Phase I safety and immunogenicity trial of Plasmodium vivax CS derived long synthetic peptides adjuvanted with montanide ISA 720 or montanide ISA 51.

We assessed the safety, tolerability, and immunogenicity of a mixture of three synthetic peptides derived from the Plasmodium vivax circumsporozoite protein formulated in Montanide ISA 720 or Montanide ISA 51. Forty healthy malaria-naive volunteers were allocated to five experimental groups (A-E): four groups (A-D) were immunized intramuscularly with 50 and 100 µg/dose injections of a mixture of N, R, and C peptides formulated in the two different adjuvants at 0, 2, and 4 months and one group was administered placebo. Vaccines were immunogenic, safe, well tolerated, and no serious adverse events related to the vaccine occurred. Seroconversion occurred in > 90% of the vaccines and antibodies recognized the sporozoite protein on immunofluorescent antibody test. Vaccines in Montanide ISA 51 showed a higher sporozoite protein recognition and interferon production. Results encourage further testing of the vaccine protective efficacy.

Prevalence of rheumatic heart disease in children and young adults in Nicaragua.

Rheumatic heart disease (RHD) results in morbidity and mortality that is disproportionate among individuals in developing countries compared to those living in economically developed countries. The global burden of disease is uncertain because most previous studies to determine the prevalence of RHD in children relied on clinical screening criteria that lacked the sensitivity to detect most cases. The present study was performed to determine the prevalence of RHD in children and young adults in León, Nicaragua, an area previously thought to have a high prevalence of RHD. This was an observational study of 3,150 children aged 5 to 15 years and 489 adults aged 20 to 35 years randomly selected from urban and rural areas of León. Cardiopulmonary examinations and Doppler echocardiographic studies were performed on all subjects. Doppler echocardiographic diagnosis of RHD was based on predefined consensus criteria that were developed by a working group of the World Health Organization and the National Institutes of Health. The overall prevalence of RHD in children was 48 in 1,000 (95% confidence interval 35 in 1,000 to 60 in 1,000). The prevalence in urban children was 34 in 1,000, and in rural children it was 80 in 1,000. Using more stringent Doppler echocardiographic criteria designed to diagnose definite RHD in adults, the prevalence was 22 in 1,000 (95% confidence interval 8 in 1,000 to 37 in 1,000). In conclusion, the prevalence of RHD among children and adults in this economically disadvantaged population far exceeds previously predicted rates. The findings underscore the potential health and economic burden of acute rheumatic fever and RHD and support the need for more effective measures of prevention, which may include safe, effective, and affordable vaccines to prevent the streptococcal infections that trigger the disease.

Meeting the needs of adolescent post-abortion care patients in the Dominican Republic.

Counselling on contraception and contraceptive method provision are key components of post-abortion care (PAC). Some studies have suggested that adolescent PAC patients receive worse care than older women seeking these services. This study aimed to evaluate an intervention whose goal was to improve the counselling and contraceptive uptake of PAC patients, with special attention given to the needs of adolescent patients, in the four public hospitals in the Dominican Republic where PAC services were not being routinely offered. The counselling intervention effort included provider training and the development of adolescent-friendly information, education and communication (IEC) materials. Eighty-eight providers were interviewed at baseline and 6 months after the intervention was implemented. Six months after providers were trained, 140 adolescent PAC patients (< or = 19 years of age) and 134 older PAC patients (20-35 years) were interviewed about the contraceptive counselling messages and contraceptive methods they received before they were discharged from hospital. The adolescent and older PAC patients were matched on study hospital and time of arrival. Significant improvements were noted in provider knowledge and attitudes. No changes were noted in provider-reported PAC counselling behaviours, with close to 70% of providers reporting they routinely assess patients' fertility intentions, discuss contraception, assess STI/HIV risk and discuss post-abortion complications. Adolescent and older PAC patients reported receiving PAC counselling messages at similar rates. Forty per cent of adolescent PAC patients and 45% of older PAC patients who wanted to delay pregnancy were discharged with a contraceptive method. Adolescents were more likely to receive an injectable contraceptive method whereas older women were discharged with a variety of methods. The PAC counselling intervention increased provider knowledge and improved their attitudes and benefited both adolescent and older patients.

Bridging emergency contraceptive pill users to regular contraception: results from a randomized trial in Jamaica.

