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BACKGROUND: Evidence on risk factors for respiratory syncytial virus (RSV) in low-resource settings is limited. In Mozambican children <2 y of age with severe acute respiratory infection (SARI), we explored risk factors for RSV, described its seasonal variation and assessed associations between RSV and a life-threatening condition. METHODS: We retrospectively included participants presenting in 2017-2018 in two hospitals in Maputo. RSV was detected and subtyped using real-time quantitative reverse transcription polymerase chain reaction on nasopharyngeal swabs. We used logistic regression and χ2 tests to assess associations and Spearman's correlation coefficient to assess the correlation between weather measurement and RSV positivity. RESULTS: RSV was detected in 23.1% (n=109) of 472 included children and in 50.0% (20/40) of those <3 months old. Being <3 months (vs >1 y) was associated with RSV (adjusted odds ratio 4.3 [95% confidence interval 2.1-8.5]). RSV status was not associated with experiencing a life-threatening condition. RSV A and B co-circulated during the study period, but one type predominated in each year. In 2017, the RSV positivity rate was correlated with monthly average temperature (r=0.793, p=0.002) and precipitation (r=0.596, p=0.041). CONCLUSIONS: In Mozambican children with SARI, RSV was prevalent, especially in neonates. However, RSV was not associated with a life-threatening condition.
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Tuberculosis (TB) is a major global health threat that claims more than one million lives annually. With a quarter of the global population harbouring latent TB, post-exposure vaccination aimed at high-risk populations that could develop active TB disease would be of great public health benefit. Mucosal vaccination is an attractive approach for a predominantly lung disease like TB because it elicits both local and systemic immunity. However, the immunological consequence of mucosal immunisation in the presence of existing lung immunity remains largely unexplored. Using a mycobacterial pre-exposure mouse model, we assessed whether pre-existing mucosal and systemic immune responses can be boosted and/or qualitatively altered by intranasal administration of spore- and nanoparticle-based subunit vaccines. Analysis of lung T cell responses revealed an increasing trend in the frequency of important CD4 and CD8 T cell subsets, and T effector memory cells with a Th1 cytokine (IFNγ and TNFα) signature among immunised mice. Additionally, significantly greater antigen specific Th1, Th17 and IL-10 responses, and antigen-induced T cell proliferation were seen from the spleens of immunised mice. Measurement of antigen-specific IgG and IgA from blood and bronchoalveolar lavage fluid also revealed enhanced systemic and local humoral immune responses among immunised animals. Lastly, peripheral blood mononuclear cells (PBMCs) obtained from the TB-endemic country of Mozambique show that individuals with LTBI showed significantly greater CD4 T cell reactivity to the vaccine candidate as compared to healthy controls. These results support further testing of Spore-FP1 and Nano-FP1 as post-exposure TB vaccines.
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Nanopartículas , Tuberculose , Animais , Camundongos , Administração Intranasal , Leucócitos Mononucleares , Pulmão , Esporos , Vacinas de Subunidades Antigênicas , ImunidadeRESUMO
Introduction: The large family of PE and PPE proteins accounts for as much as 10% of the genome of Mycobacterium tuberculosis. In this study, we explored the immunogenicity of three proteins from this family, PE18, PE31, and PPE26, in humans and mice. Methods: The investigation involved analyzing the immunoreactivity of the selected proteins using sera from TB patients, IGRA-positive household contacts, and IGRA-negative BCG vaccinated healthy donors from the TB endemic country Mozambique. Antigen-recall responses were examined in PBMC from these groups, including the evaluation of cellular responses in healthy unexposed individuals. Moreover, systemic priming and intranasal boosting with each protein, combined with the Quil-A adjuvant, were conducted in mice. Results: We found that all three proteins are immunoreactive with sera from TB patients, IGRA-positive household contacts, and IGRA-negative BCG vaccinated healthy controls. Likewise, antigen-recall responses were induced in PBMC from all groups, and the proteins stimulated proliferation of peripheral blood mononuclear cells from healthy unexposed individuals. In mice, all three antigens induced IgG antibody responses in sera and predominantly IgG, rather than IgA, responses in bronchoalveolar lavage. Additionally, CD4+ and CD8+ effector memory T cell responses were observed in the spleen, with PE18 demonstrating the ability to induce tissue-resident memory T cells in the lungs. Discussion: Having demonstrated immunogenicity in both humans and mice, the protective capacity of these antigens was evaluated by challenging immunized mice with low-dose aerosol of Mycobacterium tuberculosis H37Rv. The in vitro Mycobacterial Growth Inhibition Assay (MGIA) and assessment of viable bacteria in the lung did not demonstrate any ability of the vaccination protocol to reduce bacterial growth. We therefore concluded that these three specific PE/PPE proteins, while immunogenic in both humans and mice, were unable to confer protective immunity under these conditions.
