Division of HIV/AIDS Prevention

Despite the completion of the Treponema pallidum genome project, only minor genetic differences have been found between the subspecies that cause venereal syphilis (ssp. pallidum) and the nonvenereal diseases yaws (ssp. pertenue) and bejel (ssp. endemicum). In this paper, we describe sequence variation in the arp gene which allows straightforward differentiation of ssp. pallidum from the nonvenereal subspecies. We also present evidence that this region is subject to positive selection in ssp. pallidum, consistent with pressure from the immune system. Finally, the presence of multiple, but distinct, repeat motifs in both ssp. pallidum and Treponema paraluiscuniculi (the pathogen responsible for rabbit syphilis) suggests that a diverse repertoire of repeat motifs is associated with sexual transmission. This study suggests that variations in the number and sequence of repeat motifs in the arp gene have clinical, epidemiological, and evolutionary significance.

Trichomonas vaginalis infection is a common sexually transmitted protozoal infection and is associated with several adverse health outcomes, such as preterm birth, delivery of a low-birth weight infant, and facilitation of sexual transmission of human immunodeficiency virus. The annual incidence in the United States has been estimated to be 3-5 million cases. However, there are no data on the prevalence of trichomoniasis among all reproductive-age women. We estimated the prevalence of T. vaginalis infection from a nationally representative sample of women in the United States.

To further advance our understanding of the efficacy of inventory-based premarital education programs, this study examined whether the effects of the PREPARE program varied by delivery format. Following participation in the program, engaged couples exhibited positive gains in knowledge, felt more confident in their relationship, engaged in more positive conflict management behaviors, and felt more satisfied with their relationship. No differences were found between participants who completed a series of conjoint sessions versus a 1-day group workshop. These findings highlight the robustness of premarital education and suggest group workshops can have similar effectiveness as the more prevalent conjoint sessions.

Background: Preliminary review of data from the Vaccine Adverse Event Reporting System (VAERS), 1991-1994, revealed that more serious adverse events were reported in children who received a specific brand of recombinant hepatitis B (HepB) vaccine. Objective: To compare the post-marketing safety experience of the two recombinant HepB vaccines licensed for use in infants and children in the United States. Design: Review of a case series derived from passive surveillance data in the national VAERS. A retrospective cohort study using data from one health maintenance organization participating in Vaccine Safety Datalink (VSD), a computerized record linkage system. Populations Studied: U.S. children, ages birth-10 years for whom adverse events after HepB vaccine were reported to VAERS, 1991VAERS, -1994. Children, ages birth-6 years, who received HepB vaccine at Kaiser Permanente Medical Care Program, Northern California, 1991. Main Outcome Measures: VAERS reporting rates for each vaccine by manufacturer were calculated from the numbers of reported events occurring within 30 days of HepB vaccination and the number of doses distributed by the manufacturers. VSD event rates for each vaccine were calculated from the numbers of hospitalization or emergency room visits within 30 days of HepB vaccination and the number of vaccine doses administered to the cohort. Results: In VAERS, higher rates of serious events (i.e., life threatening or resulting in hospitalization or permanent disability) were reported in children who received Vaccine A vs. Vaccine B (relative risk [RR]: 3.13-8.18, P Ͻ 0.01), particularly by those vaccinated in the private (RR: 7.62-28.58, P Ͻ 0.01), but not public sector (RR: 2.12, P ϭ 0.19). Similar types of events were reported in recipients of both vaccines. In contrast, analysis of VSD data showed no significant difference in rates of hospitalization or ER visits in children who received either HepB vaccine (RR: 0.96-1.25, P Ͼ 0.05). Conclusions: Our investigation reveals that it is unlikely there is a true difference between rates of serious events temporally associated with the two HepB vaccines in children. This study demonstrates the dual roles played by VAERS and VSD in providing a more complete picture of the post-marketing safety profile of childhood vaccines, and underscores the importance of using other analytic studies to evaluate findings from passive surveillance systems of adverse events. j clin epidemiol 51;6: 503-510, 1998.

