Date: Fri, 16 Feb 1996 11:12:51 +0500 From: ghmcleaf{CONTRACTOR/ASPEN/ghmcleaf}%NAC-GATEWAY.ASPEN@ace.aspensys.com Subject: MMWR 02/16/96 MORBIDITY AND MORTALITY WEEKLY REPORT ****************************************** Centers for Disease Control and Prevention February 16, 1996 Vol. 45, No. 6 Articles included: * Update: Mortality Attributable to HIV Infection Among Persons Aged 25--44 Years --- United States, 1994 * Update: Influenza Activity --- United States, 1995--96 Season Update: Mortality Attributable to HIV Infection Among Persons Aged 25-44 Years -- United States, 1994 During the 1980s, human immunodeficiency virus (HIV) infection, the cause of acquired immunodeficiency syndrome (AIDS), emerged as a leading cause of death in the United States (1). In 1993, HIV infection became the most common cause of death among persons aged 25-44 years. This report updates national trends in deaths caused by HIV infection in 1994, which continue to increase.* Provisional estimates of deaths in 1993 and 1994 were based on a 10% sample of death certificates of U.S. residents filed in all 50 states and the District of Columbia (2,3). Demographic data were reported by funeral directors, and causes of death were reported by physicians, medical examiners, or coroners and encoded according to the International Classification of Diseases, Ninth Revision. Underlying causes of death were classified into the categories in CDC's "List of 72 Selected Causes of Death" for ranking (2). Rates were calculated using midyear U.S. population estimates based on decennial census data compiled by the U.S. Bureau of the Census. Information on Hispanic ethnicity and races other than white and black was unavailable in the provisional mortality data; each race includes Hispanics. In 1994, an estimated 41,930 U.S. residents died from HIV infection, a 9% increase over the estimated 38,500 in 1993; of these, 3% were aged less than 25 years; 72%, 25-44 years; and 25%, greater than or equal to 45 years. HIV infection was the eighth leading cause of death overall, accounting for 2% of all deaths. Among persons aged 25-44 years, HIV infection was the leading cause of death and accounted for 19% of deaths in this age group. In 1994, HIV infection became the fourth leading cause of years of potential life lost before age 65 (YPLL-65) (compared with fifth in 1993), accounting for 9% of YPLL-65 from all causes. Among men aged 25-44 years, HIV infection was the leading cause of death for all men (23% of deaths) (Figure 1) and for white and black men (20% and 32% of deaths, respectively). HIV infection was the third leading cause of death for all women in this age group (11% of deaths) (Figure 2), the fifth leading cause for white women (6% of deaths), and the leading cause for black women (22% of deaths). In 1994, the death rate from HIV infection per 100,000 population among persons aged 25-44 years was almost four times as high for black men (177.9) as for white men (47.2) and nine times as high for black women (51.2) as for white women (5.7). Compared with 1993, the rate for white men in 1994 was similar (47.5 and 47.2, respectively), and rates for the three other sex-racial groups continued to increase: the percentage increase was 13% for black men, 28% for black women, and 30% for white women (Figure 3). Reported by: Surveillance Br, Div of HIV/AIDS Prevention, National Center for Prevention Svcs; Mortality Statistics Br, Div of Vital Statistics, National Center for Health Statistics, CDC. Editorial Note: This analysis of provisional mortality data for 1993 and 1994 indicates a continuing increase in HIV infection as a leading cause of death in the United States, particularly among persons aged 25-44 years. Among persons in this age group, HIV infection became the most common cause of death for black men in 1991, for all men (all racial/ethnic groups combined) in 1992, and for white men in 1994. HIV became the third leading cause of death among women in this age group in 1994. In addition, as reflected by YPLL-65, HIV infection has become a leading cause of premature mortality. Because this analysis was based on the underlying cause of death recorded on death certificates, the findings in this report probably underestimate the impact of HIV infection on mortality in the United States. Previous studies have indicated that, among persons aged 25-44 years, deaths for which HIV infection was designated the underlying cause represent approximately two thirds to three fourths of all deaths attributable to HIV infection (4,5). The estimated number of death certificates with any mention of HIV infection (i.e., underlying or nonunderlying cause) in 1994 was 48,000 (CDC, unpublished data, 1995), compared with the approximately 42,000 on which HIV was listed as an underlying cause. Based on survival analysis of cases reported to CDC through