HIV and AIDS Trends

Nationwide, to determine where HIV is having the greatest public health impact, where its toll is increasing, and where it is stabilizing or decreasing, it is important to look at HIV as not one, but several epidemics. The dynamics of the HIV epidemic are different in various populations. Looking only at the big picture -- either the total number of AIDS cases or the total number of people estimated to be infected -- may mask the true impact of HIV disease on certain groups of individuals. In this document, CDC presents current data on the magnitude and direction of the epidemic nationally and identifies regional trends. CDC collects these data to help communities target and evaluate prevention efforts. State health departments can provide more detailed information about HIV and AIDS in local areas.

To develop the most complete analysis, CDC examines several data sources. This fact sheet uses three: (1) annual AIDS cases are used to analyze changes in the characteristics of people reported to CDC with AIDS over time; (2) estimated AIDS incidence (the number of people diagnosed with AIDS each year) is used to analyze trends over time*; and (3) statistical estimates and surveys of HIV prevalence (the total number of people infected with HIV) are used to provide an indication of who has become infected with HIV more recently and to predict future trends in HIV-related illness and death.

AIDS

Since the epidemic began, over 500,000 Americans have been reported with AIDS. At least 300,000 of them have died. In 1995, 74,180 people were reported with AIDS. Estimated AIDS incidence has increased at a rate of less than 5% each year since 1992. This percentage increase is much lower than earlier years in the epidemic. In the mid-'80s, AIDS incidence increased by 65 to 96% each year.

HIV

• The most recent estimate of HIV prevalence indicates that between 650,000 and 900,000 Americans are living with HIV. This estimate is derived from statistical techniques that have been refined and expanded since the 1990 Public Health Service (PHS) estimate of 800,000 to 1,200,000 people infected. Researchers now have additional years of data and more precise information on the completeness of AIDS reporting. The new estimate more accurately reflects the current state of knowledge.

• Statistical models suggest that at least 40,000 Americans are being infected with HIV each year. Because roughly the same number of people are dying each year from HIV-related illnesses, the estimated prevalence of HIV in the population (that is, the number of people living with HIV) has remained relatively stable in the United States since 1990.

• Stable HIV prevalence in recent years suggests that the overall growth in AIDS incidence, now at an annual rate of less than 5%, will continue to slow and may begin to decline in the near future.

Overall Trends

• Estimated AIDS incidence continues to increase overall. But the rate of increase varies by exposure category. Between 1993 and 1994, AIDS incidence increased 6% among men who have sex with men (MSM) and 5% among injecting drug users (IDUs).

• Estimated AIDS incidence is increasing most rapidly among those infected through heterosexual contact. Between 1993 and 1994, heterosexual AIDS incidence increased 17%.

• Estimated AIDS incidence continues to increase each year among men and women, but between 1993 and 1994, the rate of increase among men slowed to a 5% annual increase. Over the same period, the annual rate of increase among women was 10%.

• While AIDS incidence in women continues to increase, we have observed a slight decline in incidence in children who are born to HIV-infected mothers. This likely reflects, in part, successful prevention and treatment efforts.

• Estimated AIDS incidence among children under 13 declined by 11% from 1993 to 1994.

• Injecting drug use has played a significant role in the transmission of HIV to IDUs, their sex partners, and their children. In 1995, 35% of reported AIDS cases among men and women infected heterosexually were attributed to sex with an IDU, and 45% of children infected perinatally were born to women who were IDUs or sexual partners of IDUs.

• African Americans and Hispanics are disproportionately affected by the epidemic. Of all racial and ethnic groups, the rate of reported AIDS cases per 100,000 people in 1995 was highest among African Americans (92.6 per 100,000). The rate among Hispanics was 46.2 per 100,000; the rate among whites was 15.4 per 100,000; the rate among American Indian and Alaska Natives was 12.3 per 100,000; and the rate among Asian Pacific Islanders was 6.2 per 100,000.

• The proportion of AIDS cases among African Americans and Hispanics is increasing. In 1995, for the first time, the proportion of persons reported with AIDS who are African American was equal to the proportion who are white (40%). African Americans and Hispanics combined represented the majority of cases among men (54%) and women (76%).

Trends Among Young and Middle-Aged Adults and Among Adolescents

• HIV-related death has the greatest impact on young and middle-aged adults, particularly racial and ethnic minorities. HIV is the leading cause of death for Americans between the ages of 25 and 44.

• In 1994, 1 in every 3 deaths among young African American men between the ages of 25 and 44 was due to HIV-related illness. And 1 in every 5 deaths among young African American women between the ages of 25 and 44 was due to HIV-related illness.

• While there are few data on HIV prevalence and incidence among young people, estimates based on the age distribution of AIDS cases suggest that in recent years, as many as 1/2 of new HIV infections may be among people under the age of 25.

• Recent AIDS case reports provide an indication of how young people are becoming infected. Among young men (aged 13 to 24 years), 55% of reported AIDS cases in 1995 were among young MSM, 10% were among young men infected through injecting drug use, and 6% were among young men infected heterosexually.

