.1%); unknown, 18%; perinatal, 2%. Male:female ratio, 4:1. Licensed ARV drugs. NRTIs: AZT, ddI, ddC, d4T, 3TC. PIs Saquinavir, Ritonavir and Indinavir. Current national guidelines. Yes, developed by the Ministry of Health Technical Experts Advisor Committee for the Management of ARV Drugs for HIV Infection Treatment. Summary: Initial ARV therapy for asymptomatic patients indicated or not depending on CD4 counts and VL. All symptomatic patients, irrespective of CD4 count or VL. Recommended regimens: dual therapy (2 NRTIs) as initial treatment for all patients, either symptomatic or asymptomatic. Triple therapy only for patients with evidence of advanced infection, irrespective of CD4 counts; symptomatic patients with CD4 <200 cells/ml, irrespective of VL; asymptomatic patients with CD4 <100 cells/ml, irrespective of VL; asymptomatic patients with CD4 <200 cells/ml and VL ³ 5,000 copies/mL. Patients on monotherapy should be switched to combination therapy, except those in whom combination therapy is not feasible; ddI, d4T and AZT are the drugs of choice for these patients. Nonresponsive patients on dual therapy should be switched to a triple combination, including a PI and, at least, one new NRTI. Indication of prophylaxis for occupational exposure should be based on the severity of the exposure. ARV drugs supply. The National Health Care System provides all drugs free of charge. A small proportion of patient receive them through private agencies. Viral load and CD4 determinations. 33 laboratories around the country provide screening and confirmatory testing. Half of them perform CD4 counts and VL (NASBA). At least one private or academic laboratory in state capital cities performs VL (RT-PCR or NASBA). MEXICO Number of registered AIDS cases. 31,807 (July, 1997). Estimated number of HIV infected individuals. 150,000 people. Prevalence of different forms of HIV transmission. Males: homosexual, 38%; heterosexual, 25%; bisexual, 26%; IV drugs abuse,10%. Females: sexual transmission, 54%; transfusions, 46%. Licensed ARV drugs. NRTIs: ddI, 3TC, d4T, ddC, AZT. PIs Indinavir, Ritonavir, Saquinavir. Current national guidelines. Yes, similar to those in the USA. Latest version revised in October 1996. New version due to publication in November 1997. Developed by the Council for AIDS, with participation of private and public agencies. ARV drugs supply. Mostly by Social Security (52%). Viral load and CD4 determinations. Currently available only in Mexico City. A laboratory network countrywide is being developed. PERU Number of registered AIDS cases. Since 1983, 5,700 cases. New cases in 1996, 1,050. Estimated number of HIV infected individuals. 100,000 people. Prevalence of different forms of HIV transmission. Sexual, 95%; perinatal and bloodborne, 2-5%. Licensed ARV drugs. NRTIs: AZT, ddI, ddC , d4T, 3TC. PIs: Ritonavir, Saquinavir. Current national guidelines. Only for prophylaxis of vertical transmission in HIV-infected pregnant women. Developed by public agencies. ARV drugs supply. Social Security and Army institutions. Viral load and CD4 determinations. CD4 available at the National Cancer Institute and private laboratories (U$S 100). VL available only in private laboratories (U$S 300).