Disease Control and Prevention (CDC) collects, analyzes, and disseminates surveillance data on diagnoses of HIV infection; these data are the national source of information on HIV in the United States. The data presented are estimated numbers and rates and are based on the date of diagnosis of HIV infection and infection classified as stage 3 (AIDS) (diagnosed through December 31, 2014; reported as of Aug 31, 2015). Estimated numbers resulted from statistical adjustment that accounted for reporting delays and missing transmission category (where appropriate), but not for incomplete reporting. For the assessment of trends in diagnoses, deaths, or prevalence, it is preferable to use statistically adjusted (estimated) data to eliminate artifacts of reporting in the surveillance system. Rates and trends based on estimated numbers less than 12 should be interpreted with caution because the estimates have relative standard errors greater than 30% and are considered unreliable. In addition, county level data should be interpreted with caution, as numbers for some counties may reflect current or past prison populations.
Surveillance of HIV Infection:
As of April 2008, 57 areas (50 states, the District of Columbia, and 6 U.S. dependent areas) had implemented confidential name-based HIV infection reporting. The Atlas includes data from case reports from 56 areas (50 states, the District of Columbia, American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the U.S. Virgin Islands) in which laws or regulations require confidential reporting by name for adults and adolescents with confirmed diagnoses of HIV infection (including stage 3 (AIDS)) as of December 31, 2014. Data for the Republic of Palau are not currently included in the Atlas. After the removal of personal identifying information, data from these reports were submitted to CDC. Although AIDS cases have been reported to CDC since 1981, the implementation of HIV infection reporting has differed from state to state. All states, the District of Columbia, and 6 U.S. dependent areas had fully implemented name-based HIV infection reporting by April 2008. Data on diagnoses of HIV infection should be interpreted with caution. Data may not be representative of all persons with HIV because not all infected persons have been tested. Also, many states offer anonymous testing; the results of anonymous tests are not reported to the confidential name-based HIV registries of state and local health departments. The data presented in the Atlas provide minimum estimates of persons for whom HIV infection has been diagnosed and reported to the national HIV surveillance system. In addition, because surveillance practices differ, the reporting and the updating of a person‚Äôs clinical and vital status differ among states. The completeness of reporting of HIV diagnoses is estimated at more than 80. Due to the confidentiality of the HIV diagnosis reporting and the differences in surveillance practices, there is a minimum estimate provided of persons diagnosed with the infection. The death rates are also provided.
Persons reported to the national HIV surveillance system are assumed alive unless their deaths have been reported to CDC by state/local HIV surveillance programs. Death data include deaths of persons with diagnosed HIV infection or with infection classified as stage 3 (AIDS) regardless of the cause of death. Because of delays in the reporting of deaths, death data are displayed only through 2013 (HIV infection: 2008 -2013; stage 3 (AIDS): 2000-2013). The exclusion of data for the most recent year allowed at least 18 months for deaths to be reported to CDC. The estimated numbers and rates of deaths resulted from statistical adjustment for delays in reporting.
Persons Living with a Diagnosed HIV Infection or infection classified as stage 3 (AIDS)
Because of delays in the reporting of deaths, prevalence data are only displayed through 2013. The data reflect persons living with diagnosed HIV infection at the end of each year during 2008-2013, or persons living with infection ever classified as stage 3 (AIDS) at the end of each year during 2000-2013. The exclusion of data for the most recent year allowed at least 18 months for deaths to be reported to CDC and for these deaths to be factored into prevalence calculations.
Diagnoses: Diagnoses of HIV infection or infection classified as stage 3 (AIDS) refer to confirmed diagnoses during a given time period. For example, the 2014 data on HIV infection would include persons with laboratory-confirmatory evidence of HIV infection during January 1, 2014 through December 31, 2014 and reported to CDC through July 31, 2015.
Current data re-release agreements between CDC and state/local HIV surveillance programs require certain levels of cell suppression at the state and county level in order to ensure confidentiality of personal identifying information.
A data suppression rule is applied to 1-way and 2-way demographic/transmission category data where the population denominator is less than 100. In addition, data are suppressed or aggregated to preclude arithmetic calculation of a suppressed cell: two-way demographic/transmission category stratifications for dependent areas (except Puerto Rico, for age and sex), as well as the race groups Native Hawaiians or other Pacific Islanders (NHOPIs) and Multiple races, are not displayed. Two-way demographic/transmission category stratifications are not shown for New Hampshire.