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Mycobacterium tuberculosis , Humanos , Camundongos , Animais , Leucócitos Mononucleares , Vacina BCG , Antígenos de Bactérias , Imunoglobulina GRESUMO
Este artigo pretende contextualizar o processo de melhoria da qualidade do ensino superior em Moçambique, desde a sua concepção, abordando, de forma sequencial, os instrumentos e mecanismos criados para a sua implementação; descreve, de forma sumária, o processo de avaliação e acreditação do curso de Licenciatura em Medicina na Faculdade de Medicina da Universidade Eduardo Mondlane, referindo-se também aos desafios e benefícios relacionados a este processo.
This article aims to contextualise the process of improving the quality of higher education in Mozambique, from its inception, addressing, in a sequential manner, the instruments and mechanisms created for its implementation; it describes, in summary form, the process of evaluation and accreditation of the degree course in Medicine at the Faculty of Medicine of the Eduardo Mondlane University, also referring to the challenges and benefits related to this process.
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Humanos , Masculino , FemininoRESUMO
Background: Although blood transfusion is an intervention that saves lives, it poses significant risks to the blood receivers, including the transmission of bloodborne pathogens. We aimed at determining the prevalence of Human Immunodeficiency Virus (HIV), Hepatitis B virus (HBV), and Hepatitis C virus (HCV) in candidates approved for blood donation, and in samples considered to be negative in reference blood banks in Mozambique. Methods: A cross-sectional study was performed between November 2014 and October 2015 in Maputo and Beira cities. Demographic information was obtained from all consenting blood donors using a structured questionnaire. Plasma samples were screened for HIVAb/Ag combinations, HBsAg and Anti-HCV. Blood donors considered to be negative by serological testing were re-tested in pools of six plasma samples using nucleic acid testing (NAT). Results: Most blood donors were male 2,320 (83.4%) with an age range of 18 to 34 years. The overall seroprevalence of HIV, HBV and HCV infections among blood donors approved for donation was 4.6% (127; 95% CI 3.8-5.4), 4.5% (124; 95% CI 3.7-5.3) and 0.4% (11; 95% CI 0.2-0.7), respectively. The overall frequency by NAT of HIV RNA, HBV DNA, and HCV RNA in serologically negative blood donor samples was 2.6 per 1000 blood donors (7; 95% CI 1.1-5.4); 12.5 per 1000 blood donors (33; 95% CI 8.6-17.5) and 2.6 per 1000 blood donors (6; 95% CI 1.0-5.7), respectively. Conclusion: Our results show high seroprevalence of HIV and HBV infections in blood donors approved for donation, and high frequency of molecular biomarkers of HIV, HBV, and HCV in blood considered to be safe. These results suggest the need for a new blood screening policy in Mozambique, including the use of NAT to detect infectious blood donations during the immunologically negative window.
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Humanos , Masculino , Feminino , Adulto , Adulto Jovem , Doadores de Sangue , Infecções por HIV/epidemiologia , Hepatite C/epidemiologia , Hepatite B/epidemiologia , DNA Viral/sangue , RNA Viral/sangue , Infecções por HIV/diagnóstico , Estudos Soroepidemiológicos , Hepatite C/diagnóstico , Hepatite B/diagnóstico , Moçambique/epidemiologiaRESUMO
Mozambique has a generalized HIV epidemic, among pregnant women, HIV prevalence is estimated at 15.8% with a vertical transmission rate of 14%, more than double global targets. We evaluate electronic national health information system (SIS-MA) performance to verify if the data flow procedures met its objectives and evaluated the prevention of mother-to-child transmission (PMTCT) surveillance system to access its attributes and usefulness. we conducted a descriptive, cross-sectional evaluation of the PMTCT surveillance system in eight facilities in Gaza and Inhambane provinces using the centers for disease control and prevention guidelines (2001). For data quality, we cross-referenced patient registries from health facilities against the SIS-MA. We also interviewed 34 health technicians, using a Likert scale, to assess the following attributes of the PMTCT surveillance system: simplicity, stability, flexibility, acceptability, timeliness and data quality, usefulness of the system and knowledge of PMTCT. regarding the simplicity measure, we verified that the registry books contain more than 30 variables. The system was 83% flexible in maintaining functionality with the introduction of new health facilities in the system. The completeness of the data was 50% and concordance of data from the register book and monthly reports was 89%. the PMTCT SIS-MA is useful in supporting the collection, analysis, interpretation and continuous and systematic dissemination of health data that are used to define and monitor public health policies in Mozambique. However, continued efforts are needed to improve data quality to ensure that the SIS-MA can adequately monitor the PMTCT program and contribute to reduced vertical transmission.
