Etiology of Diarrhea in Children Younger Than 5 Years Attending the Bengo General Hospital in Angola.

BACKGROUND: Diarrheal disease is among the leading causes of death in children younger than 5 years, especially in developing countries. The aim of this study was to investigate the most frequent etiological agents of diarrhea and its associated factors in children younger than 5 years attending the Bengo General Hospital in Angola. METHODS: From September 2012 through December 2013, stool samples were collected from 344 children presenting with diarrhea to investigate the presence of viral, bacterial and parasitic agents. Relevant sociodemographic and clinical data were obtained from parents and caregivers. RESULTS: An enteric pathogen was detected in 66.6% of stool samples: Cryptosporidium spp. (30.0%), rotavirus (25.1%), Giardia lamblia (21.6%), diarrheagenic Escherichia coli (6.3%), Ascaris lumbricoides (4.1%), adenovirus (3.8%), Strongyloides stercoralis (3.5%), astrovirus (2.6%), Hymenolepis nana (1.7%), Entamoeba histolytica/dispar (0.9%), Taenia spp. (0.6%), Trichuris trichiura (0.3%) and Entamoeba histolytica (0.3%). Children younger than 12 months were more frequently infected with Cryptosporidium spp. compared with older children (age: 12-59 months), independently of sex, season, lethargy and wasting [odds ratio (OR): 3.5, 95% confidence interval (95% CI): 2.0-6.2]. Age (OR: 5.0, 95% CI: 2.6-9.3), vomiting (OR: 2.7, 95% CI: 1.5-4.8) and type of admission (inpatients, OR: 0.5, 95% CI: 0.3-0.9) were significantly associated with rotavirus infection. CONCLUSIONS: This study demonstrates high rates of infection with an enteric pathogen, particularly in children younger than 12 months, emphasizing the need to address diarrheal disease in this age group.

Infection by Intestinal Parasites, Stunting and Anemia in School-Aged Children from Southern Angola.

INTRODUCTION: Intestinal parasites are responsible for morbidity in children worldwide, especially in low income countries. In the present study we determine the prevalence of intestinal parasites and explore its association with anemia and stunting in school-aged children. METHODS: A cross-sectional study was conducted from September to October 2010 enrolling 328 children attending the primary school in Lubango, the second largest city after the capital Luanda. Stool samples were collected for parasite detection through microscopy and molecular identification of Entamoeba histolytica and Entamoeba dispar. Stunting was assessed using the z-scores of height for age and hemoglobin concentration was determined using a portable hemoglobin analyzing system. RESULTS: The global prevalence of pathogenic intestinal parasites was 44.2%, the most common being Ascaris lumbricoides (22.0%), Giardia lamblia (20.1%) and Hymenolepis nana (8.8%). Molecular detection revealed that 13.1% of the children carried E. dispar and 0.3% were infected with E. histolytica. The prevalence of stunting (mild to severe) was 41.5%. Stunting was more frequent in older children (p = 0.006, OR = 1.886), while anemia was more frequent in younger children (p = 0.005, OR = 2.210). The prevalence of anemia was 21.6%, and we found a significant association with infection by H. nana (p = 0.031, OR = 2.449). CONCLUSIONS: This is one of the few published studies reporting intestinal parasites infection, nutritional status and anemia in children from Angola. Furthermore, the present work highlights the importance of regular intestinal parasites screening in children.

Giardia duodenalis and soil-transmitted helminths infections in children in São Tomé and Príncipe: do we think Giardia when addressing parasite control?

