Risk factors and circulation pattern of respiratory syncytial virus in children under 2 years in Maputo, Mozambique.

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.

Immunogenicity of PE18, PE31, and PPE26 proteins from Mycobacterium tuberculosis in humans and mice.

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.

Mucosal and systemic immune responses after a single intranasal dose of nanoparticle and spore-based subunit vaccines in mice with pre-existing lung mycobacterial immunity.

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.

Serological analysis reveals differential antibody responses between TB patients and latently infected individuals from the TB endemic country of Mozambique.

Serological antibody profiling of tuberculosis (TB) patients and household contacts with latent TB infection (LTBI) could identify risk indicators of disease progression, and potentially also serve as an easily accessible diagnostic tool to discriminate between these two stages of Mycobacterium tuberculosis (Mtb) infection. Yet, despite significant efforts over many decades, neither application has yet fully materialised, and this is at least in part due to inconsistent and varying antibody profiles from different TB endemic regions. In this study, we conducted a retrospective exploratory analysis of serum antibodies in a cohort of active TB patients (ATB) and their interferon-gamma release assay (IGRA) positive household contacts (LTBI), as well as healthy controls (HC) from Mozambique, a country with a high TB burden from the Sub-Saharan region. Using several Mtb antigens as well as crude preparations of culture filtrate proteins (CFP) from Mtb and Bacille Calmette Guérin (BCG), we report that the most discriminatory response for TB and LTBI was observed for serum IgA antibodies to the MPT64 antigen, followed by IgG antibodies to Ag85B and CFP, with ATB patients having significantly higher levels than LTBI or BCG-vaccinated healthy controls. Conversely, sera from LTBI individuals had higher levels of IgG antibodies to the HBHA antigen than ATB. While our sample size (n = 21 for ATB, 18 for LTBI and 17 for HC) was too small to fully evaluate the diagnostic potential of these differing serological profiles, our study however preliminarily indicated high level of sensitivity (95%) and specificity (97%) of an ELISA MPT64-IgA test for discriminating TB from LTBI and healthy controls, supporting the notion that it alone, or possibly in combination with other antigens such as Ag85B or CFP could lead to development of an easily accessible diagnostic tool for TB.

Nucleic acid testing identifies high prevalence of blood borne viruses among approved blood donors in Mozambique.

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.

Evaluation of prevention of mother-to-child transmission national health information system for HIV/AIDS, in southern region of Mozambique, April to November 2016.

INTRODUCTION: 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. METHODS: 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. RESULTS: 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%. CONCLUSION: 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.

Identification of the Human Papillomavirus Genotypes, According to the Human Immunodeficiency Virus Status in a Cohort of Women from Maputo, Mozambique.

BACKGROUND: Human papillomavirus (HPV) infection is now a well-established cause of cervical cancer and other anogenital cancers. An association between human immunodeficiency virus (HIV) infection and higher HPV incidence and prevalence are commonly reported. This study was conducted to demonstrate HPV prevalence, genotypes and its characteristics, according to the HIV status in women from Maputo in Mozambique. METHODS: A total of 233 participants with ages ranging from fourteen to forty-five were included. Cervical samples were collected, DNA extracted, and HPV genotyping was performed using the HPV Direct Flow CHIP Kit. RESULTS: In total, 177 HIV-negative and 56 HIV-positive women were included in the analysis. The overall HPV prevalence was 63% and was significantly higher among HIV-positive women (79% versus 58% among HIV-negative women; p = 0.005). The prevalence of multiple HPV type infections was 32%. High-risk HPV types 52, 68, 35, 18 and 16 were the most frequent. A higher proportion of HIV-positive women had multiple HPV types compared with HIV-negative women. CONCLUSIONS: This study demonstrated a high prevalence of HPV in the study cohort. HIV-positive women were identified as having the highest HPV prevalence and infection with multiple HPV types across all ages. High-risk genotypes were the most commonly found.

Mucosal Therapy of Multi-Drug Resistant Tuberculosis With IgA and Interferon-γ.

New evidence has been emerging that antibodies can be protective in various experimental models of tuberculosis. Here, we report on protection against multidrug-resistant Mycobacterium tuberculosis (MDR-TB) infection using a combination of the human monoclonal IgA 2E9 antibody against the alpha-crystallin (Acr, HspX) antigen and mouse interferon-gamma in mice transgenic for the human IgA receptor, CD89. The effect of the combined mucosal IgA and IFN-γ; treatment was strongest (50-fold reduction) when therapy was applied at the time of infection, but a statistically significant reduction of lung bacterial load was observed even when the therapy was initiated once the infection had already been established. The protection involving enhanced phagocytosis and then neutrophil mediated killing of infected cells was IgA isotype mediated, because treatment with an IgG version of 2E9 antibody was not effective in human IgG receptor CD64 transgenic mice. The Acr antigen specificity of IgA antibodies for protection in humans has been indicated by their elevated serum levels in latent tuberculosis unlike the lack of IgA antibodies against the virulence-associated MPT64 antigen. Our results represent the first evidence for potential translation of mucosal immunotherapy for the management of MDR-TB.

