IgG subclass responses to excreted-secreted antigens of Plasmodium falciparum in a low-transmission malaria area of the Peruvian Amazon.

BACKGROUND: Malaria in Peru is concentrated in the Amazon region, especially in Loreto, and transmission is focused in rural and peri-urban communities. The government has approved a malaria elimination plan with a community approach and seeks to reduce the risk of transmission through preventive interventions, but asymptomatic and low-parasite-density infections are challenges for disease control and elimination. IgG antibodies play a critical role in combating infection through their ability to reduce parasitaemia and clinical symptoms. In particular, IgG subclasses have important roles in controlling malaria disease and may provide new insight into the development of malaria control strategies and understanding of malaria transmission. Through the use of excreted-secreted antigens from Plasmodium falciparum, were evaluated the responses of the four IgG subclasses in symptomatic and asymptomatic malarial infections. RESULTS: Higher levels of whole IgG were observed in asymptomatic carriers (P < 0.05). IgG3 and IgG1 were the most prevalent subclasses and did not show differences in their antibody levels in either type of carrier. All symptomatic carriers were positive for IgG4, and the presence of IgG3 and IgG2 were correlated with protection against parasitaemia. IgG2 showed lower prevalence and antibody titers in comparison to other subclasses. CONCLUSIONS: This is the first study that characterizes the IgG subclass response in the Peruvian Amazon, and these results show that even in populations from regions with low malaria transmission, a certain degree of naturally acquired immunity can develop when the right antibody subclasses are produced. This provides important insight into the potential mechanisms regulating protective immunity.

A Double-Blind Randomized Controlled Trial of Maternal Postpartum Deworming to Improve Infant Weight Gain in the Peruvian Amazon.

BACKGROUND: Nutritional interventions targeting the critical growth and development period before two years of age can have the greatest impact on health trajectories over the life course. Compelling evidence has demonstrated that interventions investing in maternal health in the first 1000 days of life are beneficial for both mothers and their children. One such potential intervention is deworming integrated into maternal postpartum care in areas where soil-transmitted helminth (STH) infections are endemic. METHODOLOGY/PRINCIPAL FINDINGS: From February to August 2014, 1010 mother-infant pairs were recruited into a trial aimed at assessing the effectiveness of maternal postpartum deworming on infant and maternal health outcomes. Following delivery, mothers were randomly assigned to receive either single-dose 400 mg albendazole or placebo. Participants were followed-up at 1 and 6 months postpartum. There was no statistically significant difference in mean weight gain between infants in the experimental and control groups (mean difference: -0.02; 95% CI: -0.1, 0.08) at 6 months of age. Further, deworming had no effect on measured infant morbidity indicators. However, ad hoc analyses restricted to mothers who tested positive for STHs at baseline suggest that infants of mothers in the experimental group had greater mean length gain in cm (mean difference: 0.8; 95% CI: 0.1, 1.4) and length-for-age z-score (mean difference: 0.5; 95% CI: 0.2, 0.8) at 6 months of age. CONCLUSIONS/SIGNIFICANCE: In a study population composed of both STH-infected and uninfected mothers, maternal postpartum deworming was insufficient to impact infant growth and morbidity indicators up to 6 months postpartum. Among STH-infected mothers, however, important improvements in infant length gain and length-for-age were observed. The benefits of maternal postpartum deworming should be further investigated in study populations having higher overall prevalences and intensities of STH infections and, in particular, where whipworm and hookworm infections are of public health concern. TRIAL REGISTRATION: ClinicalTrials.gov (NCT01748929).

Epidemiology of Plasmodium vivax Malaria in Peru.

