Military Applicants

Since October 1985, all persons applying for active duty or reserve military service, the service academies, or the Reserve Officer Training Corps have been screened for HIV infection as part of the entrance medical evaluation. After removing all personal identifiers, the Department of Defense provides quarterly HIV screening results and information on sex, race/ethnicity, and age to CDC for surveillance purposes. No information is available on behavioral risk factors for HIV infection. All military applicants must have high school diplomas or the equivalent. Because of the large number of male and female applicants from all areas of the country, this population provides valuable information about the HIV epidemic, particularly among segments of the population in groups other than those at recognized high risk.

In the past, military applicants were informed by recruiting officials that drug use and homosexual activity were grounds for exclusion from the military. However, a new policy by which applicants would not be asked about homosexual activity was implemented in July 1993. Military applicants who test positive for HIV infection are informed of their test results and counseled by a physician. HIV-positive applicants are excluded from military service.

Prevalence rates were standardized to the 1993 population of military applicants by region, sex, race/ethnicity (black, Hispanic, white, American Indian/Alaska Native, Asian/Pacific Islander), age group (16–19, 20–24, 25–34, and ≥35 years), and MSA. For the 1993–1997 survey period, 1,714,215 specimens from military applicants were tested for HIV antibody. Most of the military applicants were whites (68%), followed by blacks (19%), Hispanics (9%), Asians/Pacific Islanders (2%), American Indians/Alaska Natives (1%), and unreported (1%). The applicant’s reported home state is the basis for the state-specific rates (Figure 24).

Figure 24. HIV Prevalence Among Military Applicants, by State of Residence, 1993–1997

Source of data: U.S. Department of Defense.

Overall unadjusted HIV prevalence for military applicants was 0.17% among blacks, 0.04% among Hispanics, 0.02% among whites, and 0.01% among American Indians/Alaska Natives and Asians/Pacific Islanders (Figure 25).

Figure 25. HIV Prevalence Among Military Applicants, by Race/Ethnicity, 1993–1997

Source of data: U.S. Department of Defense.

Although estimated HIV prevalence was low among military applicants in all regions, rates were consistently higher in the Northeast and the South than in the West and the Midwest. In the Northeast, rates increased from 0.05% in 1993 to 0.07% in 1995 before decreasing to 0.04% in 1997. Rates decreased in the other regions from 1993 to 1997: 0.06% to 0.04% in the South, 0.05% to 0.03% in the West, and 0.03% to 0.01% in the Midwest (Figure 26).

Figure 26. HIV Prevalence Among Military Applicants, by Region, 1993–1997

Note: Standardized to 1993 population of Job Corps entrants by sex, race/ethnicity, age group, and metropolitan statistical area.
Source of data: U.S. Department of Defense.

For male military applicants, overall prevalence was 0.05% in 1993, remained stable at 0.04% from 1994 through 1996, and then decreased to 0.03% in 1997. For women, prevalence increased from 0.04% in 1993 to 0.05% in 1994 before decreasing to 0.02% in 1997 (Figure 27).

Figure 27. HIV Prevalence Among Military Applicants, by Sex, 1993–1997

Note: Standardized to 1993 population of Job Corps entrants by region, race/ethnicity, age group, and metropolitan statistical area.
Source of data: U.S. Department of Defense.

Although there were downward trends during the survey period for male and female black military applicants, prevalence rates were markedly higher among black applicants of both sexes than among those who were Hispanic or white. Prevalence decreased among black men from 0.20% in 1993 to 0.13% in 1997 and among black women from 0.12% in 1993 to 0.05% in 1997 (Figures 28 and 29).

Figure 28. HIV Prevalence Among Male Military Applicants, by Race/Ethnicity, 1993–1997

Note: Standardized to 1993 population of Job Corps entrants by region, age group, and metropolitan statistical area.
Source of data: U.S. Department of Defense.

Figure 29. HIV Prevalence Among Female Military Applicants, by Race/Ethnicity, 1993–1997

Note: Standardized to 1993 population of Job Corps entrants by region, age group, and metropolitan statistical area.