Giardia duodenalis prevalence is commonly as high as soil-transmitted helminths (STH), nevertheless is not considered for large-scale chemotherapy through mass drug administration (MDA) due to its short incubation period and frequent reinfections, its control being associated to improving access to water and sanitation. A study enrolling 444 children attending preschools was conducted in May 2011 during a deworming campaign. Faecal samples were obtained and analysed through microscopy of wet mounting and after Kato-Katz and formol-ether concentration techniques. The majority of children were infected with at least one pathogenic parasite (86.7%, 385 of 444). Ascaris lumbricoides and Trichuris trichiura (56.3%, 250 of 444 and 52.5%, 233 of 444, respectively) were the most frequent parasites followed by G. duodenalis infecting 41.7% (185 of 444) of the children. The present work aimed at obtaining updated information concerning intestinal parasite infections in children attending preschools in São Tomé and Príncipe and to contribute for the adequate management of the enteric infections.

Angola's 2013 dengue outbreak: clinical, laboratory and molecular analyses of cases from four Portuguese institutions.

INTRODUCTION: Dengue virus (DENV) is the arbovirus with the widest impact on human health. In Africa in general, and in Angola in particular, the epidemiology and public health impact of DENV is far from clear. However, rapid population growth, unplanned urbanization, increased international travel, and the presence of virus major vector (Aedes aegypti) in the country suggest that DENV transmission may occur. METHODOLOGY: In parallel to the occurrence of a dengue outbreak affecting the capital of Angola, between March and July 2013 four Portuguese institutions diagnosed dengue infection in 146 individuals returning to Portugal. Clinical presentation, laboratory findings, and molecular analyses of partial viral genomic segments were performed. RESULTS: The mean age of the individuals included in this study was 42 years old, the majority being men of Portuguese nationality, reporting various lengths of stay in Angola. Fever was the most reported clinical sign, being frequently associated (61.0%) with myalgia and headache. Hematological values, including hematocrit, white-blood cell and platelets counts, correlated with the absence of severe or complicated cases, or coagulation disorders. No deaths were observed. Viral NS1 was detected in 56.2% of the samples, and all NS1 negative cases had anti-dengue IgM antibodies. RT-PCR indicated the presence of DENV1, which was confirmed by phylogenetic analysis of 25 partial NS5 viral sequences. CONCLUSION: The DENV cases analyzed conformed to classical and uncomplicated dengue, caused by the suggested exclusive circulation of a genetically homogeneous DENV1 of genotype III, apparently with a single origin.

Intestinal parasites in children hospitalized at the Central Hospital in Maputo, Mozambique.

INTRODUCTION: Intestinal parasites are important contributors to the global disease burden, especially in children of low-income countries. The present study determined the frequency of intestinal parasites in children hospitalized at the diarrhea section of the Infectious-Contagious Diseases ward and at the Malnutrition ward of the Department of Pediatrics of the Maputo Central Hospital in Mozambique. METHODOLOGY: This pilot study conducted between February and March 2009 enrolled a total of 93 children between 1.5 and 48.2 months of age; 87.1% were younger than 24 months. Parasite detection in stool samples was achieved using direct microscopic observation and Ritchie's concentration technique. RESULTS: Infection with pathogenic intestinal parasites was detected in 16.1% (15/93) of the children. Giardia duodenalis and Trichuris trichiura were the most common parasites (6.5%, 6/93 each), followed by Ascaris lumbricoides (2.2%, 2/93). One case of mixed infection with A. lumbricoides plus T. trichiura was also detected. CONCLUSION: This study reinforces the importance of routinely examining stool samples for the diagnosis of intestinal parasites (including protozoa) in children hospitalized in endemic areas.

Molecular and Clinical Characterization of Giardia duodenalis Infection in Preschool Children from Lisbon, Portugal.

Giardia duodenalis is the most prevalent intestinal protozoan infection especially in children. In Portugal scarce data are available relative to this infection in preschoolers. The present study was conducted from April to July 2009 in public preschools in Lisbon enrolling 316 children. Stool examination was performed through microscopy. Molecular analysis was conducted in all positive samples for G. duodenalis in order to determine the assemblage and subassemblage of this parasite. Eight of the preschoolers studied children (2.5%, 8/316) were infected with G. duodenalis. Additionally the brother of one of the infected children was also infected. Genotyping analysis targeting ssu-rRNA and ß -giardin loci revealed six infections with assemblage A and 3 with assemblage B. Sub-assemblage determination was possible in four of the samples, with three A2 and one A3. The limited number of cases precluded an association of a determined symptom with an assemblage. The data presented here show the relevance of considering G. duodenalis analysis in children with intestinal complaints even in developed countries.