OBJECTIVES: This study examined whether there is a risk that tetanus-toxoid-containing vaccines could cause Guillain-Barré syndrome and, if so, how large the risk is. METHODS: This study was based on previous active surveillance epidemiological studies of Guillain-Barré syndrome and vaccination history. RESULTS: A background rate of 0.3 cases of Guillain-Barré syndrome per million person-weeks has been estimated. By chance, 2.2 people with the syndrome would have received tetanus-toxoid-containing vaccine within the 6 weeks before onset, yet only 1 person had done so. Data on children show similar results. CONCLUSIONS: If an association exists, it must be extremely rare and not of public health significance.

Objectives: To describe adults/adolescents (age 13 years and older) living with undiagnosed HIV infection in the United States at the end of 2006. Methods: HIV prevalence and percentage undiagnosed were estimated from cumulative HIV incidence using an extended backcalculation model (using both HIV and AIDS data, the time of first diagnosis with HIV, and disease severity at diagnosis) and estimated cumulative deaths. Results: An estimated 1,106,400 adults/adolescents (95% confidence interval = 1,056,400-1,156,400) were living with HIV in the United States at the end of 2006; overall, 21.0% (232,700; 95% confidence interval = 221,200-244,200) were undiagnosed. Whites had the lowest percentage undiagnosed (18.8%) compared with Hispanics/Latinos (21.6%), blacks/African Americans (22.2%), American Indians/Alaska Natives (25.8%), and Asians/Pacific Islanders (29.5%; all P , 0.001). Persons with a behavioral risk of injection drug use (IDU) had the lowest percentage undiagnosed (female IDU: 13.7% and male IDU: 14.5%); men exposed through heterosexual contact had the highest (26.7%) followed by men who have sex with men (23.5%). Conclusions: Differences in undiagnosed HIV were evident across demographic and behavior groups. Effective testing programs and early access to treatment and prevention services are necessary to reduce undiagnosed HIV infections and HIV prevalence.

Context Incidence of human immunodeficiency virus (HIV) in the United States has not been directly measured. New assays that differentiate recent vs long-standing HIV infections allow improved estimation of HIV incidence. Conclusions This study provides the first direct estimates of HIV incidence in the United States using laboratory technologies previously implemented only in clinicbased settings. New HIV infections in the United States remain concentrated among men who have sex with men and among black individuals.

To quantify the effects of cumulative months of pregnancy, breast feeding, and oral contraceptive use on the risk of developing epithelial ovarian cancer, the authors used data collected for the Cancer and Steroid Hormone Study-a multicenter, population-based, case-control study. Detailed reproductive histories were obtained from 436 women aged 20-54 with epithelial ovarian cancer newly diagnosed between December 1980 and December 1982, and from 3833 women aged 20-54 selected at random from the same geographic areas. Estimated relative risks of epithelial ovarian cancer were 0.6 (95% confidence interval (CI) 0.5-0.8) for women who had ever been pregnant, 0.6 (95% CI 0.5-0.8) for women who had ever breast fed, and 0.5 (95% CI 0.5-0.7) for women who had ever used oral contraceptives. Logistic regression analysis revealed a strong trend in decreasing risk of epithelial ovarian cancer with increasing cumulative months of pregnancy; this effect was less pronounced in women aged 50-54 than in younger women. In contrast, a marked reduction in risk was associated with ever having breast fed or used oral contraceptives, while the decrease in risk from additional months of either of these exposures was less than that for pregnancy.