the AIDS surveillance system--which includes other sources in addition to data from death certificates--and the completeness of reporting of AIDS cases and of deaths, an estimated 55,000 to 60,000 persons with AIDS died in 1994 (CDC, unpublished data, 1995). Trends in HIV-related mortality reflect changes in the demographic patterns of the HIV epidemic. For example, from 1993 to 1994, the death rate for HIV infection for white men aged 25-44 years did not change, and rates for women and black men increased; in 1994, the rate for black women aged 25-44 years surpassed that for white men in that age group. The increasing death rate for women affects the care of their children: the estimated 80,000 HIV-infected women of childbearing age who were alive in 1992 will leave approximately 125,000 to 150,000 children when they die during the 1990s (6). Racial differences in death rates for HIV infection probably reflect social, economic, behavioral, and other factors associated with HIV transmission risks. Such factors are being addressed through prevention efforts designed to meet the needs of specific communities (7). Because of the prolonged period from initial HIV infection to onset of severe HIV disease (AIDS) (8), recent trends in HIV-related mortality reflect trends in HIV transmission several years earlier. Similarly, trends in HIV-related mortality in several years will indicate, in part, the effectiveness of current efforts to prevent HIV infection. Despite recent increases in HIV-related mortality, decreases in the percentages of HIV-related deaths resulting from particular opportunistic infections (pneumocystosis, cryptococcosis, and candidiasis) (9) suggest some success in the treatment and prevention of opportunistic infections resulting from HIV infection and underscore the importance of following recently published guidelines for preventing HIV-related opportunistic infections (10). References 1. CDC. Update: mortality attributable to HIV infection among persons aged 25-44 years--United States, 1991 and 1992. MMWR 1993;42:869-72. 2. Singh GK, Mathews TJ, Kochanek K, et al. Annual summary of births, marriages, divorces, and deaths: United States, 1994. Hyattsville, Maryland: US Department of Health and Human Services, Public Health Service, CDC, 1995:18-32. (Monthly vital statistics report; vol 43, no. 13). 3. NCHS. Annual summary of births, marriages, divorces, and deaths: United States, 1993. Hyattsville, Maryland: US Department of Health and Human Services, Public Health Service, CDC, 1994:18-28. (Monthly vital statistics report; vol 42, no. 13). 4. Buehler JW, Devine OJ, Berkelman RL, Chevarley FM. Impact of the human immunodeficiency virus epidemic on mortality trends in young men, United States. Am J Public Health 1990;80:1080-6. 5. Buehler JW, Hanson DL, Chu SY. Reporting of HIV/AIDS deaths in women. Am J Public Health 1992;82:1500-5. 6. Caldwell MB, Fleming PL, Oxtoby MJ. Estimated number of AIDS orphans in the United States [Letter]. Pediatrics 1992;90:482. 7. Valdiserri RO, Aultman TV, Curran JW. Community planning: a national strategy to improve HIV prevention programs. J Community Health 1995;20:87-100. 8. Alcabes P, Munoz A, Vlahov D, Friedland G. Maturity of human immunodeficiency virus infection and incubation period of acquired immunodeficiency syndrome in injecting drug users. Ann Epidemiol 1994;4:17-26. 9. Selik RM, Chu SY, Ward JW. Trends in infectious diseases and cancers among persons dying from human immunodeficiency virus infection, United States, 1987-1992. Ann Intern Med 1995;123:933-6. 10. CDC. USPHS/IDSA guidelines for the prevention of opportunistic infections in persons infected with human immunodeficiency virus: a summary. MMWR 1995;44(no. RR-8). *Single copies of this report will be available until February 16, 1997, from the CDC National AIDS Clearinghouse, P.O. Box 6003, Rockville, MD 20849-6003; telephone (800) 458-5231 or (301) 217-0023. Update: Influenza Activity -- United States, 1995-96 Season Influenza activity in the United States increased from late October through mid- to late December 1995. Although activity began to decline during January 1996, for the week ending February 3, a total of 19 states reported continuing regional or widespread activity*. Influenza type A(H1N1) predominated in all regions except the Mountain, Pacific, and New England regions, where type A(H3N2) predominated. Influenza type B accounted for only 1% of all isolates nationwide. As of February 3, 1996, of the 19,520 specimens submitted to World Health Organization collaborating laboratories in the United States for respiratory virus testing, 2965 (15%) have been positive for influenza virus: 2925 (99%) were influenza type A, and 40 (1%) were influenza type B. Of the 1803 type A isolates that have been subtyped, 1188 (66%) were type A(H1N1) and 615 (34%) were type A(H3N2). In