[Giardia duodenalis and chronic malnutrition in children under five from a rural area of Guinea-Bissau]. / Giardia Duodenalis e Desnutrição Crónica em Crianças Menores de Cinco Anos de uma Região Rural da Guiné-Bissau.

INTRODUCTION: Malnutrition and infections by intestinal parasites such as Giardia duodenalis coexist in the same geographical regions, reaching the highest prevalence in developing countries. The cycle of malnutrition and infection implies that both conditions can aggravate each other and compromise the growth and development of children with special relevance for under-five. The aim of this study was to investigate the association between chronic malnutrition and infection by G. duodenalis in children under five in a rural community in Guinea-Bissau. MATERIAL AND METHODS: A case-control study that included 109 children aged 0 to 59 months of a rural community in Guinea-Bissau was conducted. The anthropometric assessment of children in the study identified 31 cases of chronic malnutrition (z-score height for age < -2) and 78 controls (z-score height for age = -2). Microscopic examination of stools was performed for detection and identification of G. duodenalis and other parasites. RESULTS: The microscopic analysis of stool samples revealed G. duodenalis infection in 29.0% (9/31) of cases and 35.9% (28/78) of controls. No association between the infection with G. duodenalis and chronic malnutrition in children under study could be established. DISCUSSION AND CONCLUSION: The results reinforce the interest in designing further studies exploring this association in different regions and epidemiological settings, while direct to the importance of the criteria for malnutrition definition which influences the subsequent analysis.

Introdução: A desnutrição e as infecções por parasitas intestinais como Giardia duodenalis coexistem nas mesmas regiões geográficas, atingindo maiores prevalências em países em desenvolvimento. O ciclo da desnutrição e infecção implica que ambas as condições se podem agravar mutuamente e comprometer o crescimento e desenvolvimento das crianças, com especial relevância para as menores de cinco anos. O objectivo do presente estudo foi investigar a associação entre a desnutrição crónica e a infecção por G. duodenalis em crianças de uma comunidade rural da Guiné-Bissau.Material e Métodos: Realizou-se um estudo de caso-controlo que incluiu 109 crianças com idades entre os 0 e os 59 meses de uma comunidade rural da Guiné-Bissau. A avaliação antropométrica das crianças em estudo permitiu identificar 31 casos de desnutrição crónica (z-score estatura para a idade < -2) e 78 controlos (z-score estatura para a idade ≥ -2). Foi realizado exame microscópico de fezes para a detecção e identificação de G. duodenalis e de outros parasitas.Resultados: Foi detectada infecção por G. duodenalis em 29,0% (9/31) dos casos e 35,9% (28/78) dos controlos. Não foi encontrada associação entre a infecção por G. duodenalis e a desnutrição crónica nas crianças em estudo.Discussão e Conclusão: Os resultados obtidos mantêm em aberto o interesse em desenhar estudos que explorem esta associação em diferentes regiões e contextos epidemiológicos, apontando para a reflexão sobre a importância dos critérios de definição de desnutrição e concomitantemente da análise subsequente.

Molecular identification of T. brucei s.l. in tsetse flies after long-term permanence in field traps.