Malaria in Peru, dominated by Plasmodium vivax, remains a public health problem. The 1990s saw newly epidemic malaria emerge, primarily in the Loreto Department in the Amazon region, including areas near to Iquitos, the capital city, but sporadic malaria transmission also occurred in the 1990s-2000s in both north-coastal Peru and the gold mining regions of southeastern Peru. Although a Global Fund-supported intervention (PAMAFRO, 2005-2010) was temporally associated with a decrease of malaria transmission, from 2012 to the present, both P. vivax and Plasmodium falciparum malaria cases have rapidly increased. The Peruvian Ministry of Health continues to provide artemesinin-based combination therapy for microscopy-confirmed cases of P. falciparum and chloroquine-primaquine for P. vivax Malaria transmission continues in remote areas nonetheless, where the mobility of humans and parasites facilitates continued reintroduction outside of ongoing surveillance activities, which is critical to address for future malaria control and elimination efforts. Ongoing P. vivax research gaps in Peru include the following: identification of asymptomatic parasitemics, quantification of the contribution of patent and subpatent parasitemics to mosquito transmission, diagnosis of nonparasitemic hypnozoite carriers, and implementation of surveillance for potential emergence of chloroquine- and 8-aminoquinoline-resistant P. vivax Clinical trials of tafenoquine in Peru have been promising, and glucose-6-phosphate dehydrogenase deficiency in the region has not been observed to be a limitation to its use. Larger-scale challenges for P. vivax (and malaria in general) in Peru include logistical difficulties in accessing remote riverine populations, consequences of government policy and poverty trends, and obtaining international funding for malaria control and elimination.

[Congenital malaria in a hospital in Iquitos, Peru]. / Malaria congénita en un hospital de iquitos, Perú.

OBJECTIVES: To determine the frequency and clinical features of newborns with congenital malaria in the Hospital de Apoyo of Iquitos in the Peruvian Amazon. MATERIALS AND METHODS: Descriptive, prospective and cross-sectional study. From January 2011 to December 2013, 14.017 newborns and their mothers were studied, of whom 52 carriers of gestational malaria were selected while their infants were hospitalized in the Neonatology Unit, and underwent clinical assessment and laboratory studies. RESULTS: Gestational malaria frequency was 0.4% and a proportion of 9.6% of congenital malaria. Plasmodium vivax was found in 80% of cases of gestational malaria and in 60% of congenital malaria. A case of fetal death with positive thick blood smear for Plasmodium falciparum was observed. The clinical presentation in newborns was fever, hypoactivity, irritability and poor suction. CONCLUSIONS: The presence of congenital malaria in infants born to mothers with gestational malaria is documented. The clinical picture resembled neonatal sepsis. Early diagnosis of congenital malaria and timely treatment present with good evolution.

Malaria congénita en un hospital de Iquitos, Perú / Congenital malaria in a hospital in Iquitos, Peru

Objetivos. Determinar la frecuencia y características clínicas de los recién nacidos con malaria congénita en el Hospital de Apoyo de Iquitos en la Amazonía peruana. Materiales y métodos. Estudio descriptivo, prospectivo y transversal. De enero de 2011 a diciembre de 2013 se estudiaron 14 017 recién nacidos y a sus madres, de quienes se seleccionaron 52 portadoras de malaria gestacional mientras que a sus recién nacidos se les hospitalizó en el Servicio de Neonatología del hospital, y fueron sometidos a evaluación clínica y estudios de laboratorio. Resultados. La frecuencia de malaria gestacional fue de 0,4% y una proporción de malaria congénita de 9,6%. Plasmodium vivax fue hallado en 80% de casos de malaria gestacional y en 60% de malaria congénita. Se observó un caso de óbito fetal con gota gruesa positiva para Plasmodium falciparum. El cuadro clínico en recién nacidos fue fiebre, hipoactividad, irritabilidad y pobre succión. Conclusiones. Se documenta la presencia de malaria congénita en recién nacidos de madres con malaria gestacional. El cuadro clínico se asemeja a una sepsis neonatal. El diagnóstico precoz de malaria congénita y el tratamiento oportuno cursan con buena evolución.

Objectives. To determine the frequency and clinical features of newborns with congenital malaria in the Hospital de Apoyo of Iquitos in the Peruvian Amazon. Materials and methods. Descriptive, prospective and cross-sectional study. From January 2011 to December 2013, 14.017 newborns and their mothers were studied, of whom 52 carriers of gestational malaria were selected while their infants were hospitalized in the Neonatology Unit, and underwent clinical assessment and laboratory studies. Results. Gestational malaria frequency was 0.4% and a proportion of 9.6% of congenital malaria. Plasmodium vivax was found in 80% of cases of gestational malaria and in 60% of congenital malaria. A case of fetal death with positive thick blood smear for Plasmodium falciparum was observed. The clinical presentation in newborns was fever, hypoactivity, irritability and poor suction. Conclusions. The presence of congenital malaria in infants born to mothers with gestational malaria is documented. The clinical picture resembled neonatal sepsis. Early diagnosis of congenital malaria and timely treatment present with good evolution.