In addition to adhering to the county-level data suppression requirements of the data re-release agreements for each state, additional data suppression rules were applied. For county totals, a data suppression rule was applied where the population denominator is less than 100 or total case count less than 5. Additional suppression rules were applied to 1-way demographic/transmission category data to preclude arithmetic calculation of a suppressed cell. National data displayed in the Atlas may not be comparable to surveillance data published by individual jurisdictions. This is because: (1) CDC de-duplicates cases at the national level, and (2) national data are statistically adjusted for reporting delays and missing transmission category, but not for incomplete reporting.
As mentioned above, the Atlas only includes data for adults and adolescents (i.e., persons aged 13 and older). When comparing HIV data with STD and/or TB data, the HIV age group remains ages 13-24.
In 1997, the Office of Management and Budget (OMB) announced the revisions to the classification of federal data on race and ethnicity. Starting with 2003, the HIV surveillance data presented utilize this new classification standard and the following racial/ethnic categories: American Indian or Alaska Native, Asian, black or African American, Hispanic or Latino, Native Hawaiian or Other Pacific Islander, white and multiple races. (As that format was not available for data collected prior to 2003, data are not displayed for the years 2000 through 2002 for the race categories Asian, Native Hawaiian and other Pacific Islander, and multiple races). For data on persons living with HIV infection or persons living with infection ever classified as stage 3 (AIDS), the Asian category includes Asian/Pacific Islander legacy cases (cases that were diagnosed and reported under the pre-1997 OMB race/ethnicity classification system). Persons of Hispanic/Latino ethnicity can be of any race
Transmission category is the term for the classification of cases that summarizes a person‚Äôs possible HIV risk factors; the summary classification results from selecting, from the presumed hierarchical order of probability, the one risk factor most likely to have resulted in HIV transmission. The exception is men who had sexual contact with other men and injected drugs; this group makes up a separate transmission category. Persons whose transmission category is classified as male-to-male sexual contact include men who report sexual contact with other men (i.e., homosexual contact) and men who report sexual contact with both men and women (i.e., bisexual contact). Persons whose transmission category is classified as injection drug use (IDU) are persons who injected non-prescribed drugs. Persons whose transmission category is classified as heterosexual contact are persons who have ever had specific heterosexual contact with a person known to have, or to be at high risk for, HIV infection (e.g., an injection drug user). All other transmission categories have been collapsed –other- into transmission category includes: hemophilia, blood transfusion, perinatal exposure, and risk factor not reported or not identified
Rates per 100,000 population were calculated for (1) the numbers of diagnoses of HIV infection and the numbers of infections classified as stage 3 (AIDS), (2) the numbers of deaths of persons with diagnosed HIV infection and deaths of persons with infection classified as stage 3 (AIDS), and (3) the numbers of persons living with diagnosed HIV infection and persons living with infection classified as stage 3 (AIDS).The population denominators used to compute the rates for the 50 states, the District of Columbia, and Puerto Rico were based on the Vintage 2009 postcensal estimates file (for the years 2000 to 2009) and the Vintage 2014 file (for years 2010 to 2014) from the U.S. Census Bureau. The population denominators for American Samoa, Guam, the Northern Mariana Islands, and the U.S. Virgin Islands were based on estimates and projections from the U.S. Census Bureau‚Äôs International Data Base. Each rate was calculated by dividing the estimated total number of diagnoses (or deaths or prevalence) for the calendar year by the population for that calendar year and then multiplying the result by 100,000. The denominators used for calculating age-, sex-, and race/ethnicity-specific rates were computed by applying the appropriate vintage estimates for age, sex, and race/ethnicity for the 50 states and the District of Columbia. The same method was used to calculate the denominators for Puerto Rico, with the exception of race/ethnicity estimates; these data are not available for Puerto Rico. Because of lack of data from the U.S. Census Bureau and small cell sizes, subpopulation rates by age, sex, and race/ethnicity are not calculated for the dependent areas (except Puerto Rico). Similarly, rates for transmission categories are not provided because of the absence of denominator data (i.e., the denominator data used in this report come from the U.S. Census Bureau, but the bureau does not collect data on transmission categories.
Description source: Centers for disease control and prevention, C.D.C. (2016). Cdc.gov. Retrieved 24 September, 2016.