Perinatal HIV infection is characterized by a sustained high-level viremia and a high risk of rapid progression to AIDS, indicating a failure of immunologic containment of the virus. We hypothesized that age-related differences in the specificity or function of HIV-specific T cells may influence HIV RNA levels and clinical outcome following perinatal infection. In this study, we defined the HIV epitopes targeted by 76 pediatric subjects (47 HIV infected and 29 HIV exposed, but uninfected), and assessed the ability of HIV-specific CD8 and CD4 T cells to degranulate and produce IFN-γ, TNF-α, and IL-2. No responses were detected among HIV-uninfected infants, whereas responses among infected subjects increased in magnitude and breadth with age. Gag-specific responses were uncommon during early infancy, and their frequency was significantly lower among children younger than 24 mo old (p = 0.014). Importantly, Gag responders exhibited significantly lower HIV RNA levels than nonresponders (log viral load 5.8 vs 5.0; p = 0.005). Both the total and Gag-specific T cell frequency correlated inversely with viral load after correction for age, whereas no relationship with targeting of other viral proteins was observed. Functional assessment of HIV-specific T cells by multiparameter flow cytometry revealed that polyfunctional CD8 cells were less prevalent in children before 24 mo of age, and that HIV-specific CD4 cell responses were of universally low frequency among antiretroviral-naive children and absent in young infants. These cross-sectional data suggest that qualitative differences in the CD8 response, combined with a deficiency of HIV-specific CD4 cells, may contribute to the inability of young infants to limit replication of HIV.

No abstract

Background: Vaccines, that target human papillomavirus (HPV) high risk genotypes 16 and 18, have recently been developed. This study was aimed at determining genotypes commonly found in high-risk and multiple-HPV infections in Jamaican women. Two hundred and fifty three (253) women were enrolled in the study. Of these, 120 pregnant women, aged 15-44 years, were recruited from the Ante Natal Clinic at the University Hospital of the West Indies and 116 nonpregnant, aged 19-83, from a family practice in Western Jamaica. Cervical cell samples were collected from the women and HPV DNA was detected using Polymerase Chain Reaction and Reverse Line Hybridization. HPV genotypes were assessed in 236 women. Data were collected from

Due to overlapping clinical features with other febrile illnesses, the diagnosis of leptospirosis is often overlooked, resulting in delay in treatment and increased mortality. In this study the prevalence of leptospirosis was determined in 590 patients with dengue-like illnesses using the Leptospira IgM dipstick and dengue enzyme-linked immunosorbent assays. Leptospira IgM antibodies were found in 27 (5.0%) patients. Dengue IgM negative (6.9% versus 2.5%, P < 0.05) and dengue IgG positive patients (8.0% versus 3.5%, P < 0.01) were more likely to be leptospira IgM positive. Fever, skin rash, central nervous system and respiratory involvement were the most common presenting features. The presence of arthralgia (P = 0.016), hepatitis (P = 0.000), jaundice (P = 0.003), splenomegaly (P = 0.041) and haematuria (P = 0.029) were associated with leptospirosis. In countries with an endemicity of leptospirosis and dengue it is important that patients with dengue-like illnesses, especially those with no serological evidence of current primary dengue infection, be investigated for leptospirosis.

Dengue fever, a mosquito borne viral infection, is endemic to Jamaica. The seroprevalence of dengue IgG and IgM antibodies were determined in 277 healthy Jamaicans by enzyme linked immunosorbent assay (ELISA). The seroprevalence of dengue IgG antibodies was 100% (277/277) while dengue IgM antibodies were found in 3.6% (10/277). A statistically significant association was found between the presence of dengue IgM antibodies and gender (males 10/105, 9.5% vs females 0/172, 0.0%); chi(2) = 17.0, p=0.000.The high seroprevalence rate of dengue IgG antibodies and the presence of dengue IgM in the healthy population are in keeping with the endemicity of the virus in Jamaica. Therefore tests for dengue IgG antibodies are of limited usefulness in Jamaica and can be safely excluded from diagnostic testing as a cost saving measure. Serological diagnosis of current dengue infection should be centred around the dengue IgM tests although the limitations in the predictive values of such tests should also be considered. The results also suggest that the risk of emergence of the more severe forms of dengue, dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS) in the Jamaican population, due to the presence of enhancing antibodies, is high.