Is there an epidemic of HIV/AIDS among heterosexuals in the USA?

The Centers for Disease Control and Prevention (CDC), Atlanta, reports HIV infections and AIDS cases in the United States biannually. Trends in the distribution of HIV/AIDS cases according to sex, race or ethnic group, and various categories of exposure to HIV were analysed. The groups in which there were the greatest percentage increases over time were the group with heterosexual contact and the group for whom the risk factors were not reported or identified. The CDC should be encouraged to provide additional information regarding sexual and drug-using behaviours of those patients listed as "undetermined".

Human-bacteria nitric oxide cycles in HIV-1 infection.

The human intestinal tract harbors a complex microbiotic environment containing commensal bacteria and immunocompetent mucosal cells. There is considerable communication between the bacteria and host cells through dietary constituents and metabolic cycles. We propose that in the pathogenesis of acquired immunodeficiency syndrome (AIDS), the human immunodeficiency virus-1 (HIV-1) triggers a change in a coupled transorganism (human-bacteria) nitric oxide interchange cycle, that may influence the biosynthesis and recycling of nitric oxide (NO) in AIDS patients. Normally, nitric oxide (NO) is produced from arginine through nitrate NO(3)(-), which is ultimately eliminated in the urine and feces. In HIV infection, however, the NO(3)(-) is converted into NO and nitrite NO(2)(-) and recirculated in the body, perhaps as a result of concomitant opportunistic bacterial infections and cellular hypoxia. Due to the efficient coupling of the human-bacteria nitric oxide cycles, persistently high levels of nitrite and the free radicals peroxynitrite (ONOO(-)) may occur in AIDS patients, contributing to the etiology of AIDS-related dementia, persistent immunosuppression and Kaposi's sarcoma.

The cause of invasive cervical cancer could be multifactorial.

Cancer of the cervix is the third most common cancer among women worldwide, with incidence rates ranging from 3.8 per 100,000 women per year in Israel to 48.2 per 100,000 per year in Colombia. Epidemiologic and clinical data suggest that human papillomaviruses, especially HPV-16 and HPV-18, play the major role in the etiology of cervical cancer. However, many investigators acknowledge that HPV is neither necessary nor sufficient in the etiology of cervical cancer and that a multifactorial etiology is likely. HPV cannot be found in every patient with the disease and other factors, such as herpes simplex virus type 2 infection, cigarette smoking, vaginal douching, nutrition, and use of oral contraceptives, have been associated with cervical cancer. In two different animal models, tumors can be produced following exposure to DNA viruses and tars. Using those animal models as prototypes, we propose that the etiology of cervical cancer in humans could be an interaction between DNA viruses, specifically papillomavirus and/or HSV-2 infection, and tar exposure through cigarette smoking and/or tar-based vaginal douching.

Relative rates of AIDS among racial/ethnic groups by exposure categories.

The relative rates of acquired immunodeficiency syndrome (AIDS) were calculated among racial/ethnic populations using Centers for Disease Control and Prevention HIV (human immunodeficiency virus)/Surveillance reports assuming that racial/ethnic distributions reflect that of the US Census Data from 1990. For comparison, a rate of 1 was assigned to whites in each calculation. The overall relative rates were whites--1, African Americans--4.7, Hispanics--3, Asian/Pacific Islanders--0.4, and Native Americans--0.5. Acquired immunodeficiency syndrome surveillance data show higher rates of AIDS for African Americans and Hispanics compared with whites, Asians/Pacific Islanders, and Native Americans. The relative rates for African Americans and Hispanics compared with whites were highest for injecting drug users, heterosexual contact, and pediatric patients. These results led us to explore possible explanations for increased AIDS reporting in African Americans and Hispanics. We then explored available national datasets regarding those variables. The analyses indicate that variables such as access and receptivity to HIV prevention and treatment efforts, race/ethnicity, sexual behaviors, sexually transmitted diseases, socioeconomic status, and substance abuse interact in a complex fashion to influence HIV transmission and progression to AIDS in affected communities.

HIV/AIDS and drug abuse: epidemiology and prevention.

In the United States, the AIDS epidemic is a dynamic process with increasing rates of AIDS reported among women, minority populations, heterosexual men, and users of drugs by routes other than injection. The 1993 CDC AIDS definition change has created some difficulties in interpreting trends in the United States. Drug use continues to represent a significant problem among HIV-infected persons. Several strategies have been advanced to decrease transmission of HIV among drug users, their sexual partners and children. However, more effective and comprehensive prevention and treatment strategies are needed.

The epidemiologic scope of Kaposi's sarcoma.

The unique epidemiology of Kaposi's sarcoma among patients with the acquired immunodeficiency syndrome suggests a multifactorial cause. Although the human immunodeficiency virus (HIV) plays a major role in the pathogenesis of this condition, it is not the sole cause. Other factors, such as a second sexually transmitted organism, genetics, and nitrite inhalant use, may predispose HIV-infected persons to Kaposi's sarcoma.

NIDA technical review: nitrite inhalants.

