Fernando Sempértegui

Assessment of the Binax NOW Streptococcus pneumoniae Urinary Antigen Test in Children with Nasopharyngeal Pneumococcal Carriage

We evaluated the Binax NOW Streptococcus pneumoniae urinary antigen assay by testing 210 healthy children aged 2--60 months living in urban slums of Quito, Ecuador. Healthy children with nasopharyngeal carriage of S. pneumoniae were significantly more likely to have positive urinary antigen test results than were children who were not carriers (30 of 138 vs. 3 of 71 children; chi2=10.8; P<.001). The rate of nasopharyngeal carriage of S. pneumoniae decreased with increasing age; the lowest rates were found in children with the worst nutritional status.

Chloramphenicol versus ampicillin plus gentamicin for community acquired very severe pneumonia among children aged 2-59 months in low resource settings: multicentre randomised controlled trial (SPEAR study)

Objective To evaluate whether five days’ treatment with injectable ampicillin plus gentamicin compared with chloramphenicol reduces treatment failure in children aged 2-59 months with community acquired very severe pneumonia in low resource settings. Design Open label randomised controlled trial. Setting Inpatient wards within tertiary care hospitals in Bangladesh, Ecuador, India, Mexico, Pakistan, Yemen, and Zambia. Participants Children aged 2-59 months with WHO defined very severe pneumonia. Intervention Chloramphenicol versus a combination of ampicillin plus gentamicin. Main outcome measures Primary outcome measure was treatment failure at five days. Secondary outcomes were treatment failure defined similarly among all participants evaluated at 48 hours and at 10 and 21 days. Results More children failed treatment with chloramphenicol at day 5 (16% v 11%; relative risk 1.43, 95% confidence interval 1.03 to 1.97) and also by days 10 and 21. Overall, 112 bacterial isolates were obtained from blood and lung aspirates in 110 children (11.5%), with the most common organisms being Staphylococcus aureus (n=47) and Streptococcus pneumoniae (n=22). In subgroup analysis, bacteraemia with any organism increased the risk of treatment failure at 21 days in the chloramphenicol group (2.09, 1.41 to 3.10) but not in the ampicillin plus gentamicin group (1.12, 0.59 to 2.13). Similarly, isolation of S pneumoniae increased the risk of treatment failure at day 21 (4.06, 2.73 to 6.03) and death (5.80, 2.62 to 12.85) in the chloramphenicol group but not in the ampicillin plus gentamicin group. No difference was found in treatment failure for children with S aureus bacteraemia in the two groups, but the power to detect a difference in this subgroup analysis was low. Independent predictors of treatment failure by multivariate analysis were hypoxaemia (oxygen saturation <90%), receiving chloramphenicol, being female, and poor immunisation status. Conclusion Injectable ampicillin plus gentamicin is superior to injectable chloramphenicol for the treatment of community acquired very severe pneumonia in children aged 2-59 months in low resource settings. Trial registration Current Controlled Trials ISRCTN39543942.

Safety, immunogenicity and protective effect of the SPf66 malaria synthetic vaccine against Plasmodium falciparum infection in a randomized double-blind placebo-controlled field trial in an endemic area of Ecuador.

A total of 537 subjects were randomized to receive either SPf66 malaria vaccine against Plasmodium falciparum or placebo in three doses (days 0, 30 and 180). Subjects completing the course of vaccination (230 in the vaccine and 238 in the placebo group) were followed up for a further 12 months. Case detection surveillance was implemented by parasitological cross-sectional surveys every 2 months and by monthly household visits to each participant. Symptomatic subjects were also diagnosed in a local health centre. Minor local side-effects were observed mainly after the second dose in about 19% of the vaccinated subjects and in 3.7% of the placebo group. Thirty days after the third dose the prevalence of anti-SPf66 antibodies was 57% in the vaccine and 8.8% in the placebo groups. The prevaccination prevalence of antibodies measured by indirect immunofluorescence assay increased with age and seemed to be inversely related to anti-SPf66 antibody production. Immune response to SPf66 was independent of age. Vaccine efficacy was calculated based on person-time of exposure. The protective effect considering any malaria episode was 66.8% (95% confidence interval = -2.7-89.3%) and considering only one episode per individual was 60.2% (95% confidence interval = -26-87.5%).