• Among young women in the same age group, 51% of reported AIDS cases in 1995 were among young women infected heterosexually, and 17% were among young women infected through injecting drug use.

• The limited surveys of HIV infection in this age group suggest that prevalence may be stabilizing overall in this age group. With sustained, targeted prevention efforts for each group entering young adulthood, perhaps we can further reduce this toll.

• There are encouraging signs of possible decline in some subgroups of adolescents. A survey of HIV infection among 16-to 21-year-old youth entering the Job Corps, a training program for socially and economically disadvantaged youth, suggests relatively stable prevalence in recent years among young women in this subgroup of adolescents and declining prevalence among young men in this subgroup (prevalence declined from .36% in 1988 to .18% in 1994). Overall, prevalence was higher among African Americans (.41%) than among Hispanics (.14%) or whites (.08%).

These trends provide evidence that HIV prevention works. Efforts to date have resulted in behavior change among some groups, and the HIV epidemic has slowed overall. But a great deal more must be done. The number of new infections each year - at least 40,000 - is unacceptable. CDC provides these and other data to communities as a starting point to help evaluate and address their unique prevention needs. Because of multiple subepidemics of HIV, prevention programs are most effective when designed and implemented at a local level.

It is critical that effective prevention programs be sustained and that lessons learned in one area be applied to designing programs for groups and communities that have not yet been effectively reached. It is also clear that for prevention efforts to succeed, HIV prevention programs must continue to work with substance abuse prevention and treatment programs. Combating the duel epidemics of drug use and HIV will continue to present complex challenges. But many communities are seeing signs of success. And as long as we continue to see preventable infections occurring each year, we must work to do things better.

The Changing Landscape of the Epidemic: A Closer Look

Cumulatively, the largest proportion of AIDS cases has been reported among men who have sex with men (MSM). But an analysis of AIDS reporting over time reveals several shifts in the epidemic. Comparing the epidemic in 1985 to 1995, we can see the following trends.

By Exposure Category

The proportion of newly reported AIDS cases attributed to MSM decreased from 66% of the annual total in 1985 to 42% in 1995.

The proportion of newly reported AIDS cases among adults and adolescents attributed to injecting drug use increased from 17% in 1985 to 26% in 1995.

The proportion of newly reported AIDS cases among adults and adolescents infected heterosexually increased from 2% in 1985 to 11% in 1995.

By Gender

Women account for an increasing proportion of newly reported AIDS cases. The proportion of female adult and adolescent AIDS cases increased from 7% of the annual total in 1985 to 19% in 1995.

In contrast, the proportion of male adult and adolescent AIDS cases decreased from 93% of the annual total in 1985 to 81% in 1995.

By Region

Although the rate of AIDS cases reported per 100,000 people remains highest in the Northeast, the epidemic is spreading to other regions, with an increasing proportion of cases reported in the South.

Cases in the Northeast represent a decreasing proportion of the annual total, declining from 42% in 1985 to 31% in 1995.

The proportion of newly reported AIDS cases in the South increased from 24% in 1985 to 36% in 1995.

The proportion of cases in the West decreased from 28% in 1985 to 20% in 1995.

The proportion of newly reported AIDS cases in the North Central region increased from 6% in 1985 to 10% in 1995.

By Risk Category

• In 1995, 30,671 AIDS cases (42% of the year's total cases) were reported among MSM.

• Estimated AIDS incidence among MSM increased 6% from 1993 to 1994.

• While the proportion of AIDS cases related to MSM is declining overall, the proportion continues to increase among young MSM. Among male adolescents (aged 13-19 years) with AIDS, the proportion related to MSM increased from 29% in 1994 to 34% in 1995.

• When AIDS emerged in the early 1980s, prevention programs were first targeted to those hardest hit -- MSM in New York City, Los Angeles, and San Francisco. Due in part to sustained prevention efforts, the rate of new AIDS diagnoses among gay and bisexual men has decreased dramatically among white men in these cities -- with rates declining by 20% in New York City, 16% in Los Angeles, and 3% in San Francisco between 1989 and 1994.

• However, in these same cities, the rate of new AIDS diagnoses among African American MSM increased dramatically during this period -- with rates increasing by 49% in New York City, 48% in Los Angeles, and 53% in San Francisco.

• Recent studies show that both HIV prevalence and risk behaviors remain high among young MSM. In a sample of young MSM (aged 15-22) in 6 urban counties, researchers found that between 5% and 9% were infected with HIV. A higher percentage of blacks (8-13%) and Hispanics (5-9%) were infected than whites (4-6%).

By Race or Ethnicity

African Americans account for an increasing proportion of yearly reported cases -- from 25% in 1985 to 40% in 1995.

Similarly, the proportion of newly reported cases among Hispanics has steadily increased from 15% of the annual total in 1985 to 19% in 1995.

In contrast, the proportion of cases among whites has decreased from 60% in 1985 to 40% in 1995.

Note: The proportion of cases among Asians and American Indians has remained at less than 1%.

