Jorge Alarcón

Simple, Sensitive, and Specific Detection of Human Immunodeficiency Virus Type 1 Subtype B DNA in Dried Blood Samples for Diagnosis in Infants in the Field

ABSTRACT The detection of virus is used to diagnose human immunodeficiency virus type 1 (HIV-1) infection in infants due to the persistence of maternal antibodies for a year or more. An HIV-1 DNA PCR assay with simple specimen collection and processing was developed and evaluated. Whole blood was collected on filter paper that lysed cells and bound the DNA, eliminating specimen centrifugation and extraction procedures. The DNA remained bound to the filter paper during PCR amplification. Assays of copy number standards showed reproducible detection of 5 to 10 copies of HIV-1 in 5 μl of whole blood. The sensitivity of the assay did not decrease after storage of the standards on filter paper for 3 months at room temperature or after incubation at 37 or 45°C for 20 h. The primers used for nested PCR of the HIV-1pol gene amplified templates from a reference panel of multiple HIV-1 subtypes but did not amplify a subtype A or a subtype C virus from children living in Seattle. The assay had a sensitivity of 98.4% and a specificity of 98.3% for testing of 122 specimens from 35 HIV-1-infected and 16 uninfected children and 43 seronegative adults living in Washington. The assay had a sensitivity of 99% and a specificity of 100% for testing of 102 HIV-1-positive (as determined by enzyme immunoassay) Peruvian women and 6 seropositive and 34 seronegative infants. This assay, with adsorption of whole blood to filter paper and no specimen processing, provides a practical, economical, sensitive, and specific method for the diagnosis of HIV-1 subtype B infection in infants.

Prevention of sexually transmitted diseases (STDs) in female sex workers: prospective evaluation of condom promotion and strengthened STD services.

Background In Perú, a previous study of government-sponsored periodic examinations of female sex workers (FSWs) found no significant impact on rates of sexually transmitted diseases (STDs). Goal This study assessed the impact of technically improved periodic STD services on STD prevalence and on consistent condom use (CCU). Study Design The study involved monthly follow-up of 917 FSWs at two STD clinics, with evaluations before and during implementation of strengthened STD services, which included periodic screening and treatment for gonorrhea, chlamydial infection, trichomoniasis, bacterial vaginosis (BV), and syphilis; counseling; and supply of condoms. Outcome analyses were adjusted for participation bias. Results During 7908 person-months of observation, the prevalences of gonorrhea, chlamydial infection, trichomoniasis, and BV declined significantly and CCU increased significantly, with similar trends in both clinics. During follow-up, gonorrhea, chlamydial infection, trichomoniasis, and BV were negatively associated with follow-up after screening. BV also was positively associated with use of an intrauterine device and negatively with douching. CCU during follow-up was associated with significantly decreased risk of gonorrhea, chlamydial infection, and trichomoniasis. Conclusions Strengthened periodic screening for and treatment of confirmed STD, in addition to condom promotion and provision, represent feasible, effective interventions in commercial sex, and time series analyses can provide a useful approach to evaluating new interventions.

Sexual networks of pregnant women with and without HIV infection.

Objectives: To determine the relationship of HIV infection in pregnant women to sexual network size and other risk factors. Design: Case–control study of women attending the public maternity hospital in Lima, Peru. Methods: We interviewed 75 HIV-seropositive women, 41 of their most recent male partners, and two control groups totaling 137 uninfected pregnant women and 70 of their most recent male partners. Each womans sexual network size was estimated through second and third-generation partnerships over the past year, 5 years and lifetime. Results: Few HIV-seropositive women reported behavioral risk factors for HIV infection, but 79% of male partners were HIV seropositive. Risk factors in male partners included sex with a female sex worker (FSW) or with another man (MSM). The mean 5-year sexual network sizes through the second generation (8.4 persons for HIV-seropositive women, and 2.5 and 1.9 for women in the two control groups) predicted HIV in the women, independently of her own number of partners. These differences were largely attributable to the number of partners reported by male partners. Using data from concurrent studies of FSW and MSM, estimates of 5-year sexual network sizes through the third-generation, excluding contacts with FSW which were protected by consistent condom use, were 672 persons for HIV-seropositive women, and 160 and 224 for women in the two control groups. Conclusions: HIV infection risk among pregnant women in Lima depends largely on their male partners’ risk behaviors. Even monogamous women had very large sexual networks.