Síndrome de abdomen en ciruela pasa y dextrocardia, asociación infrecuente / Prune belly syndrome and dextrocardia, an infrequent association

Se describe un neonato con Síndrome de abdomen en ciruela pasa, de sexo masculino, nacido de 36 semanas de gestación y pesó 3 650 g al nacer. El examen clínico mostró un neonato con un abdomen globuloso, con redundancia de la piel que huelga a los costados rebosantes, la palpación del abdomen no descubre la tonalidad muscular. No se palpa visceromegalia y hay presencia normal de ruidos hidroaéreos. El examen físico del tórax y cardiovascular fueron aparentemente normales. Normocéfalo y facies no peculiar. La radiografía de tórax muestra dextrocardía. La ecografía renal mostró dilatación pielocalicial. Revela además criptorquidia bilateral. (AU)

We report the case of a male neonate born after 36 weeks of gestation with a body weight of 3 650 g with Prune belly Syndrome. The physical examination revealed a distended abdomen with redundant skin that wrinkle like a prune, no visceromegaly was found and normal abdominal sounds were heard. The examination of thorax and cardiovascular systems were apparently normal. The neurologic exam was normal. The chest x-ray revealed dextrocardia. A renal ultrasound revealed pyelocalyceal dilation. Bilateral cryptorchidism was also observed. (AU)

Timing of umbilical cord-clamping and infant anaemia: the role of maternal anaemia.

BACKGROUND: Evidence from randomized controlled trials has shown that delayed cord-clamping is beneficial to infant iron status. The role of maternal anaemia in this relationship, however, has not been established. OBJECTIVE: To determine the effect of maternal anaemia at delivery on the association between timing of umbilical cord-clamping and infant anaemia at 4 and 8 months of age. METHODS: A cohort of pregnant women admitted to the labour room of Hospital Iquitos (Iquitos, Peru) and their newborns were recruited into the study during two time periods (18 May to 3 June and 6-20 July 2009). Between the two recruitment periods, the hospital's policy changed from early to delayed umbilical cord-clamping. Maternal haemoglobin levels were measured before delivery, and the time between delivery and cord-clamping was recorded at delivery for the entire cohort. Mother-infant pairs were followed-up at 4 (n = 207) and 8 months (n = 184) post partum. Infant haemoglobin levels were measured at follow-up visits. Data were analysed using logistic regression models. RESULTS: The prevalence of maternal anaemia (Hb <11.0 g/dl) at delivery was 22%. Infant haemoglobin levels at 4 and 8 months of age were 10.4 g/dl and 10.3 g/dl, respectively. Infant haemoglobin levels did not differ significantly between infants born to anaemic mothers and those born to non-anaemic mothers at either 4 or 8 months of age. However, the association between the timing of cord-clamping and infant anaemia was modified by the mother's anaemia status. Significant benefits of delayed cord-clamping in preventing anaemia were found in infants born to anaemic mothers at both 4 months (aOR = 0.59, 95% CI 0.36-0.99) and 8 months (aOR = 0.38, 95% CI 0.19-0.76) of age. CONCLUSION: The study contributes additional evidence in support of delayed cord-clamping. This intervention is likely to have most public health impact in areas with a high prevalence of anaemia during pregnancy.

A hospital policy change toward delayed cord clamping is effective in improving hemoglobin levels and anemia status of 8-month-old Peruvian infants.

OBJECTIVE: To assess the effectiveness of a hospital policy change toward delayed cord clamping on infant hemoglobin (Hb) levels and anemia status at 4 and 8 months of age. METHODS: A cohort of Peruvian mothers and infants, originating from a pre/post study investigating a change in hospital policy from early to delayed cord clamping, was followed until 8 months postpartum. Infant hemoglobin levels and anemia status were measured at 4 and 8 months postpartum. RESULTS: Following the hospital policy change, adjusted mean infant Hb levels improved by 0.89 gdl(-1) [95% confidence interval (95% CI) 0.57-1.22] and anemia was significantly reduced (aOR = 0.38; 95% CI 0.19-0.78) at 8 months postpartum. CONCLUSIONS: A hospital policy change toward delayed cord clamping is effective in improving Hb levels and the anemia status of 8-month-old infants. Prior to scaling-up this intervention, issues related to training, monitoring, safety, additional long-term benefits and specific local conditions should be investigated.

Effect of a two-component intervention to change hospital practice from early to delayed umbilical cord clamping in the Peruvian Amazon.