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Humanos , Masculino , Feminino , Complicações Infecciosas na Gravidez/virologia , Infecções por HIV/prevenção & controle , Síndrome de Imunodeficiência Adquirida Felina/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Moçambique , Gravidez , Infecções por HIV/transmissão , Vigilância da População , Inquéritos e Questionários , Síndrome de Imunodeficiência Adquirida Felina/transmissãoRESUMO
As doenças infecciosas ocorrem de forma desproporcional entre homens e mulheres. Muitas vezes, a severidade e o resultado da doença estão geralmente relacionados ao sexo. Os factores inerentes a estas diferenças ainda estão a ser estudados. Contudo, alguns estudos apontam o sexo como um dos factores principais das difer- enças da resposta imunológica às infecções. As mulheres desenvolvem naturalmente uma imunidade inata, celular e humoral com algumas utuações devido aos níveis hormonais que naturalmente variam durante os ciclos menstruais, gravidez, menopausa ou pelo uso de anticonceptivos hormonais ou o uso de tratamentos hormonais. Entretanto, as hormonas masculinas também têm sido implicadas na imunoregulação. A testesterona por exemplo causa o declínio de certas respostas imunológicas e os indivíduos jovens do sexo masculino são muitas vezes susceptíveis a infecções severas comparados às mulheres ou a homens adultos. Por outro lado, o género joga um papel importante na susceptibilidade às infecções transmitidas por vectores. Outros estudos apontam que o padrão hormonal no seio da família e a química da pele in uenciam na susceptibilidade à picada por mosquitos e outros vectores nos homens e mulheres. As diferenças comportamentais, ocupacionais e culturais também estão relacionadas com a exposição a vectores, assim como o uso de medidas de protecção individual e a procura pelos cuidados de saúde. Tomando em conta estes aspectos, é importante que futuros estudos imunológicos, epidemiológi- cos, comportamentais, de conhecimentos atitudes e práticas tenham em conta o sexo como uma variável, para uma melhor interpretação dos resultados e melhores práticas de saúde, princi- palmente no que tange ao tratamento das doenças infecciosas.
Infectious diseases occur di erently in men and women. Usually the severity and the result of the disease are related to the gender. Although some studies indicate the gender as one of main factor of immunological di erences, the causes of these di erences are still to be revealed. However, Women naturally develop innate immune response, cellular and humoral response with some uctuations due to the level of hormones that varies during the menstrual cycle, pregnancy and menopause, or due to the use of anti-conception pill or the use of hormonal treatments. e hormones from males also are implicated in immunoregulation. Testosterone decreases certain immune responses and young males are more susceptible to severe infections compared to adult males and females. In other hand, the gender was shown to play an important role on the susceptibility to vector transmitted diseases where the hormonal pattern within the family and the chemistry of the skin in uence the susceptibility to mosquito's bite and other vectors in men and women. e behavior, occupational and cultural behaviors in uence the exposure to vectors, but also the use of individual protection measures and the search for health services. Taking together, it's very important that future studies address gender and sex di erences in their designs, in order to conduct better conclusions and heath practices related to infectious diseases treatment or prevention.