High Endemicity of Human T-cell Lymphotropic Virus Type 1 Among Pregnant Women in Peru

Summary: Human T-cell lymphotropic virus type 1(HTLV-1) is associated with adult T-cell leukemia, tropical spastic paraparesis, and other immune-mediated diseases. There are reports of groups with high prevalences of HTLV-1 infection in Peru, but there is limited knowledge of the epidemiology of infection or which routes of infection are most important. We studied 2492 women presenting to a large maternity hospital in Lima for prenatal, delivery, or abortion services. HTLV-1 seropositivity was confirmed in 42 women (1.7%; 95% confidence interval, 1.2-2.2). Seroprevalence increased with age but did not vary by region of birth or recency of migration to Lima. Age greater than 30 years and sexual intercourse before 20 years of age were strongly and independently associated with infection. History of abortion and history of transfusion were of borderline significance. Women whose male partner had a characteristic that might be a marker for risk of sexually transmitted infections were also more likely to be infected. HTLV-1 is common among Peruvians throughout the country and is maintained by a low level of neonatally acquired infection that is amplified by sexual transmission. In addition to screening of the blood supply, instituted in 1997, programs designed to reduce neonatal and sexual transmission should be effective.

Hearing impairment and poverty: the epidemiology of ear disease in Peruvian schoolchildren.

Objectives: 1) To measure prevalence of hearing impairment (HI) in schoolchildren living in poverty in Peru. 2) To identify risk factors for HI and assess its impact on academic performance. Study Design: Cross-sectional. Setting: Elementary schools in an asentimiento humano (shantytown) near Lima, Peru, October 2008 to March 2009. Subjects: Schoolchildren (n = 335), ages six to 19 years. Methods: Audiological health was assessed with pure-tone audiometry, tympanometry, and otoscopy. The primary outcome was HI, defined as average threshold >25 dB HL for 0.5, 1, 2, and 4 kHz, in one or both ears (per World Health Organization/International Organization for Standardization). A questionnaire on health history was administered to parents. Statistical analysis included univariate analysis for χ2 values and odds ratios (ORs), and multivariate logistic regression. Results: HI prevalence: 6.9 percent (95% confidence interval [CI] 4.2%-9.6%). Risk factors for HI (OR, 95% CI, P value): neonatal jaundice (5.59, 1.63-19.2, 0.015), seizure (7.31, 2.50-21.4, 0.0013), hospitalization (4.01, 1.66-9.68, 0.003), recurrent otitis media (5.06, 1.98-12.9, 0.002), past otorrhea (4.70, 1.84-12.0, 0.003), family history of HI at <35 years (2.91, 1.19-7.14, 0.026), tympanic membrane abnormality (13.8, 4.48-42.7, <0.001), cerumen impaction (15.8, 4.71-53.1, <0.001), and eustachian tube dysfunction (4.87, 1.74-13.7, <0.001). HI was an independent predictor of academic failure (3.36, 1.15-9.82, 0.03). Conclusions: Impoverished Peruvian schoolchildren were four to seven times more likely to experience HI than children living in higher-income countries. Untreated middle ear disease in the context of limited access to pediatric care was a major risk factor for HI. Furthermore, HI was associated with worse scholastic achievement. These results support prioritization of pediatric ear health as an essential component of the global health agenda, especially in resource-poor countries.

Cervical Shedding of Human T Cell Lymphotropic Virus Type I Is Associated with Cervicitis

Human T cell lymphotropic virus type I (HTLV-I) is sexually transmitted. The purpose of this study was to determine the prevalence and risk factors for cervical shedding of HTLV-I DNA among Peruvian sex workers. HTLV tax DNA was detected in cervical specimens from 43 (68%) of 63 HTLV-I-infected sex workers and in samples obtained during 113 (52%) of 216 clinic visits between 1993 and 1997. Detection of HTLV DNA was associated with the presence of > or =30 polymorphonuclear cells (PMNs) within cervical mucus per 100x microscopic field (odds ratio [OR], 4.3, 95% confidence interval [CI], 1.8-10.1) and with the presence of cervical secretions (OR, 2.0; 95% CI 1.2-3.4). Hormonal contraceptive use (OR 1.7; 95% CI, 0.8-3.6) and concomitant cervical infection by Chlamydia trachomatis (OR, 1.5; 95% CI, 0.3-4.3) or Neisseria gonorrhoeae (OR, 1.1; 95% CI, 0.6-3.7) were not significantly associated with HTLV-I shedding. Our results suggest that cervicitis may increase cervical HTLV-I shedding and the sexual transmission of this virus.