BACKGROUND: Tsetse flies (Glossina spp.) are responsible for the transmission of trypanosomes, agents of animal and Human African Trypanosomiasis (HAT). These diseases are associated with considerable animal and human economical loss, morbidity and mortality. The correct identification of trypanosomes species infecting tsetse flies is crucial for adequate control measures. Identification presently requires technically difficult, cumbersome and expensive on-site fly dissection. To obviate this difficulty we explored the possibility of correctly identifying trypanosomes in tsetse collected, under field conditions, only for number determination. METHODOLOGY: Tsetse flies, that remained exposed for weeks in field traps in the Vista Alegre HAT focus in Angola, were obtained. The flies were not dissected on site and were stored at room temperature for months. DNA extraction using the whole tsetse bodies and PCR analysis were performed in 73 randomly chosen flies. RESULTS: Despite the extensive degradation of the tsetse, DNA extraction was conducted successfully in 62 out of the 73 flies. PCR analysis detected the presence of T. brucei s.l DNA in 3.2 % of the tsetse. CONCLUSIONS: This approach could be cost-effective and suitable for vector related HAT control activities in the context of countries where entomological trained personnel is missing and financial resources are limited.

An alternative approach to detect Trypanosoma in Glossina (Diptera, Glossinidae) without dissection.

BACKGROUND: Determining if a tsetse fly is infected by trypanosomes and thus potentially able to transmit trypanosome-related human and animal diseases is an extremely laborious and time-consuming task to perform, especially under field conditions. In this study we tested a possible alternative approach that uses the entire insect vector for DNA extraction and PCR analysis to detect and identify Trypanosoma spp. in field collected tsetse flies. METHODOLOGY: DNA extraction was performed using a method originally developed for tick DNA extraction followed by PCR detection and identification of Trypanosoma spp. RESULTS: Two out of 62 flies captured in Equatorial Guinea carried DNA of T. brucei s.l. and Trypanosoma vivax. T. congolense forest, T. congolense savannah and T. congolense Kilifi were not detected. CONCLUSIONS: The approach we employed allowed the molecular detection and species identification of trypanosomes using the whole vector body for DNA extraction. Although the approach does not give direct information on tsetse infectivity, it provides valuable information about trypanosome species circulating in a tsetse fly vector population. The method allows an effective processing of a large number of field captured tsetse in a central laboratory.

The control of an epidemic outbreak of Marburg hemorrhagic fever in Angola, 2004-2005 / No disponible

Entre Octubre del 2004 y Septiembre del 2005 Angola vivió un brote epidémico de fiebre hemorrágica debida al virus Marburg. La epidemia se dio por oficialmente por concluida el 7 de Noviembre del 2005, y se consideró la más grave de las ocurridas en todo el mundo, con 252 casos y 227 muertes, lo que suponía una tasa de mortalidad del 90%. Considerando que es un agente patógeno de gran virulencia para el cual no hay vacunas o tratamiento específico, estas epidemias precisan de una enorme cantidad de recursos humanos, financieros y técnicos tanto nacionales como internacionales Es importante poner de manifiesto que el laboratorio del Center for Diseases Control de Atlanta fue el responsable del primer aislamiento del virus y de su identificación como causante de la epidemia. Posteriormente fue el encargado de monitorizar la epidemia y estudiar todas las muestras biológicas recogidas de los casos sospechosos. Hasta este momento ha sido imposible identificar el foco primario de la enfermedad, aunque existen sugerencias a nivel local sobre la posibilidad de que el hospital provincial de UIge haya sido el sitio inicial y responsable de la diseminación de la epidemia a través de la infección nosocomial. En una segunda fase la ausencia de una adecuada educación para la salud, el pánico y las tradiciones culturales locales fueron los elementos cruciales para la diseminación de la enfermedad a otras provincias del país. En este contexto, la participación de sociólogos y antropólogos fue un factor clave para el control de las epidemias, en paralelo a las medidas de bioseguridad y detección activa emprendidas (AU)