Men Who Have Sex With Men (MSM)

To date, HIV-related illness and death have had the greatest impact on MSM. And MSM continue to account for the largest number of AIDS cases reported annually. But the rate of increase in AIDS incidence in MSM has slowed overall. The overall stabilization among MSM reflects declines in some groups of MSM -- most notably older white men -- but increases in others. Data suggest that the highest rate of new infection is among minority MSM. These findings emphasize that prevention is not a "one-shot deal." Sustained, targeted prevention efforts will be needed to reduce the stable -- but still high -- rate of AIDS cases among MSM.

• In 1995, 30,671 AIDS cases (42% of the year's total cases) were reported among MSM.

• Estimated AIDS incidence among MSM increased 6% from 1993 to 1994.

• While the proportion of AIDS cases related to MSM is declining overall, the proportion continues to increase among young MSM. Among male adolescents (aged 13-19 years) with AIDS, the proportion related to MSM increased from 29% in 1994 to 34% in 1995.

• When AIDS emerged in the early 1980s, prevention programs were first targeted to those hardest hit -- MSM in New York City, Los Angeles, and San Francisco. Due in part to sustained prevention efforts, the rate of new AIDS diagnoses among gay and bisexual men has decreased dramatically among white men in these cities -- with rates declining by 20% in New York City, 16% in Los Angeles, and 3% in San Francisco between 1989 and 1994.

• However, in these same cities, the rate of new AIDS diagnoses among African American MSM increased dramatically during this period -- with rates increasing by 49% in New York City, 48% in Los Angeles, and 53% in San Francisco.

• Recent studies show that both HIV prevalence and risk behaviors remain high among young MSM. In a sample of young MSM (aged 15-22) in 6 urban counties, researchers found that between 5% and 9% were infected with HIV. A higher percentage of blacks (8-13%) and Hispanics (5-9%) were infected than whites (4-6%).

• A national survey of HIV prevalence among clients entering public STD clinics suggests that the overall declines in AIDS cases among MSM will continue but reinforces the need to reach African American MSM with prevention programs. HIV prevalence in this survey declined between 1988 and 1993, but the declines among young black MSM were not as great as those among young white and Hispanic MSM.+

• And, although prevalence declined overall among MSM in this survey, it remains very high. In half of the STD clinics surveyed, more than 25% of MSM were infected with HIV.+

Injecting Drug Use

AIDS cases diagnosed among injecting drug users (IDUs) increased rapidly during the early 1990s, but annual increases have slowed since 1993. HIV prevalence data suggest that the rate of infection among IDUs has stabilized at a high rate -- with the highest concentration of infections remaining in the Northeast. AIDS cases and new infections related to injecting drug use appear to be increasingly concentrated in minorities, particularly African Americans.

• In 1995, 19,261 AIDS cases (26% of the year's total cases) were reported among IDUs.

• Estimated AIDS incidence related to injecting drug use increased 5% from 1993 to 1994.

• By region, the Northeast accounted for 50% of adult and adolescent AIDS cases reported among IDUs in 1995, followed by the South (27%), and the West (10%).

• HIV prevalence among IDUs entering drug treatment through 1993 was also highest in the Northeast, suggesting that the majority of injecting drug use AIDS cases will continue to be reported from that area.

• HIV prevalence from 1988 through 1993 among IDUs entering drug treatment across the nation generally remained the same. In half of the drug treatment centers surveyed, more than 7.5% of IDUs entering treatment were infected.

Heterosexual Contact

Estimated AIDS incidence is increasing more rapidly among heterosexuals than among MSM and IDUs. Consequently, the proportion of yearly reported AIDS cases related to heterosexual sex has increased steadily over time, from 2% in 1985 to 11% in 1995.

• Estimated AIDS incidence among people infected heterosexually increased 17% from 1993 to 1994.

• Of 8,093 heterosexual AIDS cases reported in 1995, 5,253 (65%) were among women. Of these cases, 37% were sex partners of IDUs. Of the remaining cases, 54% were sex partners of HIV-infected people whose risk was not specified,++ 7% were sex partners of bisexual men, 1% were sex partners of people with hemophilia, and 1% were sex partners of transfusion recipients.

• In 1995, 2,840 men reported with AIDS were infected through heterosexual contact. Of these cases, 33% were sex partners of IDUs. Of the remaining cases, 65% were sex partners of HIV-infected people whose risk was not specified, 2% were sex partners of transfusion recipients, and fewer than 1% were sex partners of people with hemophilia.

• In comparing the first 6 months of 1995 with the first 6 months of 1994, estimated AIDS incidence among women who were heterosexual sex partners of IDUs increased 9%. Estimated AIDS incidence among men who were heterosexual sex partners of IDUs increased 17%. Injecting drug use continues to play a major role in the heterosexual spread of AIDS.

• HIV prevalence among childbearing women has been relatively stable since 1989. This suggests that AIDS cases among women may begin to slow over the next few years.

• However, this decrease may reflect changes in childbearing among women who are HIV infected. Additionally, these data do not distinguish between women infected through heterosexual contact and those infected through injecting drug use. If infections caused by injecting drug use have decreased among childbearing women, heterosexual infections in this group may have increased.