OBJECTIVE: To investigate the effect of a two-component intervention to change hospital practice with regard to the timing of umbilical cord clamping. METHODS: A pre-/post-study design was used to measure the effect of a two-component intervention on mean time to clamp the umbilical cord. The study took place at Hospital Iquitos "César Garayar García" in Iquitos, Peru. A total of 224 women were recruited from the hospital labor room: 112 pre-intervention, from 18 May-3 June 2009, and 112 post-intervention, from 6-20 July 2009. The intervention consisted of 1) a "best practice" three-day training workshop on birthing, and 2) a hospital directive. All deliveries were observed and the time between delivery of the first shoulder and clamping of the umbilical cord was measured with a digital stopwatch. RESULTS: The mean time between delivery and cord clamping before the intervention was 56.8 seconds (95% confidence interval [CI]: 51.0, 62.7). This increased to 169.8 seconds (95% CI: 153.8, 185.8) following the intervention. The difference in mean time to clamp remained significant in multivariate analyses (ß adjusted = 113.2 seconds, 95% CI: 96.6, 129.9). CONCLUSIONS: Hospital policy and practice can be successfully changed from early to delayed umbilical cord clamping using a simple, two-component intervention.

Effect of a two-component intervention to change hospital practice from early to delayed umbilical cord clamping in the Peruvian Amazon / Efecto de una intervención de dos componentes para modificar la práctica hospitalaria de pinzamiento del cordón umbilical de precoz a tardío en la Amazonia peruana

OBJECTIVE: To investigate the effect of a two-component intervention to change hospital practice with regard to the timing of umbilical cord clamping. METHODS: A pre-/post-study design was used to measure the effect of a two-component intervention on mean time to clamp the umbilical cord. The study took place at Hospital Iquitos "César Garayar García" in Iquitos, Peru. A total of 224 women were recruited from the hospital labor room: 112 pre-intervention, from 18 May-3 June 2009, and 112 post-intervention, from 6-20 July 2009. The intervention consisted of 1) a "best practice" three-day training workshop on birthing, and 2) a hospital directive. All deliveries were observed and the time between delivery of the first shoulder and clamping of the umbilical cord was measured with a digital stopwatch. RESULTS: The mean time between delivery and cord clamping before the intervention was 56.8 seconds (95 percent confidence interval [CI]: 51.0, 62.7). This increased to 169.8 seconds (95 percent CI: 153.8, 185.8) following the intervention. The difference in mean time to clamp remained significant in multivariate analyses (βadjusted = 113.2 seconds, 95 percent CI: 96.6, 129.9). CONCLUSIONS: Hospital policy and practice can be successfully changed from early to delayed umbilical cord clamping using a simple, two-component intervention.

OBJETIVO: Investigar el efecto de una intervención de dos componentes para modificar la práctica hospitalaria respecto del momento en que se practica el pinzamiento del cordón umbilical. MÉTODOS: Se empleó un estudio con diseño antes-después para medir el efecto de una intervención de dos componentes sobre el tiempo medio de pinzamiento del cordón umbilical. El estudio se llevó a cabo en el Hospital Iquitos "César Garayar Gar-cía" en Iquitos (Perú). Se incluyeron en total 224 mujeres atendidas en la sala de trabajo de parto del hospital: 112 antes de la intervención, entre el 18 de mayo y el 3 de junio del 2009, y 112 después de la intervención, entre el 6 y el 20 de julio del 2009. La intervención consistió en: 1) un taller de capacitación sobre las "mejores prácticas" en la atención del parto, de 3 días de duración y 2) una directiva del hospital. Se observaron todos los partos y se midió el tiempo entre la salida del hombro anterior y el pinzamiento del cordón umbilical con un cronómetro digital. RESULTADOS: El tiempo medio entre el parto y el pinzamiento del cordón antes de la intervención fue de 56,8 segundos (intervalo de confianza [IC] de 95 por cento: 51,0-62,7), y aumentó a 169,8 segundos (IC 95 por cento: 153,8-185,8) después de la intervención. La diferencia en el tiempo medio hasta el pinzamiento siguió siendo significativa en los análisis multivariados (βajustado = 113,2 segundos, IC 95 por cento: 96,6-129,9). CONCLUSIONES: Es posible cambiar las normas y las prácticas hospitalarias de pinzamiento del cordón umbilical de precoz a tardío mediante una intervención sencilla de dos componentes.