Micronutrient Deficiencies Are Associated with Impaired Immune Response and Higher Burden of Respiratory Infections in Elderly Ecuadorians

The proportion of the Latin American population above age 65 y is expected to rise substantially. To better define the prevalence of infectious diseases and micronutrient deficiencies, assess immunological status, and evaluate associations between nutritional status and infection, we performed a cross-sectional study of elderly Ecuadorians in a low-income peri-urban community in Quito, Ecuador. Culturally adapted questionnaires, delayed type hypersensitivity (DTH) skin response, micronutrient, and immunological assays were performed in randomly selected Ecuadorians aged > or = 65 y. Multiple linear and logistic regression models were developed to assess relationships between micronutrient concentrations and history of infection, DTH, and immune function. Participants (n = 352; mean age +/- SD, 74.4 +/- 6.4 y) recalled recent episodes of colds/influenza-like syndromes (62.8%), cough (61.0%), urinary tract infection (37.9%), diarrhea (32.2%), fever (24.1%), and pneumonia (3.5%). A prospective substudy of respiratory infections (RI) in 203 elderly revealed similar findings. Colds and pneumonia occurred in 42.8 and 7.9% of participants, respectively, during 737 person-weeks of observation (3.6 +/- 1.1 wk per person). Anemia and micronutrient deficiencies, especially for vitamins C, D, B-6, and B-12 and folic acid and zinc, were common. Plasma vitamin C was associated with interferon-gamma (IFNgamma) (P < 0.01) and zinc with IFNgamma and interleukin-2 (each P < 0.0001). RI history was associated with any micronutrient deficiency (P < 0.001). The burden of infectious diseases, micronutrient deficiencies, and anemia was substantial in this elderly Ecuadorian population. Deficiencies of essential vitamins and minerals place these elderly adults at risk for infections through their negative impact on immune function.

Metabolic syndrome in the elderly living in marginal peri-urban communities in Quito, Ecuador

OBJECTIVEnThe proportion of the Latin American population aged >60 years is expected to double during the next few decades. Metabolic syndrome (MetS) is associated with high morbidity and mortality worldwide. However, little is known about MetS in Latin America in general, and in Ecuador in particular. The present study aimed to examine the prevalence of MetS and its association with blood micronutrient, homocysteine (Hcy) and C-reactive protein (CRP) concentrations in the elderly living in a low-income urban area.nnnDESIGNnWe performed a cross-sectional study. MetS, using the International Diabetes Federation definition, dietary intake and plasma micronutrient, CRP and Hcy concentrations were assessed.nnnSUBJECTSnA total of 352 elderly (≥65 years) Ecuadorians.nnnSETTINGnQuito, Ecuador.nnnRESULTSnMetS was prevalent (40%)--considerably more so among women (81%) than men (19%; χ² = 32·6, P < 0·0001). Further, 53 % of those without MetS exhibited two or more of its components. Micronutrient deficiencies were prevalent, including those of vitamin C, zinc, vitamin B₁₂ and folate. Vitamin C and E concentrations were inversely (OR = 0·78, 95% CI 0·71, 0·86; OR = 0·16, 95% CI 0·03, 0·81, respectively) and CRP (OR = 1·79, 95 % CI 1·04, 3·06) was positively associated with MetS.nnnCONCLUSIONSnThe coexistence of MetS with micronutrient deficiencies suggests that elderly Ecuadorians suffer from the double burden of diseases that are increasingly being observed in less developed countries. More research is needed to determine the causal factors, but results presented suggest that these older adults would benefit from interventions to reduce the risk factors for MetS, in particular higher consumption of micronutrient-rich foods.

Air pollution and anemia as risk factors for pneumonia in Ecuadorian children: a retrospective cohort analysis.

BackgroundAmbient air pollution and malnutrition, particularly anemia, are risk factors for pneumonia, a leading cause of death in children under five. We simultaneously assessed these risk factors in Quito, Ecuador.MethodsIn 2005, we studied two socioeconomically similar neighborhoods in Quito: Lucha de los Pobres (LP) and Jaime Roldos (JR). LP had relatively high levels of air pollution (annual median PM2.5 = 20.4 μg/m3; NO2 = 29.5 μg/m3) compared to JR (annual median PM2.5 = 15.3 μg/m3; NO2 = 16.6 μg/m3). We enrolled 408 children from LP (more polluted) and 413 children from JR (less polluted). All subjects were aged 18-42 months. We obtained medical histories of prior physician visits and hospitalizations during the previous year, anthropometric nutrition data, hemoglobin levels, and hemoglobin oxygen saturation via oximetry.ResultsIn anemic children, higher pollution exposure was significantly associated with pneumonia hospitalization (OR = 6.82, 95%CI = 1.45-32.00; P = 0.015). In non-anemic children, no difference in hospitalizations by pollution exposure status was detected (OR = 1.04, NS). Children exposed to higher levels of air pollution had more pneumonia hospitalizations (OR = 3.68, 1.09-12.44; P = 0.036), total respiratory illness (OR = 2.93, 95% CI 1.92-4.47; P < 0.001), stunting (OR = 1.88, 1.36-2.60; P < 0.001) and anemia (OR = 1.45, 1.09-1.93; P = 0.013) compared to children exposed to lower levels of air pollution. Also, children exposed to higher levels of air pollution had significantly lower oxygen saturation (92.2% ± 2.6% vs. 95.8% ± 2.2%; P < 0.0001), consistent with air pollution related dyshemoglobinemia.ConclusionsAmbient air pollution is associated with rates of hospitalization for pneumonia and with physicians consultations for acute respiratory infections. Anemia may interact with air pollution to increase pneumonia hospitalizations. If confirmed in larger studies, improving nutrition-related anemia, as well as decreasing the levels of air pollution in Quito, may reduce pneumonia incidence.