Background The administration of the diphtheria and tetanus toxoids and whole-cell pertussis (DTP) vaccine and measles, mumps, and rubella (MMR) vaccine has been associated with seizures. We studied the relation between these vaccinations and the risk of a first seizure, subsequent seizures, and neurodevelopmental disability in children. Methods This cohort study was conducted at four large health maintenance organizations and included reviews of the medical records of children with seizures. We calculated the relative risks of febrile and nonfebrile seizures among 679,942 children after 340,386 vaccinations with DTP vaccine, 137,457 vaccinations with MMR vaccine, or no recent vaccination. Children who had febrile seizures after vaccination were followed to identify the risk of subsequent seizures and other neurologic disabilities. Results Receipt of DTP vaccine was associated with an increased risk of febrile seizures only on the day of vaccination (adjusted relative risk, 5.70; 95 percent confidence interval, 1.98 to 16.42). Receipt of MMR vaccine was associated with an increased risk of febrile seizures 8 to 14 days after vaccination (relative risk, 2.83; 95 percent confidence interval, 1.44 to 5.55). Neither vaccination was associated with an increased risk of nonfebrile seizures. The number of febrile seizures attributable to the administration of DTP and MMR vaccines was estimated to be 6 to 9 and 25 to 34 per 100,000 children, respectively. As compared with other children with febrile seizures that were not associated with vaccination, the children who had febrile seizures after vaccination were not found to be at higher risk for subsequent seizures or neurodevelopmental disabilities. Conclusions There are significantly elevated risks of febrile seizures after receipt of DTP vaccine or MMR vaccine, but these risks do not appear to be associated with any long-term, adverse consequences.

was to identify risk factors for rotavirus gastroenteritis requiring hospitalization. Patients: Cases were children Յ59 months of age who were admitted with acute gastroenteritis (AGE) and found to have rotavirus infection. Controls were selected from a birth certificate registry (Cincinnati and Providence) or a registry of patients from a large practice consortium in 11 locations (New Orleans). Results: Three hundred forty-nine rotavirus-infected cases and 1242 control subjects were enrolled. Breast feeding was protective against hospitalization for rotavirus AGE for infants Ͻ6 months of age. (odds ratio ͓OR͔, 5.1; 95% confidence interval ͓CI͔, 1.2-13.2). Low-birth-weight (Ͻ2500 g) infants had increased risk for hospitalization even beyond the first few months of life (OR, 2.8; 95% CI, 1.6-5.0). Children in child care were more likely to be hospitalized for rotavirus AGE than those cared for at home, particularly those Ն24 months of age (OR, 3.0; 95% CI, 1.8-5.3). Other characteristics associated with rotavirus AGE hospitalization were children Ͻ24 months of age covered by Medicaid or without insurance (OR, 2.1; 95% CI, 1.4-3.2) and having another child in the house Ͻ24 months of age (OR, 1.6; 95% CI, 1.1-2.3). The data suggest that maternal age Ͻ25 years (OR, 1.4; 95% CI, 1.0-2.0) and a mother with less than a high school education (OR, 1.5; 95% CI, 1.0-2.3) may also increase risk of rotavirus hospitalization. Conclusion: There are socioeconomic and environmental factors and aspects of the child's medical and dietary history that identify children at risk for hospitalization with rotavirus AGE.

Background. Despite the dramatic pertussis decrease since the licensure of whole-cell pertussis (diphtheria-tetanus toxoids-pertussis [DTP]) vaccines in the middle 1940s, pertussis remains endemic in the United States and can cause illness among persons at any age; >11000 pertussis cases were reported in 2003. Since July 1996, in addition to 2 DTP vaccines already in use, 5 acellular pertussis (diphtheria-tetanus toxoids-acellular pertussis [DTaP]) vaccines were licensed for use among infants; 3 DTaP vaccines were distributed widely during the study period. Because of the availability of 3 DTaP and 2 DTP vaccines and the likelihood of the vaccines being used interchangeably to vaccinate children with the recommended 5-dose schedule, measuring the effectiveness of the pertussis vaccines was a high priority. Objective. To measure the pertussis vaccine effectiveness (VE) among US children 6 to 59 months of age. Design. We conducted a case-control study in the Cincinnati, Ohio, metro...