BACKGROUND: Emergency contraception research has shifted from examining the public health effects of increasing access to emergency contraceptive pills (ECPs) to bridging ECP users to a regular contraceptive method as a way of decreasing unintended pregnancies. STUDY DESIGN: In a randomized controlled trial in Jamaica, we tested a discount coupon for oral contraceptive pills (OCPs) among pharmacy-based ECP purchasers as an incentive to adopt (i.e., use for at least 2 months) this and other regular contraceptive methods. Women in the intervention and control arms were followed up at 3 and 6 months after ECP purchase to determine whether they adopted the OCP or any other contraceptive method. Condom use was recorded but was not considered a regular contraceptive due to its inconsistent use. RESULTS: There was no significant difference in the proportion of women who adopted the OCP, injectable or intrauterine device in the control group or the intervention group (p=.39), and only 14.6% of the sample (mostly OCP adopters) used one of these three methods. Condom use was high (44.0%), demonstrating that ECP users were largely a condom-using group. CONCLUSIONS: The discount coupon intervention was not successful. Although a small proportion of ECP users did bridge, the coupon did not affect the decision to adopt a regular contraceptive method. The study highlighted the need for bridging strategies to consider women's reproductive and sexual behaviors, as well as their context. However, in countries like Jamaica where HIV/AIDS is of concern and condom use is appropriately high, bridging may not be an optimal strategy.

Successful sporozoite challenge model in human volunteers with Plasmodium vivax strain derived from human donors.

Successful establishment of a Plasmodium vivax sporozoite challenge model in humans is described. Eighteen healthy adult, malaria-naïve volunteers were randomly allocated to Groups A-C and exposed to 3 +/- 1, 6 +/- 1, and 9 +/- 1 bites of Anopheles albimanus mosquitoes infected with P. vivax, respectively. Seventeen volunteers developed signs and symptoms consistent with malaria, and geometric mean prepatent periods of 11.1 days (9.3-11) for Group A; 10.8 days (9.8-11.9) for Group B; and 10.6 days (8.7-12.4) for Group C, with no statistically significant difference among groups (Kruskal-Wallis, P = 0.70). One volunteer exposed to eight mosquito bites did not develop a parasitemia. No differences in parasite density were observed and all individuals successfully recovered after anti-malarial treatment. None of the volunteers developed parasite relapses within an 18-month follow-up. In conclusion, malaria-naive volunteers can be safely and reproducibly infected with bites of 2-10 An. albimanus mosquitoes carrying P. vivax sporozoites. This challenge method is suitable for vaccine and anti-malarial drug testing.

Safety and elicitation of humoral and cellular responses in colombian malaria-naive volunteers by a Plasmodium vivax circumsporozoite protein-derived synthetic vaccine.

Substantial experimental evidence indicates that the Plasmodium circumsporozoite (CS) protein has great potential as a vaccine candidate. We tested the safety and immunogenicity of vaccines composed of P. vivax CS-derived synthetic peptides. Sixty-nine healthy, malaria-naive volunteers were randomized to receive three injections of placebo or synthetic proteins N, R, or C (10, 30, or 100 microg/dose) in a double-blinded fashion. Vaccines were well tolerated and no serious adverse events were observed. Peptides N and R elicited humoral responses at all doses; peptide C elicicted these responses only at doses of 30 and 100 microg. The N peptide at a dose of 100 microg elicited the greatest antibody response. Antibodies to the three peptides recognized P. vivax sporozoites in an immunofluorescent antibody test. Peripheral blood mononuclear cells from most immunized volunteers also produced interferon-gamma upon peptide in vitro stimulation. These vaccines appear safe, well tolerated, and immunogenic in malaria-naive volunteers. Further optimization and development of this vaccine is being attempted to conduct phase II clinical trials.

Psychosocial aspects of Costa Rican adolescents' eating and physical activity patterns.

PURPOSE: To determine the importance of some psychosocial aspects on the eating and physical activity patterns of Costa Rican adolescents. METHODS: A total of 1200 adolescents were included in the study. Data were collected using a self-administered instrument containing the following elements: questions to elicit demographic information and five sections with several items (stated as positive or negative behaviors) to study the influence of peers, parents, social environment, body image, and self-efficacy on five target behaviors, intake of foods rich in saturated fats, calcium, and iron, along with consumption of fruits and vegetables and physical activity practices. Data were analyzed using a factor analysis with main component extraction and varimax rotation, along with multiple regression analyses. RESULTS: Social environment and peer influence were the major factors that predict behaviors associated with the intake of foods rich in saturated fat. Meanwhile, parental and social environment influences were the main factors in explaining the fruit and vegetable intake-related behaviors. Self-efficacy was a significant predictor of behaviors associated with physical activity. Body image influence was an important variable associated with all the behaviors analyzed. Multiple regression analyses suggest that the fathers' educational level, the adolescents' age, being female, and living in a rural area may have positive influence on the behaviors studied; however, the overall R(2) for all regression models was quite small (<.03). CONCLUSIONS: Most of the variability in adolescents' food intake and physical activity-related behaviors remained unexplained by the demographic variables included in the study. Nevertheless, the results suggest that promotion of health programs built on the influence of social environment, peers and family members, and self-efficacy may have a positive impact on the adolescents' food and physical activity patterns. However, the clear definition of which psychosocial aspect(s) strongly influence the behavior to be modified, is essential for designing an intervention that is properly directed at the correct target.