Nitrite inhalants are commonly abused substances in the US and Europe. "Nitrite inhalants and AIDS" was a popular topic in the early 1980s when the cause of AIDS was not known. With the discovery of HIV, concern about nitrite use wained. However, nitrite inhalant use is associated with behavioral relapse and HIV transmission among gay men, with decreased lymphocyte counts and natural killer cell activity in laboratory studies, and remains a candidate "cofactor" in the pathogenesis of AIDS-related Karposi sarcoma. Discouraging nitrite use continues to be a worthwhile public health goal. Participants recommend specific research efforts.

Identifying substance abuse in primary care.

Family physicians have an opportunity to identify substance abusers years before they have medical complications or present for drug treatment. Occult substance abuse can be effectively identified by simple screening questions and careful attention to clinical indicators during the history and physical examination. Early intervention may have dramatic effects on substance-abusing behavior and may prevent the many adverse medical, psychologic and social effects of substance abuse in these patients.

Measuring inhalant nitrite exposure in gay men: implications for elucidating the etiology of AIDS-related Kaposi's sarcoma.

We reviewed 12 epidemiologic studies conducted among gay men with AIDS to examine the role of potential 'cofactors' in the development of KS. Aspects of the studies reviewed include basic study design, wording of the questionnaires, and published results comparing KS patients with those who developed opportunistic infections indicative of AIDS. The studies included questions about sociodemographics, medical history, use of drugs, travel, and sexual behaviors. Patients were invited to provide blood and/or other specimens for laboratory analysis. The results of the review of epidemiologic studies are inconclusive. Nitrite inhalant use was a variable often associated with KS (five studies). The differences in outcomes of these studies may reflect differences in study designs, sample sizes, timing, quality, and content of interviews regarding nitrites, sexual behaviours and other potential cofactors. Epidemiologic study with careful consideration to content of questionnaires and laboratory testing may yet reveal the causes or cofactors for this tumor.

Nitrite inhalants: history, epidemiology, and possible links to AIDS.

Nitrite inhalants have been commonly abused substances in the United States. Nitrite inhalants and AIDS was a popular topic in the early 1980s, when the cause of AIDS was not known. With the discovery of HIV, concern about nitrite use in the USA waned. However, nitrite inhalant use is associated with behavioral relapse and HIV transmission among gay men, with decreased lymphocyte counts and natural killer cell activity in a few laboratory studies, and it remains a candidate cofactor in the pathogenesis of AIDS-related Kaposi's sarcoma. Discouraging nitrite use continues to be a worthwhile public health goal.

In vitro activity of readily available household materials against HIV-1: is bleach enough?

This report describes experiments assessing the effectiveness against HIV of potential disinfecting agents that are commonly available to IDU when they are sharing syringes. We exposed cell-free HIV, HIV-infected cells, and HIV-infected blood containing known quantities of HIV to household cleaning agents, alcohols, peroxide, and highly acidic materials for 1 min, in order to examine the effects of these materials on the infectivity of the HIV. Undiluted liquid laundry bleach and dilute liquid dish detergent reduced the number of culturable HIV to an undetectable level under the experimental conditions used. Diluted bleach was not completely effective. Other potential disinfecting agents, including ethanol, isopropyl alcohol, and hydrogen peroxide, were unable to disinfect high numbers of HIV-infected cells or infected blood. Liquid dish detergent warrants further study as a possible acceptable alternative to bleach. Our data provide support for recommendations to IDU that they disinfect shared syringes every time between users with full-strength liquid laundry bleach to reduce their risk of acquiring or transmitting HIV. When bleach is not available, liquid dish detergent or other available disinfecting agents such as rubbing alcohol, hydrogen peroxide, or high alcohol content beverages are more effective than water at disinfecting HIV, recognizing that these materials are less effective than bleach. Although these materials are effective, they should not be viewed as a substitute for decreased sharing of injection equipment by IDU, or increased availability of sterile needles and syringes.

HIV risk factors among injecting drug users in five US cities.

OBJECTIVES: To examine factors associated with HIV infection in injecting drug users (IDU), the independent and interactive effects of potential risk factors, and geographic differences in risk factors. METHODS: IDU entering methadone treatment in New York City, Asbury Park and Trenton in New Jersey, Baltimore and Chicago between February 1987 and December 1991 were interviewed using a standard questionnaire and tested for HIV antibodies (n = 4584). Associations of HIV serostatus with race/ethnicity, other demographic characteristics, and injecting and sexual risk behaviors were assessed by logistic regression analyses. RESULTS: African Americans were at increased risk for HIV in four of the five cities, and Puerto Ricans in two cities. Injection in shooting galleries and 'speedball' injection emerged as behavioral variables highly associated with HIV, although interaction of these variables indicates that each variable contributes to HIV risk only in the absence of the other behavior. CONCLUSIONS: Geographic differences in HIV risk factors and the interaction of 'speedball' and shooting gallery use suggest that multiple HIV risk models are needed that reflect seroprevalence rates, variation in risk behaviors, and the social context of risk behaviors. Increased risk among racial/ethnic minorities independent of risk behaviors, suggests the need to examine further potential social and environmental factors, such as the social networks in which injecting and sexual behaviors occur, HIV seroprevalence within these networks, and the locales in which risk behaviors occur.