Since 1966, the Advisory Committee on Immunization Practices (ACIP) has recommended tetanus-diphtheria toxoid (Td) be used instead of single antigen tetanus toxoid (TT) because, while both vaccines protect against tetanus, only Td protects against diphtheria. Despite this recommendation, approximately 2.5 million doses of TT were distributed annually from 1991 to 1997. One possible explanation for the continued use of TT is concern about the relative safety of Td. Small clinical trials found Td to be associated with a higher rate of local vaccine-associated adverse events (VAEs) than TT. To determine if the findings from the trials would hold up on a larger scale, we compared the rate of reporting to the Vaccine Adverse Event Reporting System (VAERS), a passive reporting system, after either vaccine from 1991 to 1997. There were 40 reports per million doses of Td, and 27 reports per million doses of TT, for a reporting rate ratio of 1.4. Reporting rates to VAERS are lower than the rates of VAEs identified in the clinical trials, but the magnitude of the difference in VAEs following TT versus Td is similar. While reporting rates are lower after TT than Td, rates of reported VAEs after both vaccines are low.

IMPORTANCE Early diagnosis of human immunodeficiency virus (HIV) infection, prompt linkage to and sustained care, and antiretroviral therapy are associated with reduced individual morbidity, mortality, and transmission of the virus. However, levels of these indicators may differ among population groups with HIV. Disparities in care and treatment may contribute to the higher incidence rates among groups with higher prevalence of HIV. OBJECTIVE To examine differences between groups of persons living with HIV by sex, age, race/ethnicity, and transmission category at essential steps in the continuum of care. DESIGN AND SETTING We obtained data from the National HIV Surveillance System of the Centers for Disease Control and Prevention to determine the number of persons living with HIV who are aware and unaware of their infection using back-calculation models. We calculated the percentage of persons linked to care within 3 months of diagnosis on the basis of CD4 level and viral load test results. We estimated the percentages of persons retained in care, prescribed antiretroviral therapy, and with viral suppression using data from the Medical Monitoring Project, a surveillance system of persons receiving HIV care in select areas representative of all such persons in the United States. PARTICIPANTS All HIV-infected persons in the United States. MAIN OUTCOMES AND MEASURES Percentage of persons living with HIV who are aware of their infection, linked to care, retained in care, receiving antiretroviral therapy, and achieving viral suppression. RESULTS Of the estimated 1 148 200 persons living with HIV in 2009 in the United States, 81.9% had been diagnosed, 65.8% were linked to care, 36.7% were retained in care, 32.7% were prescribed antiretroviral therapy, and 25.3% had a suppressed viral load (Յ200 copies/mL). Overall, 857 276 persons with HIV had not achieved viral suppression, including 74.8% of male, 79.0% of black, 73.9% of Hispanic/Latino, and 70.3% of white persons. The percentage of blacks in each step of the continuum was lower than that for whites, but these differences were not statistically significant. Among persons with HIV who were 13 to 24 years of age, only 40.5% had received a diagnosis and 30.6% were linked to care. Persons aged 25 to 34, 35 to 44, and 45 to 54 years were all significantly less likely to achieve viral suppression than were persons aged 55 to 64 years. CONCLUSIONS AND RELEVANCE Significant age disparities exist at each step of the continuum of care. Additional efforts are needed to ensure that all persons with HIV receive a diagnosis and optimal care to reduce morbidity, mortality, disparities in care and treatment, and ultimately HIV transmission. Ensuring that people stay in care and receive treatment will increase the proportion of HIV-infected individuals who achieve and maintain a suppressed viral load.

Administration of high-titre measles vaccine (Edmonston-Zagreb (EZ) at > 10(5) plaque-forming units (PFU) per dose) before the age of 9 months has been recommended in areas with high measles mortality before the routine age of immunization after 9 months. The study compares the long-term survival after high-titre measles immunization at 5 months of age with that following routine immunization with standard-titre vaccine at 10 months of age. At 5 months of age the high-titre group received Edmonston-Zagreb (EZ-HT, 5 months) or Schwarz (SW-HT, 5 months) at titres > 10(5) PFU per dose, while the standard-titre group received placebo at 5 months of age and < 10(4) PFU per dose of Schwarz vaccine at 10 months (SW-std, 10 months). All the children were followed up to at least 36 months of age. The mortality ratio (MR) for infants in the EZ-HT, 5 months and SW-HT, 5 months groups was 1.32 (P = 0.089) and 1.45 (P = 0.092), respectively, which did not differ significantly from that ...