Wealthy nations called on to boost support efforts. Five-year plan estimated to cost $9.2 billion.

Using the 20-year mark in the history of AIDS as a catalyst, the United Nations and other international organizations have called upon the world's wealthier nations to increase attention, support, and funding to HIV/AIDS prevention and treatment efforts. This call to action included a series of meetings with business and political leaders and culminated in the first United Nations General Assembly Special Session on HIV/AIDS, held in June.

Epidemiological analysis of the quality of HIV sero-surveillance in the world: how well do we track the epidemic?

OBJECTIVE: The objective of this paper was to analyse the quality of HIV/AIDS sentinel surveillance systems in countries and the resulting quality of the data used to make estimates of HIV/AIDS prevalence and mortality. METHODS: Available data on sero-surveillance of HIV/AIDS in countries were compiled in the process of making the end of 1999 estimates of HIV/AIDS. These data came primarily from the HIV/AIDS Surveillance Database developed by the United States Census Bureau, from a database maintained by the European Centre for the Epidemiological Monitoring of AIDS and all country reports on sentinel surveillance that had been provided to World Health Organization or UNAIDS. Procedures were developed to score quality of surveillance systems based on four dimensions of quality: timeliness and frequency; appropriateness of groups; consistency of sites over time; and coverage provided by the system. In total, the surveillance systems from 167 countries were analysed. RESULTS: Forty-seven of the 167 countries whose surveillance systems were rated were judged to have fully implemented sentinel surveillance systems; 51 were judged to have systems that had some or most aspects of a good HIV surveillance system in place and 69 were rated as having poorly functioning or non-existent surveillance systems. CONCLUSION: This analysis suggests that the quality of HIV surveillance varies considerably. The majority of countries most affected by HIV/AIDS have systems that are providing sufficient sero-prevalence data for tracking the epidemic and making reasonable estimates of HIV prevalence. However, many countries have poor systems and strengthening these is an urgent priority.

The global impact of HIV/AIDS.

The scale of the human immunodeficiency virus (HIV)/AIDS epidemic has exceeded all expectations since its identification 20 years ago. Globally, an estimated 36 million people are currently living with HIV, and some 20 million people have already died, with the worst of the epidemic centred on sub-Saharan Africa. But just as the spread of HIV has been greater than predicted, so too has been its impact on social capital, population structure and economic growth. Responding to AIDS on a scale commensurate with the epidemic is a global imperative, and the tools for an effective response are known. Nothing less than a sustained social mobilization is necessary to combat one of the most serious crises facing human development.

The effectiveness of HIV prevention and the epidemiological context.

Planning an intervention to prevent infections with the human immunodeficiency virus (HIV) should be guided by local epidemiological and socioeconomic conditions. The socioeconomic setting and existing public service capacity determine whether an intervention can have a significant outcome in terms of a reduction in a defined risk. The epidemiological context determines whether such risk reduction translates into a measurable impact on HIV incidence. Measurement of variables describing the epidemiological context can be used to determine the local suitability of interventions, thereby guiding planners and policy-makers in their choice of intervention. Such measurements also permit the retrospective analysis of the impact of interventions where HIV incidence was not recorded. The epidemiological context is defined for four different categories of intervention, shown to be effective in lower-income countries by randomized controlled trials. Appropriate indicators for the epidemiological context and methodological guidelines for their measurement are proposed. Their use in the transfer of a successful intervention from one context to another and in scaling up the effort to control HIV infection is explored. These indicators should provide a useful resource for those involved in planning HIV prevention interventions.

AIDS in a new millennium.

As we enter the new millennium the world is still facing the challenge of responding to the AIDS pandemic. A new report from the Joint United Nations Programme on HIV/AIDS presents the latest statistics on prevalence, spread, and impact of the disease. In their Perspective, Schwartländer and his colleagues discuss the newly released statistics and the strategies needed to combat the further spread of HIV/AIDS and to reduce prevalence in the most severely affected countries.

Country-specific estimates and models of HIV and AIDS: methods and limitations.

OBJECTIVE: This paper presents the methods used to calculate the end of 1997 country-specific estimates of HIV and AIDS produced by the UNAIDS/WHO Working Group on Global HIV/AIDS and STD Surveillance. The objective of this exercise was to improve estimates on HIV/AIDS by using country-specific models of HIV/AIDS epidemics. The paper describes and discusses the processes and obstacles that were encountered in this multi-partner collaboration including national and international experts. METHODS: The 1997 estimates required two basic steps. First, point prevalence estimates for 1994 and 1997 were carried out and the starting year of the epidemic was determined for each country. The procedures used to calculate the estimates of prevalence differed according to the assumed type of the epidemic and the available data. The second step involved using these estimates of prevalence over time and the starting date of the epidemic to determine the epidemic curve that best described the spread of HIV in each particular country. A simple epidemiological program (EPIMODEL) was used for the calculation of estimates on incidence and mortality from this epidemic curve. RESULTS: Regional models that were used in previous estimation exercises were not able to capture the diversity of HIV epidemics between countries and regions. The result of this first country-specific estimation process yielded higher estimates of HIV infection than previously thought likely, with over 30 million people estimated to be living with HIV/AIDS. The application of survival times that are specific to countries and regions also resulted in higher estimates of mortality, which more accurately describe the impact of the epidemics. At the end of 1997, it was estimated that 11.7 million people worldwide had died as a result of HIV/AIDS since the beginning of the epidemic. CONCLUSION: This exercise is an important step in improving understanding of the spread of HIV in different parts of the world. There are, however, shortcomings in the current systems of monitoring the epidemic. Improvements in HIV surveillance systems are needed in many parts of the world. In addition, further research is needed to understand fully the effects of the fertility reduction as a result of HIV, differing sex ratios in HIV infection and other factors influencing the course and measurement of the epidemic.

