Changing risk factors for HIV infection

Temporally Varying Relative Risks for Infectious Diseases: Implications for Infectious Disease Control

Risks for disease in some population groups relative to others (relative risks) are usually considered to be consistent over time, although they are often modified by other, nontemporal factors. For infectious diseases, in which overall incidence often varies substantially over time, the patterns of temporal changes in relative risks can inform our understanding of basic epidemiologic questions. For example, recent studies suggest that temporal changes in relative risks of infection over the course of an epidemic cycle can both be used to identify population groups that drive infectious disease outbreaks, and help elucidate differences in the effect of vaccination against infection (that is relevant to transmission control) compared with its effect against disease episodes (that reflects individual protection). Patterns of change in the age groups affected over the course of seasonal outbreaks can provide clues to the types of pathogens that could be responsible for diseases for which an infectious cause is suspected. Changing apparent efficacy of vaccines during trials may provide clues to the vaccine's mode of action and/or indicate risk heterogeneity in the trial population. Declining importance of unusual behavioral risk factors may be a signal of increased local transmission of an infection. We review these developments and the related public health implications.

Sociodemographic differences among HIV-positive and HIV-negative recently pregnant women in Mexico City: A case-control study

National HIV preventive programs in Mexico focus on high-risk groups that do not consider women, apart from prenatal screening. Nonetheless, the epidemic in women is growing, and there is a need to better understand sociodemographic factors in women living with HIV (WLH). We performed a case-control study in Mexico City, including HIV+ and HIV- women with a recent pregnancy to compare their sociodemographic characteristics and describe the circumstances of diagnosis in HIV+ women, as well as prenatal screening frequency in both groups. Fifty cases and 102 controls were interviewed. HIV+ women were more frequently the only economic support of the family (20% vs 0%, P < .0001). Thirty-eight percent of cases had their first pregnancy at ≤18 years, versus 16% of controls (odds ratio 2.47, 95% confidence interval 1.07-5.72, P = .03); 16% of cases had lived in the street; 6% reported transactional sex, versus none of the controls (P < .0001). In the multivariate analysis, there was strong evidence of an association between HIV infection and age at the time of the interview, history of sexually transmitted diseases, substance abuse, history of violence, and civil status. Only 6% of controls were tested for HIV during prenatal follow-up. WLH in this study faced important social vulnerability. Targeting women living in these social contexts might increase early diagnosis and could tailor HIV prevention strategies. Prenatal coverage needs to be improved and should represent a national priority.

HIV vulnerability and condom use among migrant women factory workers in Puebla, Mexico

International migration is associated with increased HIV vulnerability, but little is known about the vulnerability of internal migrants. This qualitative study explored perceptions of HIV and condom use among Mexican migrant female factory workers. Migration and male sexual infidelity contributed to increased HIV vulnerability and unprotected sex was ubiquitous. The dominant cultural discourse that dichotomizes "good" (monogamous) and "bad" (sexually stigmatized) women, and male partner's resistance, were barriers to condom use. Women's positive attitudes toward the dual protection (pregnancy and sexually transmitted infections) offered by condoms and sexual agency expressed by refusing unwanted sexual contact are resources for HIV prevention.

Prevalence and risk factors of hepatitis C virus, hepatitis B virus, and human immunodeficiency virus in multiply transfused recipients in Mexico

BACKGROUND

Transfusion-transmitted viral infection (TTI) is a major problem in patients receiving blood products. Monitoring high-risk patients is essential for assessing the epidemiology of blood-borne infections.

STUDY DESIGN AND METHODS

A 1-year, cross-sectional seroprevalence study in patients with a history of multiple transfusions was conducted. Peripheral blood samples were titered to detect serologic markers of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV). The presence of these viruses and demographic, behavioral, and medical traits were assessed.

RESULTS

A total of 300 male and female multiply transfused patients with a mean age of 30.7 (+/-17.5) years were studied. The prevalence was 13.7% for HCV, 7% for HBV, and 1.7% for HIV. Patients with hemophilia had the highest prevalence for HCV and HIV infections, and hemodialyzed patients, for HBV infection. The risk factors related to acquired HCV were hemophilia (odds ratio [OR], 5.6; 95% confidence interval [CI], 2.5-12.6), more than five hospitalizations (OR, 3.8; 95% CI, 1.6-8.9), and having received a transfusion before mandatory screening in 1993 (OR, 8.4; 95% CI, 2.0-34.6), and for HIV, having received a transfusion before 1987 (OR, 19.0; 95% CI, 2.0-177.7). The main risk factors for HBV were having end-stage renal disease and being treated with hemodialysis (OR, 3.7; 95% CI, 1.4-9.9) and transplantation (OR, 4.2; 95% CI, 1.4-12.1).

CONCLUSIONS

This study showed that HCV infection was more frequently identified than HBV and HIV infections in multiply transfused Mexican patients. Additionally, several risk factors are associated with TTI such as mandatory screenings before 1987 and 1993, which were the most important for HIV and HCV infections but not for HBV.