Kow-Tong Chen, M.D., Ph.D., Hsiao-Ling Chang, Ph.D., Chu-Tzu Chen, M.P.H., and Ying-An Chen, M.P.H. Volume 23, Number 3, 2009 AIDS PATIENT CARE and STDs

In 1984, soon after the first case of AIDS was reported, the Taiwan CDC as well as local health departments began to collect case reports of AIDS In this paper, we used national HIV/AIDS case surveillance data in Taiwan for the years 1990– 2005 to describe epidemiologic trends

Taiwan has a population of approximately 22.7 million The national Department of Health has passed legislation and written rules to mandate data collection on AIDS cases since 1990 Local health departments use active and passive surveillance methods to collect information on AIDS cases Collected information were entered in local databases and electronically forwarded to the Taiwan CDC

The Taiwan AIDS surveillance definition and its modification are modeled after the CDC, USA HIV – receive diagnosis of HIV AIDS - has AIDS when first received HIV diagnosis, or progress to having AIDS after reported with HIV infection people with AIDS Diagnosis year: the year of AIDS diagnosis number of people living with AIDS: total number of AIDS – deceased people with AIDS

HIV diagnosis Late - HIV diagnosis was within 3 months of AIDS diagnosis Early – HIV diagnosis more than 3 months prior to AIDS diagnosis clinically relevant periods Pre-HAART era – HAART era – excluded children younger than 13 years due to differences in transmission and disease progression patterns

IPR(t) – incidence-to-prevalence ratio R(t) – mean number of new infections originating per already-infected individual D – mean duration of infectiousness R(t) = IPR(t) * D R(t) > 1 → IPR(t) > T E T E – epidemic threshold = 1/D IPR(t) for year ‘‘y’’ – new (incident) diagnoses in year (y + d) / (prevalent) diagnosed and subsequently diagnosed infections at the end of the year (y - 1).

Relative to the group with HIV diagnosis, the protective survival effect associated with being in the HAART era was stronger for both groups Hazard ratio Early HIV (95% CI 0.36–0.54) Late HIV (95% CI 0.31–0.49) Relative to the group before and after HAART, no significant differences in the protective survival effect associated with being in the early or late HIV diagnosis groups

Important changes absolute number of HIV diagnoses has increased at a greater rate in the last 2 years The vast majority of HIV infections occurred among IDUs proportion of annual diagnoses that occurred in IDUs rose rapidly from 9% in 1990 to 72% in 2005 IPR(t) has exceeded epidemic threshold in recent years growing epidemic of AIDS among IDUs in Taiwan

Risk groups except for IDUs IPR on the decline, likely due to proportion of population falls increasing number of incident and prevalent infections, means increasing acquisition risk IDUs group IPR increased sharply and exceeded T E recently

Mandatory HIV screening has been initiated since 1984, when first HIV/AIDS diagnosed Data reflect the increasing rates of HIV transmission The spread of HIV among IDUs continues to rapidly increase Needle exchange programs are potentially a key for containing the HIV epidemic among drug users Current trends in mortality indicate the success of using HAART in persons living with HIV

The study used national surveillance data so the completeness of reporting is important. An estimate of the completeness of AIDS case reported in Taiwan is needed in the future AIDS case follow-ups with providers to identify exposure category may be incomplete Calculation of the IPR is misleading as we did not have data on incidence of HIV infection, only incidence of reporting of HIV status

The potential for an AIDS epidemic among IDUs in Taiwan will necessitate changes in AIDS prevention programs, which are currently predominantly oriented toward the homosexual Promoting the use of sterile needles by addicts unable to stop injection may be the most effective means of halting the spread of the AIDS epidemic