The HIV/AIDS epidemic in eastern Europe: recent patterns and trends and their implications for policy-making.

OBJECTIVE: To describe recent patterns and trends in the HIV epidemic in eastern Europe. METHODS: AIDS programme managers and epidemiologists of 23 countries were contacted and requested to provide national HIV surveillance data. Joint United Nations Programme on HIV/AIDS/World Health Organisation country fact sheets were reviewed and analysed, and this information was supplemented with published HIV prevalence and sexually transmitted disease case reporting information, unpublished travel reports and expert evaluations. RESULTS: The cumulative number of HIV cases reported in the region increased more than fivefold between 1995 and 1997, from 9111 to 46573; Ukraine, Russia and Belarus accounted for about 90% of all new cases. Dramatic increases in the number of HIV-infected injecting drug users (IDU) were reported from these countries, and a similar pattern was emerging in Moldova, the Baltic States, the Caucasus and Kazakstan. In central Europe, the increase in the number of cases was much lower, and (with the exception of Poland) homosexual transmission was most common, whereas in the Balkan countries, cases due to heterosexual transmission were reported relatively more frequently. At the end of 1997, more than 50% of all cases region-wide had been reported from IDU. HIV prevalence data were inconclusive. The number of reported syphilis cases had risen significantly in the countries of the former Soviet Union. CONCLUSION: Our data confirm that HIV must have been rapidly spreading among IDU in several countries of the former Soviet Union, whereas central and southeast Europe have so far escaped a more extensive spread of HIV. Factors that might have fuelled a massive spread among IDU include changes in drug demand and supply, migration and specific local drug production and consumption patterns. High rates of syphilis reported in the countries of the former Soviet Union highlight that subregion's increased vulnerability with regards to a further spread of the epidemic, via heterosexual intercourse, into the general population.

Anonymous unlinked testing as a sentinel approach: experience in Germany.

STUDY OBJECTIVE: To establish a laboratory sentinel as a supplementary instrument for monitoring the seroprevalence of HIV among childbearing women as a proxy to the heterosexually active population. DESIGN/SETTING: Anonymous unlinked testing of neonatal dried blood spots has been performed in central laboratories of three federal states since 1993. The survey uses residual dried blood spots collected on Guthrie cards for screening of infants for metabolic disorders. These are eluted and tested for HIV antibodies. Data retained with the specimen are only district of residence along with year and month of birth. PARTICIPANTS: Because maternal IgG crosses the placenta before birth, the presence of antibodies in newborns reflects the infection status of the mother. Childbearing women are fairly representative for the heterosexually active general population. MAIN RESULTS: The observed HIV prevalence in childbearing women of less than 1 per thousand confirms the assumption of a low rate of HIV infection in the general population. Significant time trends could not be detected, but HIV prevalence was higher in metropolitan compared with rural areas. CONCLUSIONS: Laboratory sentinels in general and the anonymous unlinked testing of neonatal dried blood spots in particular can supply additional information on HIV seroprevalence. This surveillance system could be expanded to utilise residual samples of other sources as well as to monitor the immunity against specific vaccine preventable diseases and other infectious diseases of public health relevance.

An outbreak of sheep-associated Q fever in a rural community in Germany.

In spring 1996, an outbreak of Q fever occurred among residents of a rural town (population: 300) in Germany. A retrospective cohort study was conducted to ascertain the extent of the outbreak and to assess potential risk factors for illness. In July 1996, all residents > or =15 years received a self-administered questionnaire and were offered Coxiella burnetii antibody testing. Residents were considered to have probable Q fever if they had a positive result for IgM C. burnetii antibodies by ELISA or possible Q fever if they had fever > or =39 degrees C lasting >2 days and > or =3 symptoms (chills, sweats, severe headache, cough, aching muscles/joints, back pain, fatigue, or feeling ill) after 1 January 1996. Two hundred (84%) of the 239 residents aged > or =15 years either completed the questionnaire or submitted blood for antibody testing. Forty-five (23%) of these 200 met the probable or possible case definitions. Onsets of illness occurred in January-June 1996. Cases were geographically distributed throughout the town. Persons reporting contact with sheep (32% vs 18%, RR: 1.8, 95% CI: 1.1-2.9) and walking near a large sheep farm located next the town (34% vs 8%, RR: 4.5, 95% CI: 1.7-12.2) were more likely to have met the case definition than those without these exposures. Fifteen of 20 samples from the large sheep flock were positive for C. burnetii antibodies. The sheep had lambed outdoors in December 1995-January 1996 while the weather was extremely dry. The timing of the outbreak after lambing, the uniform distribution of cases throughout the town and the absence of risk factors among most case-persons suggest airborne transmission of C. burnetii from the large sheep farm.

Outbreak of Q fever in Lohra-Rollshausen, Germany, spring 1996.

Q fever is an acute (and sometimes chronic) febrile illness caused by the rickettsial organism Coxiella burnetii. The commonest animal reservoirs for C. burnetiiare cattle, sheep, and goats. Infected animals shed the organisms, which resist desiccation, i