Prevalence and Risk Factors of Sexually Transmitted Infections and Cervical Neoplasia in Women from a Rural Area of Southern Mozambique

There is limited information on the prevalence of sexually transmitted infections and the prevalence of cervical neoplasia in rural sub-Saharan Africa. This study describes the prevalence and the etiology of STIs and the prevalence of cervical neoplasia among women in southern Mozambique. An age-stratified cross-sectional study was performed where 262 women aged 14 to 61 years were recruited at the antenatal clinic (59%), the family-planning clinic (7%), and from the community (34%). At least one active STI was diagnosed in 79% of women. Trichomonas vaginalis was present in 31% of all study participants. The prevalence of Neisseria gonorrhea and Chlamydia trachomatis were 14% and 8%, respectively, and Syphilis was diagnosed in 12% of women. HPV DNA was detected in 40% of women and cervical neoplasia was diagnosed in 12% of all women. Risk factors associated with the presence of some of the STIs were being divorced or widowed, having more than one sexual partner and having the partner living in another area. A higher prevalence was observed in the reproductive age group and some of the STIs were more frequently diagnosed in pregnant women. STI control programs are a priority to reduce the STIs burden, including HIV and cervical neoplasia

Safety, Immunogenicity and Duration of Protection of the RTS,S/AS02D Malaria Vaccine: One Year Follow-Up of a Randomized Controlled Phase I/IIb Trial

The RTS,S/AS02(D) vaccine has been shown to have a promising safety profile, to be immunogenic and to confer protection against malaria in children and infants.We did a randomized, controlled, phase I/IIb trial of RTS,S/AS02(D) given at 10, 14 and 18 weeks of age staggered with routine immunization vaccines in 214 Mozambican infants. The study was double-blind until the young child completed 6 months of follow-up over which period vaccine efficacy against new Plasmodium falciparum infections was estimated at 65.9% (95% CI 42.6-79.8, p<0.0001). We now report safety, immunogenicity and estimated efficacy against clinical malaria up to 14 months after study start. Vaccine efficacy was assessed using Cox regression models. The frequency of serious adverse events was 32.7% in the RTS,S/AS02(D) and 31.8% in the control group. The geometric mean titers of anti-circumsporozoite antibodies declined from 199.9 to 7.3 EU/mL from one to 12 months post dose three of RTS,S/AS02(D), remaining 15-fold higher than in the control group. Vaccine efficacy against clinical malaria was 33% (95% CI: -4.3-56.9, p = 0.076) over 14 months of follow-up. The hazard rate of disease per 2-fold increase in anti-CS titters was reduced by 84% (95% CI 35.1-88.2, p = 0.003).The RTS,S/AS02(D) malaria vaccine administered to young infants has a good safety profile and remains efficacious over 14 months. A strong association between anti-CS antibodies and risk of clinical malaria has been described for the first time. The results also suggest a decrease of both anti-CS antibodies and vaccine efficacy over time.ClinicalTrials.gov NCT00197028

The Role of Age and Exposure to Plasmodium falciparum in the Rate of Acquisition of Naturally Acquired Immunity: A Randomized Controlled Trial

Background: The rate of acquisition of naturally acquired immunity (NAI) against malaria predominantly depends on transmission intensity and age, although disentangling the effects of these is difficult. We used chemoprophylaxis to selectively control exposure to P. falciparum during different periods in infancy and explore the effect of age in the build-up of NAI, measured as risk of clinical malaria.\ud \ud Methods and Findings: A three-arm double-blind randomized placebo-controlled trial was conducted in 349 infants born to Mozambican HIV-negative women. The late exposure group (LEG) received monthly Sulfadoxine-Pyrimethamine (SP) plus Artesunate (AS) from 2.5–4.5 months of age and monthly placebo from 5.5–9.5 months; the early exposure group (EEG) received placebo from 2.5–4.5 months and SP+AS from 5.5–9.5 months; and the control group (CG) received placebo from 2.5–9.5 months. Active and passive case detection (PCD) were conducted from birth to 10.5 and 24 months respectively. The primary endpoint was time to first or only episode of malaria in the second year detected by PCD. The incidence of malaria during the second year was of 0.50, 0.51 and 0.35 episodes/PYAR in the LEG, EEG and CG respectively (p = 0.379 for the adjusted comparison of the 3 groups). The hazard ratio of the adjusted comparison between the LEG and the CG was 1.38 (0.83–2.28, p = 0.642) and that between the EEG and the CG was 1.35 (0.81–2.24, p = 0.743).\ud \ud Conclusions: After considerably interfering with exposure during the first year of life, there was a trend towards a higher risk of malaria in the second year in children who had received chemoprophylaxis, but there was no significant rebound. No evidence was found that the age of first exposure to malaria affects the rate of acquisition of NAI. Thus, the timing of administration of antimalarial interventions like malaria vaccines during infancy does not appear to be a critical determinant

Challenges in the diagnosis of iron deficiency in children exposed to high prevalence of infections.