Prevalence rates among male military applicants who were at least 25 years of age were consistently higher than among those who were younger. However, prevalence declined between 1993 and 1997 from 0.22% to 0.11% among male applicants who were 25–34 years and from 0.21% to 0.15% among those who were 35 years of age or older. Rates among male applicants who were 20–24 years old decreased from 0.06% in 1993 to 0.03% in 1997. Among the youngest age group (16–19 years) rates were stable at 0.02% or less (Figure 30).

Figure 30. HIV Prevalence Among Male Military Applicants, by Age Group, 1993–1997

Note: Standardized to 1993 population of Job Corps entrants by region, race/ethnicity, and metropolitan statistical area.
Source of data: U.S. Department of Defense.

Overall prevalence was very low among female military applicants. During 1993–1997, rates among those who were 25–34 years of age ranged from 0.03% to 0.11%. For female applicants who were 20–24 years of age, rates increased slightly between 1993 (0.05%) and 1995 (0.07%) before decreasing to 0.02% in 1997. For the youngest group of women (16–19 years) rates decreased from 0.04% in 1993 to 0.01% in 1997 (Figure 31). Data for women who were 35 years of age or older are not presented because of small numbers.

Figure 31. HIV Prevalence Among Female Military Applicants, by Age Group, 1993–1997

Note: Standardized to 1993 population of Job Corps entrants by region, race/ethnicity, and metropolitan statistical area. Data for women >=35 years of age excluded because of small numbers.
Source of data: U.S. Department of Defense.

Because applicants who are HIV-positive or who use drugs are not accepted into the military, self-selection bias among persons in high-risk categories is likely. Therefore, MSM, IDUs, and others who were aware or suspected that they were infected with HIV are likely to be under-represented in the population of military applicants.

Blood Donors

The prevalence of HIV infection in the highly selected population of blood and plasma donors is presumably lower than in the general population because of the policy of actively discouraging donations from persons at increased risk. In an attempt to reduce donations from persons at high risk for HIV infection, verbal screening of prospective donors for HIV risk factors and the request that persons with such risk factors refrain from donating began in 1983. Since early 1985, blood centers have screened all donated units for HIV. HIV-infected units are eliminated from the donor pool, and blood centers decline future donations from persons whose earlier donations tested positive for HIV infection. In a further attempt to ensure a safe blood supply, testing procedures for HIV and other blood-borne infections have been progressively strengthened and now include testing for HIV-1 and HIV-2 antibodies, as well as for HIV-1 p24 antigens.

Approximately 8 million people voluntarily donate 14 million units of blood (including approximately 700,000 autologous units) annually in the United States. HIV prevalence trends can best be determined from first-time blood donors, who represent approximately 20% of all donations. Since 1985, the American Red Cross, which collects approximately half of the voluntary donations in the United States, has provided CDC with routine HIV screening results for their blood donations.

Although prevalence was very low among first-time American Red Cross blood donors, rates were higher among men than among women. After a slight increase from 1993 to 1994 among men, prevalence then decreased from 0.032% in 1994 to 0.021% in 1997. Among women, prevalence was relatively stable (0.010% to 0.014%) during the 5-year period (Figure 32).

Figure 32. HIV Prevalence Among American Red Cross First-Time Blood Donors, by Sex, 1993–1997

Source of data: American Red Cross.

The policy of discouraging donations from persons at risk for HIV infection through high-risk sexual or drug behaviors means that a significant increase in the number of HIV-infected blood donations could indicate a new or emerging pattern of HIV transmission. Blood collection agencies have progressively strengthened their exclusion procedures for potential donors at increased risk for HIV infection. Also, as the availability of HIV counseling and testing has increased, more at-risk persons have learned their HIV infection status, reducing the likelihood that infected persons would donate. Thus, the declining HIV prevalence among first-time blood donors may not reflect the underlying HIV infection trends in the population at large.

Go to Interpretation and Discussion of Findings