six of the nine regions in the United States, influenza type A(H1N1) has accounted for from 64% to 89% of subtyped influenza type A strains. In the Mountain, Pacific, and New England regions, influenza type A(H1N1) has circulated at lower levels, accounting for 41%, 46%, and 48% of subtyped influenza A strains, respectively. Regional influenza activity was first reported the week ending October 28, 1995. The number of states reporting regional or widespread activity increased each week from November 5 through December 23, 1995, peaking at 35 states the first week of January 1996. Most outbreaks reported by states to CDC were among school-aged children. Some outbreaks among elderly persons in nursing homes also were reported. The proportion of patients with influenza-like illness (ILI) who visited 150 U.S. sentinel physicians began to increase the week ending December 16; this increase continued through December, with a peak of 7% of total office visits during the week ending December 30. During January, the proportion of patients with ILI began to decline, reaching 3% by the week ending January 20. The proportion of deaths attributed to pneumonia and influenza (P&I) reported from 121 U.S. cities exceeded the epidemic threshold** by a small margin during three of the eight weeks from October 29 through December 23, 1995. The proportion of P&I deaths increased from the week ending December 30 through the week ending January 20 and began to decline the week ending January 27, but remained above the epidemic threshold (Figure 1). Reported by: Participating state and territorial epidemiologists and state public health laboratory directors. World Health Organization collaborating laboratories. Sentinel Physicians Influenza Surveillance System of the American Academy of Family Physicians. Influenza Br and WHO Collaborating Center for Surveillance, Epidemiology, and Control of Influenza, Div of Viral and Rickettsial Diseases, National Center for Infectious Diseases, CDC. Editorial Note: Although influenza activity in the United States peaked during late December 1995, influenza viruses have continued to circulate through early February 1996. The occurrence of a high proportion of reported outbreaks among school-aged children is consistent with patterns during previous influenza seasons when type A(H1N1) viruses have predominated. Influenza A(H1N1) outbreaks among children and younger adults can be associated with high absenteeism in schools and workplaces, and severe secondary medical complications in a small proportion of infected persons. Surveillance findings this season suggest that the incidence of influenza among younger children is substantially higher than usual. Influenza type A(H1N1) has not predominated in the United States since the 1986-87 season, and has circulated at low levels since 1989. As a consequence, a high proportion of children born in the United States since the late 1980s would not be expected to have been exposed to type A(H1N1) viruses before this influenza season. Despite the ability of type A(H1N1) to cause widespread outbreaks, since 1977--when type A(H1N1) viruses reemerged after an absence of 20 years--this strain has not been associated with substantial morbidity among older adults nor with excess mortality. In comparison, type A(H3N2) viruses, which emerged in 1968, more commonly have been associated with excess mortality, greater than 90% of which has occurred among persons aged greater than or equal to 65 years. Epidemics of influenza type B also have been associated with excess mortality (1,2). Although the contribution of type A(H1N1) and type A(H3N2) viruses to the excess P&I mortality this influenza season cannot be assessed precisely, observations during previous influenza seasons strongly suggest that most of these deaths were caused by type A(H3N2) viruses. References 1. Lui KL, Kendal AP. Impact of influenza epidemics on mortality in the United States from October 1972 to May 1985. Am J Public Health 1987;77:712-6. 2. Noble GR. Epidemiological and clinical aspects of influenza. In: Beare AS, ed. Basic and applied research. Boca Raton, Florida: CRC Press, 1982:11-50. *Levels of activity are 1) sporadic~sporadically occurring influenza-like illness (ILI) or culture-confirmed influenza with no outbreaks detected; 2) regional~outbreaks of ILI or culture-confirmed influenza in counties with a combined population of less than 50% of the state's total population; and 3) widespread~outbreaks of ILI or culture-confirmed influenza in counties having a combined population of greater than or equal to50% of the state's total population. **The epidemic threshold is 1.645 standard deviations above the seasonal baseline calculated using a periodic regression model applied to observed percentages since 1983. The baseline was calculated using a robust regression procedure.