BACKGROUND: While WHO guidelines recommend iron supplements to only iron-deficient children in high infection pressure areas, these are rarely implemented. One of the reasons for this is the commonly held view that iron supplementation increases the susceptibility to some infectious diseases including malaria. Secondly, currently used markers to diagnose iron deficiency are also modified by infections. With the objective of improving iron deficiency diagnosis and thus, its management, we evaluated the performance of iron markers in children exposed to high infection pressure. METHODOLOGY/PRINCIPAL FINDINGS: Iron markers were compared to bone marrow findings in 180 anaemic children attending a rural hospital in southern Mozambique. Eighty percent (144/180) of the children had iron deficiency by bone marrow examination, 88% (155/176) had an inflammatory process, 66% (119/180) had moderate anaemia, 25% (45/180) severe anaemia and 9% (16/180) very severe anaemia. Mean cell haemoglobin concentration had a sensitivity of 51% and specificity of 71% for detecting iron deficiency. Soluble transferrin receptor (sTfR) and soluble transferrin receptor/log ferritin (TfR-F) index (adjusted by C reactive protein) showed the highest areas under the ROC curve (AUC(ROC)) (0.75 and 0.76, respectively), and were the most sensitive markers in detecting iron deficiency (83% and 75%, respectively), but with moderate specificities (50% and 56%, respectively). CONCLUSIONS/SIGNIFICANCE: Iron deficiency by bone marrow examination was extremely frequent in these children exposed to high prevalence of infections. However, even the best markers of bone marrow iron deficiency did not identify around a quarter of iron-deficient children. Tough not directly extrapolated to the community, these findings urge for more reliable, affordable and easy to measure iron indicators to reduce the burden of iron deficiency anaemia in resource-poor settings where it is most prevalent

Plasmodium falciparum-Specific Cellular Immune Responses after Immunization with the RTS,S/AS02D Candidate Malaria Vaccine in Infants Living in an Area of High Endemicity in Mozambique ▿

Results from clinical trials in areas where malaria is endemic have shown that immunization with RTS,S/AS02A malaria vaccine candidate induces partial protection in adults and children and cellular effector and memory responses in adults. For the first time in a malaria vaccine trial, we sought to assess the cell-mediated immune responses to RTS,S antigen components in infants under 1 year of age participating in a clinical phase I/IIb trial of RTS,S/AS02D in Mozambique. Circumsporozoite protein (CSP)-specific responses were detected in approximately half of RTS,S-immunized infants and included gamma interferon (IFN-γ), interleukin-2 (IL-2), and combined IL-2/IL-4 responses. The median stimulation indices of cytokine-producing CD4+ and CD8+ cells were very low but significantly higher in RTS,S-immunized infants than in infants that received the comparator vaccine. Protection against subsequent malarial infection tended to be associated with a higher percentage of individuals with CSP-specific IL-2 in the supernatant (P = 0.053) and with higher CSP-specific IFN-γ-producing CD8+ T-cell responses (P = 0.07). These results report for the first time the detection of malaria-specific cellular immune responses after vaccination of infants less than 1 year of age and pave the way for future field studies of cellular immunity to malaria vaccine candidates

Receiver operating characteristic curves of the iron markers in the identification of iron stores deficiency.

<p>Cut-off values for sTfR and TfR-F index with the highest sensitivity to detect iron deficiency maintaining the specificity≥50% are indicated with arrows. Abbreviations: Sat. Transf., transferrin saturation; sTfR, soluble transferrin receptor; TfR-F index, transferrin-ferritin index; TIBC, total iron binding capacity.</p

Sensitivity, specificity and accuracy of internationally accepted cut-off values of iron markers to identify iron stores deficiency using bone marrow iron content as “gold standard”.

1<p>By C reactive protein (CRP): <12 ng/ml if CRP<1 mg/dl, and <30 ng/ml if CRP≥1 mg/dl.</p>2<p>By age: <50 ng/ml in children 3–5 months of age, and <7 ng/ml in children >5 months of age.</p>3<p>By CRP: >1.5 if CRP<1 mg/dl, and >0.8 if CRP≥1 mg/dl.</p>4<p>By age: <70 fl in children<2 years of age, and <73 fl in children ≥2 years of age.</p><p>Abbreviations: MCHC, mean cell haemoglobin concentration; MCV, mean cell volume; Neg, negative; Pos, positive; sTfR, soluble transferrin receptor; TfR-F index, transferrin-ferritin index; TIBC, total iron binding capacity.</p

Demographic and clinical characteristics of the study participants.

*<p>Arithmetic Mean (SD).</p><p>N = 180 and results expressed as n (%) unless otherwise indicated.</p><p>Abbreviations: HAZ, height for age Z score; Hb, haemoglobin; HIV, human immunodeficiency virus; WAZ, weight for age Z score.</p