Women account for almost half of the approximately 40 million people worldwide living with an HIV infection. Higher proportions exist in developing countries, especially in sub-Saharan Africa, where 60 percent of cases and 75 percent of infected people between the ages of 15 and 24 are women. Social determinants and physiological factors affect female vulnerability. For many reasons, women are more susceptible to HIV infection. Infections in women of child-bearing age can result in HIV transmission to infants.
In the United States, the estimated number of AIDS cases increased 15 percent among women and only 1 percent among men from 1999-2003. Most cases involve young women and women of color. The rate of AIDS diagnoses for African-American women is 25 times that of white women, and four times the rate for Hispanic women. The majority (80 percent) of infections are due to high-risk heterosexual transmission or to injecting drug use (19 percent). These same risk factors are responsible for cases among women in Asia and eastern Europe. In Africa, almost all cases involve heterosexual contact.
A number of social issues put females at increased risk for infection. Worldwide, women often do not have societal position or wealth. They commonly marry older, more sexually experienced men, who are more capable of providing support. Cultural norms often do not allow women to control their personal sexuality. Lack of education limits change. Often, there is an undercurrent of violence.
Physiologically, women are more susceptible to HIV infections than are men. Increased susceptibility has been linked to a number of factors, including use of hormonal contraceptives and a greater prevalence of sexually transmitted diseases (STDs). The relationship between birth control pills and elevated HIV rates of infection is still being debated. Several studies do indicate accelerated disease progression with use. Of course, the use of hormonal contraceptives is higher in high-risk populations, such as young females.
Affixing causality becomes more difficult because the initial stages or steps of HIV infection are not well known. Heterosexual contact is the major path for infection in women. Infection requires passage of the virus through the normally protective mucosal barrier. The presence of ulcerative STDs allows for easier passage and increased chances of transmission. STDs also increase the number of circulating inflammatory cells, which are prime host cells for HIV. Such processes are difficult to study, especially concerning the events of viral acquisition.
Adolescent females seem to be the most vulnerable group. This could involve their high-risk behaviors, or the presence of an immature genital tract. Often, there is increased cervical ectopy and/or exposed columnar epithelium. Recent data indicate a two-fold greater chance of HIV acquisition during pregnancy and the early postpartum period. This may involve increased levels of progesterone and increased ectopy.
There is a growing amount of information that supports further feminization of the HIV/AIDS pandemic. This includes both social and biological factors. One key element links infection rates with regional gender norms that affect the application of power within interpersonal relationships. Prevention would improve with greater use of both male and female condoms as well as microbiocides. More information is needed concerning the influence of hormones on disease progression.
Both men and women must be better educated concerning HIV transmission and other STDs. This would involve schemes that help negotiate safer sex, encourage testing and - if necessary - treatment. There is a need for at-risk people to maintain their health and protect their partners. The first commercially available HIV test appeared in 1985. More accurate diagnosing, counseling, treatment, and care have developed since 1985.
There are approximately 1 million people in the United States who are HIV positive. Nearly 25 percent of those infected are not aware of their infections. HIV testing has become easier, more accessible, and less invasive. Persons who know they are infected can benefit from advances in medical care to prolong their lives. They also can prevent transmission of HIV to others.
OSAP, the Organization for Safety & Asepsis Procedures, is dentistry’s prime source for evidence-based information on infection control, and prevention and human safety and health. Further information concerning HIV is available on the OSAP Web site at www.osap.org.
Dr. Charles John Palenik is an assistant director of Infection Control Research and Services at the Indiana University School of Dentistry. Dr. Palenik is the co-author of the popular “Infection Control and Management of Hazardous Materials for the Dental Team.” He serves as chair of the OSAP publications committee. Questions about this article or any infection-control issue may be directed to [email protected].