Cohort Profile: NICHD International Site Development Initiative (NISDI): a prospective, observational study of HIV-exposed and HIV-infected children at clinical sites in Latin American and Caribbean countries

This pediatric protocol has the following scientific goals: to describe the characteristics of HIV-exposed infants and HIV-infected infants children and adolescents cared for at clinical sites in Latin America and the Caribbean to describe early and late outcomes related to HIV disease and ARV therapy and to describe early and late outcomes related to in utero exposure to ARVs and HIV and to neonatal exposure to ARVs.

High Prevalence of Hearing Impairment in HIV-Infected Peruvian Children

Objectives. To measure the prevalence and to identify risk factors of hearing impairment in human immunodeficiency virus-infected children living in Peru. Study design. Cross-sectional observational study. Setting. Two public hospitals and 1 nonprofit center in Lima, Peru, between August 2009 and April 2010. Subjects. A total of 139 HIV-infected children, ages 4 to 19 years. Methods. Hearing impairment and otologic health were assessed with pure tone audiometry, tympanometry, and otoscopy. The primary outcome was hearing loss, defined as average threshold >25dB for 0.5, 1, 2, and 4 kHz, in one or both ears. Historical and socioeconomic information was obtained through parental survey and medical chart review. Statistical analysis included univariate analysis and multivariate logistic regression. Results. Fifty-four (38.8%) of 139 children had hearing impairment. On multivariate analysis, risk factors included: tympanic membrane perforation (odds ratio [OR] 7.08; 95% confidence interval [CI], 1.65-30.5; P = .01), abnormal tympanometry (OR 2.71; 95% CI, 1.09-6.75; P = .03), cerebral infection (OR 11.6; 95% CI, 1.06-126; P = .05), seizures (OR 5.20; 95% CI, 1.21-22.4; P = .03), and CD4 cell count <500 cells/mm3 (OR 3.53; 95% CI, 1.18-10.5; P = .02). Conclusions. The prevalence of hearing impairment in HIV-infected children in Lima, Peru was 38.8%. Middle ear disease, prior cerebral infection, and low CD4 cell count were significantly associated with hearing impairment. The high prevalence of hearing impairment emphasizes the need for periodic hearing assessment in the routine clinical care of HIV-infected children.

The NICHD International Site Development Initiative perinatal cohorts (2002–09)

70provided by the protocol, and initiation and manage-ment of ARV treatment or prophylaxis were decidedby individual site investigators as per ARV availability,Published by Oxford University Press on behalf of the International Epidemiological Association 2011 International Journal of Epidemiology 2011;1–8doi:10.1093/ije/dyr024

Quantitative assessment of subclinical spasticity in human T-cell lymphotropic virus type I infection.

Objective: To compare human T-cell lymphotrophic virus type I (HTLV-I) seropositive and seronegative women for symptoms and signs of spasticity. Background: Infection with HTLV-I causes tropical spastic paraparesis/HTLV-I–associated myelopathy (TSP/HAM). Certain populations, including female commercial sex workers (FSW), are at increased risk of developing this infection. Fewer than 5% of HTLV-I–seropositive persons develop TSP/HAM, which is typically associated with spasticity. Methods: Cross-sectional study of 255 registered FSW in Callao, Perú, involving a questionnaire detailing demographics and neurologic symptoms, standard neurologic examination, quantitative assessment of spasticity (QSA) of muscle tone, and serologic testing for HTLV-I. Participants and examiners were blinded to serology results. Results: On the questionnaire and neurologic examination, none of the 32 HTLV-I–seropositive or 223 seronegative women had signs or symptoms of spasticity. However, mean values on QSA were significantly higher among seropositive women (27.1 Newton-meters/radian [N-m/r]) than among seronegative women (21.6 N-m/r, p = 0.01), indicating a subclinical increase in lower extremity tone. With values of QSA divided into tertiles, and the first tertile serving as the comparison group, the odds ratio for seropositivity was 1.4 (95% confidence interval [CI] 1.0 to 2.0) in the second and 3.1 (95% CI 2.2 to 4.3) in the third tertile, after adjusting for age and place of birth. Conclusions: Although a standard neurologic evaluation could not distinguish between women with and without HTLV-I infection, QSA indicated significantly increased lower extremity tone in those with infection. Long-term follow-up will determine whether these subclinical findings in asymptomatic women progress to overt TSP/HAM.