Emergency room visits for respiratory conditions in children increased after Guagua Pichincha volcanic eruptions in April 2000 in Quito, Ecuador observational study: time series analysis.

BackgroundThis study documented elevated rates of emergency room (ER) visits for acute upper and lower respiratory infections and asthma-related conditions in the children of Quito, Ecuador associated with the eruption of Guagua Pichincha in April of 2000.MethodsWe abstracted 5169 (43% females) ER records with primary respiratory conditions treated from January 1 – December 27, 2000 and examined the change in pediatric ER visits for respiratory conditions before, during, and after exposure events of April, 2000. We applied a Poisson regression model adapted to time series of cases for three non-overlapping disease categories: acute upper respiratory infection (AURI), acute lower respiratory infection (ALRI), and asthma-related conditions in boys and girls for three age groups: 0–4, 5–9, and 10–15 years.ResultsAt the main pediatric medical facility, the Baca Ortiz Pediatric Hospital, the rate of emergency room (ER) visits due to respiratory conditions substantially increased in the three weeks after eruption (RR = 2.22, 95%CI = [1.95, 2.52] and RR = 1.72 95%CI = [1.49, 1.97] for lower and upper respiratory tract infections respectively. The largest impact of eruptions on respiratory distress was observed in children younger than 5 years (RR = 2.21, 95%CI = [1.79, 2.73] and RR = 2.16 95%CI = [1.67, 2.76] in boys and girls respectively). The rate of asthma and asthma-related diagnosis doubled during the period of volcano fumarolic activity (RR = 1.97, 95%CI = [1.19, 3.24]). Overall, 28 days of volcanic activity and ash releases resulted in 345 (95%CI = [241, 460]) additional ER visits due to respiratory conditions.ConclusionThe study has demonstrated strong relationship between ash exposure and respiratory effects in children.

Setting priorities for zinc-related health research to reduce children's disease burden worldwide: an application of the Child Health and Nutrition Research Initiative's research priority-setting method.

OBJECTIVEnTo make the best use of limited resources for supporting health-related research to reduce child mortality, it is necessary to apply a suitable method to rank competing research options. The Child Health and Nutrition Research Initiative (CHNRI) developed a new methodology for setting health research priorities. To broaden experience with this priority-setting technique, we applied the method to rank possible research priorities concerning the control of Zn deficiency. Although Zn deficiency is not generally recognized as a direct cause of child mortality, recent research indicates that it predisposes children to an increased incidence and severity of several of the major direct causes of morbidity and mortality.nnnDESIGNnLeading experts in the field of Zn research in child health were identified and invited to participate in a technical working group (TWG) to establish research priorities. The individuals were chosen to represent a wide range of expertise in Zn nutrition. The seven TWG members submitted a total of ninety research options, which were then consolidated into a final list of thirty-one research options categorized by the type of resulting intervention.nnnRESULTSnThe identified priorities were dominated by research investment options targeting Zn supplementation, and were followed by research on Zn fortification, general aspects of Zn nutrition, dietary modification and other new interventions.nnnCONCLUSIONSnIn general, research options that aim to improve the efficiency of an already existing intervention strategy received higher priority scores. Challenges identified during the implementation of the methodology and suggestions to modify the priority-setting procedures are discussed.

Spatial and temporal variations and mobile source emissions of polycyclic aromatic hydrocarbons in Quito, Ecuador.

Motor vehicles are a major source of air pollution in Quito, Ecuador; however, little work has been done to characterize spatial and temporal variations in traffic-related pollutants, or to measure pollutants in vehicle emissions. We measured PAH continuously for one year at two residential sites in Quito, and PAH and traffic patterns for one week near a busy roadway. Morning rush-hour traffic and temperature inversions caused daily PAH maxima between 06:00 and 08:00. SO2, NOx, CO, and PM(2.5) behaved similarly. At the residential sites PAH levels during inversions were 2-3-fold higher than during the afternoon, and 10-16-fold higher than 02:00-03:00 when levels were lowest. In contrast, at the near-roadway site, PAH concentrations were 3-6-fold higher than at the residential sites, and the effects of inversions were less pronounced. Cars and buses accounted for >95% of PAH at the near-roadway site. Near-roadway PAH concentrations were comparable to other polluted cities.

Low Concentrations of Zinc in Gastric Mucosa are Associated with Increased Severity of Helicobacter pylori-Induced Inflammation

Background:u2002 Chronic Helicobacter pylori infection is the most common cause of gastric cancer. H. pylori induces oxidative stress while zinc deficiency results in increased sensitivity to it. In Ecuador, the prevalence of gastric cancer and zinc deficiency are high. We hypothesized that zinc deficiency in Ecuadorian people would cause increased H. pylori‐induced inflammation in the gastric mucosa associated with lower tissue zinc concentrations.