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Humanos , Masculino , Feminino , Doenças Transmissíveis , Caracteres Sexuais , Identidade de Gênero , Sexo , Menopausa , Suscetibilidade a Doenças , Hormônios , Imunidade , MoçambiqueRESUMO
A diarreia causada por Cryptosporidium spp. é comum em crianças e culmina com elevadas taxas de morbi-mortalidade, sobretudo nos países em desenvolvimento. A técnica convencional para o diagnóstico de Cryptosporidium spp. é a microscopia óptica, contudo, o Ensaio de Imunoabsorção Enzimática (ELISA) também tem sido usado. O objectivo deste estudo foi de comparar a performance do ELISA (ensaio comercial) em relação a microscopia óptica na detecção de Cryptosporidium spp. em fezes diarreicas de crianças admitidas no Hospital Geral de Mavalane (HGM) de Maio de 2014 a Fevereiro de 2015. No total, 130 amostras de fezes foram testadas, primeiramente por microscopia óptica e depois por ELISA. A estatística descritiva, sensibilidade, especi cidade e valores preditivos negativo e positivo foram usados para analisar os dados.A microscopia permitiu a identi cação de Cryptosporidium spp., Entamoeba hystolitica/díspar/moshovskii, Giardia intestinalis, Ascaris lumbricóides, Trichuris trichiura e Balantidium coli. Doze (9.2%) amostras foram positivas para Cryptosporidium spp., contra 22 (16.9%) identi cadas por ELISA. Esta diferença foi estatisticamente signi cativa (p = 0.002). A frequência de detecção deste patógeno por microscopia foi maior em crianças dos 12 aos 23 meses (4.6%), enquanto por ELISA foi maior em crianças dos zero aos 11 meses. A sensibilidade do ELISA na detecção de antígenos de Cryptosporidium spp. foi de 58.3%, enquanto a especi-cidade foi de 81.4%. Os resultados encontrados ressaltam a necessidade de uma ferramenta de diagnóstico complementar tal como o ELISA, para con rmar o diagnóstico em pacientes com sinais clínicos típicos de criptosporidiose mas com resultado negativo por microscopia.
Diarrhea caused by Cryptosporidium spp. is common in children and ends with high morbidity and mortality rates, mostly in developing countries. e conventional technique for the diagnosis of Cryptosporidium spp. is the optical microscopy, however, the Enzyme-linked immunosorbent assay (ELISA) is also being implemented. e aim of this study was to compare the performance of ELISA (commercial immunoassay) in relation to optical microscopy to detect Cryptosporidium spp. in diarrheic feces of children admitted to Mavalane General Hospital from May 2014 to February 2015. Overall 130 stool samples were tested rstly by optical microscopy and then by ELISA. Descriptive statistics, sensitivity, speci city, negative and positive predictive value were used to analyze the data. e microscopy detected 12 (9.2%) Cryptosporidiumspp., positive samples and ELISA identi ed 22 (16.9%). is di erence was statistically signi cant (p = 0.002). e frequency of detection by microscopy was higher in children from 12 to 23 months (4.6%), while by ELISA was higher in those from zero to 11 months. e microscopy enabled the identi cation of other parasites such as Entamoeba hystolitica/díspar/moshovskii, Giardia intestinalis, Ascaris lumbricóides, Trichuris trichiura and Balantidium coli. e sensitivity of the ELISA in detection of Cryptosporidium spp. antigens was 58.3%, while the speci city was 81.4%. Taking all together, our results highlight the need of a complementary diagnostic tool, such as this ELISA, to con rm the diagnosis in patients with typical clinicalsymptoms of cryptosporidiosis but negative results by microscopy.
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Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Criptosporidiose/complicações , Criptosporidiose/parasitologia , Diarreia Infantil/parasitologia , Microscopia/instrumentação , Ensaio de Imunoadsorção Enzimática/instrumentação , Ensaio de Imunoadsorção Enzimática/mortalidadeRESUMO
Background: The optimum age for measles vaccination varies from country to country and thus a standardized vaccination schedule is controversial. While the increase in measles vaccination coverage has produced significant changes in the epidemiology of infection, vaccination schedules have not been adjusted. Instead, measures to cut wild-type virus transmission through mass vaccination campaigns have been instituted. This study estimates the presence of measles antibodies among six- and nine-month-old children and assesses the current vaccination seroconversion by using a non invasive method in Maputo City, Mozambique. Methods: Six- and nine-month old children and their mothers were screened in a cross-sectional study for measles-specific antibodies in oral fluid. All vaccinated children were invited for a follow up visit 15 days after immunization to assess seroconversion. Results: 82.4% of the children lost maternal antibodies by six months. Most children were antibody-positive post-vaccination at nine months, although 30.5 % of nine month old children had antibodies in oral fluid before vaccination. We suggest that these pre-vaccination antibodies are due to contact with wild-type of measles virus. The observed seroconversion rate after vaccination was 84.2%. Conclusion: These data indicate a need to re-evaluate the effectiveness of the measles immunization policy in the current epidemiological scenario.