A comparison of low birth weight among newborns of early adolescents, late adolescents, and adult mothers in the Peruvian Amazon.

To compare low birth weight (LBW: <2,500 g) between infants born to adolescent and adult mothers in Iquitos, Peru. A random sample of 4,467 records of women who delivered at the Hospital Apoyo Iquitos between 2005 and 2007 was collected from hospital birth registries. Multivariate logistic and linear regression analyses were performed to compare LBW in newborns of adolescents (10-14, 15-19 years) and adults (≥20 years) and then for primiparous mothers with a normal gestational age, adjusting for newborn sex, antenatal care, and location of the mother's residence. A total of 4,384 mothers had had a singleton live birth and 1,501 were primiparous with a normal gestational age. Early and late adolescents had significantly greater odds of having a LBW infant than adults (OR = 2.28, 95%CI: 1.09, 4.78; OR = 1.67, 95%CI: 1.30, 2.14, respectively). For primiparous mothers with a normal gestational age, the same was true only for early adolescents (OR = 3.07, 95%CI: 1.09, 8.61). There were significant differences in mean birth weight between adults (3178.7 g) and both adolescent age groups overall (10-14 years: 2848.9 g; 15-19 years: 2998.3 g) and for primiparous mothers with a normal gestational age (10-14 years: 2900.8 g; 15-19 years: 3059.2 g; ≥20 years: 3151.8 g). Results suggest there is an important difference between adolescent and adult mothers in terms of newborn birth weight, especially among early adolescents. Future research on LBW and possibly other adverse birth outcomes should consider early adolescents as a separate sub-group of higher risk.

Comparison of prenatal care coverage in early adolescents, late adolescents, and adult pregnant women in the Peruvian Amazon.

OBJECTIVE: To compare prenatal care coverage between adolescent (early and late) and adult pregnant women in Iquitos, Peru. METHODS: A random sample of 4467 birth records was collected. Multivariate analyses were performed to compare prenatal care coverage in all adolescent (10-14 years, 15-19 years) and adult (>or=20 years) age groups and then for primiparous women only. RESULTS: The mean number of visits was 5.0 for adolescents aged 10-14 years, 6.1 for adolescents aged 15-19 years, and 6.2 for women aged 20 years or older. For primiparous women, the means were 5.1, 6.2, and 6.8, for the respective age groups. Both the proportion attending and the number of prenatal visits were significantly lower in primiparous adolescents aged 10-14 years than in primiparous women aged 20 years or older (aOR 0.25; 95% CI, 0.10-0.62 and aRR 0.83; 95% CI, 0.74-0.94, respectively). CONCLUSION: All women attended prenatal care more frequently than the WHO's recommended 4 visits; however, early adolescents attended significantly less often than late adolescents or adult women. Further study of this inequality is warranted to adequately inform local health services.

Clinical spectrum of pulmonary involvement in leptospirosis in a region of endemicity, with quantification of leptospiral burden.

BACKGROUND: Pulmonary involvement in leptospirosis remains poorly recognized in regions where it is endemic, despite reports of recent outbreaks and epidemic disease. METHODS: A prospective, population-based study was carried out to identify febrile patients exposed to Leptospira in urban and rural contexts in Iquitos, Peru. Evidence of exposure to Leptospira was obtained by serologic testing, and diagnosis of leptospirosis was confirmed in pulmonary cases by culture or quantitative real-time PCR assay. RESULTS: Of 633 consecutively enrolled febrile patients, 321 (50.7%) had antileptospiral IgM antibodies or high titers of antileptospiral antibodies. Seven patients with histories of only urban exposure to leptospires had severe pulmonary manifestations; of these, 5 patients died; 4 of the deaths were caused by pulmonary hemorrhage, and 1 was caused by acute respiratory distress syndrome and multiorgan failure. Real-time, quantitative PCR assay showed high levels of leptospiremia (>or=10(4) leptospires/mL) in most fatal cases; 1 patient, from whom tissue specimens were obtained at autopsy, had >or=10(5) leptospires/g of lung, kidney, and muscle tissue. DISCUSSION. This study demonstrates the underdiagnosis of leptospirosis in a region of high endemicity and the underrecognition of grave pulmonary complications. Pulmonary involvement in leptospirosis was present in urban but not rural areas. Presumptive treatment for leptospirosis should be initiated immediately in the appropriate epidemiological and clinical context.