Angola has lived an epidemic outbreak of hemorrhagic fever caused by Marburg virus between October 2004 and September 2005. The epidemic was officially terminated in November 7th 2005, and considered the most severe ever occurred in the world, with 252 cases and 227 deaths, with a lethality rate of 90%. Considering that it is a pathogenic agent of great virulence for which there are no vaccines or specific treatment, these epidemics caused a huge recruitment of national and international human, financial and technical resources despite some local constraints. It must be outlined that CDC-Atlanta laboratory was the responsible for the first isolation of the virus as the cause of the epidemics, and later on, for monitoring the epidemics and manipulating all biological samples collected from suspected patients. Until now it was impossible to identify the primary focus of the disease, though there are suggestions from local oral comments that Uige provincial hospital may have been the initial site and responsible for the dissemination of the epidemics through nosocomial infection. In a second phase, lack of proper health education, panic and local cultural traditions were the crucial elements for disease spread to other provinces of the country. In this context, the participation of sociologist and anthropologists was a key factor for the epidemics control, in parallel with the biosafety and active survey measures undertaken (AU)

Studies in a co-infection murine model of Plasmodium chabaudi chabaudi and Leishmania infantum: interferon-gamma and interleukin-4 mRNA expression

This work aimed to study the T helper type 1/2 (Th1/Th2) cytokine profile in a co-infection murine model of Plasmodium chabaudi chabaudi and Leishmania infantum. Expression of interferon-gamma and interleukin-4 (IL-4) was analyzed, in spleen and liver of C57BL/6 mice, by reverse transcriptase-polymerase chain reaction. High levels of IFN-gamma expression did not prevent the progression of Leishmania in co-infected mice and Leishmania infection did not interfere with the Th1/Th2 switch necessary for Plasmodium control. The presence of IL-4 at day 28 in co-infected mice, essential for Plasmodium elimination, was probably a key factor on the exacerbation of the Leishmania infection.

Studies in a co-infection murine model of Plasmodium chabaudi chabaudi and Leishmania infantum: interferon-gamma and interleukin-4 mRNA expression.

This work aimed to study the T helper type 1/2 (Th1/Th2) cytokine profile in a co-infection murine model of Plasmodium chabaudi chabaudi and Leishmania infantum. Expression of interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) was analyzed, in spleen and liver of C57BL/6 mice, by reverse transcriptase-polymerase chain reaction. High levels of IFN-gamma expression did not prevent the progression of Leishmania in co-infected mice and Leishmania infection did not interfere with the Th1/Th2 switch necessary for Plasmodium control. The presence of IL-4 at day 28 in co-infected mice, essential for Plasmodium elimination, was probably a key factor on the exacerbation of the Leishmania infection.

Molecular and phylogenetic characterization of Theileria spp. parasites in autochthonous bovines (Mirandesa breed) in Portugal.

A survey was conducted during the months of April-June 2003 in the northeast Portugal (Bragança district) in order to characterize the hemoparasite population of an autochthonous Mirandesa breed of Bos taurus. The polymerase chain reaction (PCR) analysis of the bovine blood revealed that 3 out of 116 animals were infected with Theileria and/or Babesia parasites, while reverse line blot hybridisation (RLB) analysis showed that these animals were infected with Theileria buffeli/orientalis. Cloning and sequencing confirmed the RLB results. Database sequence searches combined with phylogenetic analysis of the partial 18S ribosomal RNA gene sequences obtained enabled us to place the parasites in question as members of the T. buffeli/orientalis group, confirming the PCR/RLB diagnosis.

Kinetics of cytokine expression in mice with invasive aspergillosis: lethal infection and protection.

Aspergillus fumigatus causes lethal invasive aspergillosis in cortisone-treated mice while immunized mice are protected. Kinetics of interferon (IFN)-gamma, tumor necrosis factor-alpha, interleukin (IL)-12p40, IL-4 and IL-10 expression were assessed by reverse transcription-PCR in the spleen and lungs of mice. After immunization, mice were protected from otherwise lethal infection, with concomitant high expression levels of IFN-gamma early in the lungs and later in the spleen. In the lethal infection model cortisone-treated infected mice presented high expression levels of IL-10 in the spleen and in the lungs. Immunocompetent mice were able to control the disease and presented earlier expression of IL-12p40 and IFN-gamma in lungs and spleen. These results confirm the importance of Th1 dependent immunity against invasive aspergillosis.