An RNA-seq Based Machine Learning Approach Identifies Latent Tuberculosis Patients With an Active Tuberculosis Profile.

A better understanding of the response against Tuberculosis (TB) infection is required to accurately identify the individuals with an active or a latent TB infection (LTBI) and also those LTBI patients at higher risk of developing active TB. In this work, we have used the information obtained from studying the gene expression profile of active TB patients and their infected -LTBI- or uninfected -NoTBI- contacts, recruited in Spain and Mozambique, to build a class-prediction model that identifies individuals with a TB infection profile. Following this approach, we have identified several genes and metabolic pathways that provide important information of the immune mechanisms triggered against TB infection. As a novelty of our work, a combination of this class-prediction model and the direct measurement of different immunological parameters, was used to identify a subset of LTBI contacts (called TB-like) whose transcriptional and immunological profiles are suggestive of infection with a higher probability of developing active TB. Validation of this novel approach to identifying LTBI individuals with the highest risk of active TB disease merits further longitudinal studies on larger cohorts in TB endemic areas.

Serum proteomics of active tuberculosis patients and contacts reveals unique processes activated during Mycobacterium tuberculosis infection.

Tuberculosis (TB) is the most lethal infection among infectious diseases. The specific aim of this study was to establish panels of serum protein biomarkers representative of active TB patients and their household contacts who were either infected (LTBI) or uninfected (EMI-TB Discovery Cohort, Pontevedra Region, Spain). A TMT (Tamdem mass tags) 10plex-based quantitative proteomics study was performed in quintuplicate containing a total of 15 individual serum samples per group. Peptides were analyzed in an LC-Orbitrap Elite platform, and raw data were processed using Proteome Discoverer 2.1. A total of 418 proteins were quantified. The specific protein signature of active TB patients was characterized by an accumulation of proteins related to complement activation, inflammation and modulation of immune response and also by a decrease of a small subset of proteins, including apolipoprotein A and serotransferrin, indicating the importance of lipid transport and iron assimilation in the progression of the disease. This signature was verified by the targeted measurement of selected candidates in a second cohort (EMI-TB Verification Cohort, Maputo Region, Mozambique) by ELISA and nephelometry techniques. These findings will aid our understanding of the complex metabolic processes associated with TB progression from LTBI to active disease.

Diferenças de género e sexo na susceptibilidade às doenças infecciosas / Gender and sex difference susceptibility to infectious diseases

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.

Microscopia e Ensaio de Imunoabsorção Enzimática: detecção de Cryptosporidium spp. em fezes de crianças moçambicanas / Microscopy and Enzyme-Linked Immunosorbent Assay for Cryptosporidium spp. detection in diarrheic feces of Mozambican children

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.

Antigenic and genetic characterization of influenza viruses isolated in Mozambique during the 2015 season.

BACKGROUND: Due to the high rate of antigenic variation of influenza virus, seasonal characterization of the virus is crucial to assess and monitor the emergence of new pathogenic variants and hence formulate effective control measures. However, no study has yet been conducted in Mozambique to assess genetic, antigenic and antiviral susceptibility profile of influenza virus. METHODS: A subset of samples (n = 20) from influenza positive children detected in two hospitals in Maputo city during 2015 season as part of the implementation of influenza surveillance system, were selected. The following assays were performed on these samples: antigenic characterization by hemagglutination inhibition assay, genetic characterization by Sanger sequencing of hemagglutinin (HA) and neuraminidase (NA) and susceptibility to oseltamivir and zanamivir (NA inhibitors) by enzymatic assay. RESULTS: The A(H1N1)pdm09 subtype viruses remained closely related antigenically and genetically to the 2016 vaccine virus A/California/7/2009 and other widely distributed viruses belonging to genetic group 6B. The majority of influenza A(H3N2) viruses studied were antigenically similar to the 2016-2017 vaccine virus, A/Hong Kong/4801/2014, and their HA and NA gene sequences fell into genetic subclade 3C.2a being closely related to viruses circulating in southern Africa. The influenza B viruses were antigenically similar to the 2016 season vaccine virus and HA sequences of all three fell into the B/Yamagata-lineage, clade 3, but contained NA genes of the B/Victoria-lineage. All tested viruses were sensitive to oseltamivir and zanamivir. CONCLUSION: Overall, all Mozambican influenza A and B viruses were most closely related to Southern African viruses and all were sensitive to oseltamivir and zanamivir. These findings suggest the existence of an ecological niche of influenza viruses within the region and hence highlighting the need for joint epidemiologic and virologic surveillance to monitor the evolution of influenza viruses.

Clinical and epidemiological characterization of influenza virus infections in children with severe acute respiratory infection in Maputo, Mozambique: Results from the implementation of sentinel surveillance, 2014 - 2016.

In Sub-Saharan Africa, where burden, impact, and incidence of acute respiratory infections (ARI) are the highest in the world, conversely, the epidemiology of influenza-associated severe acute respiratory infections (SARI) is incompletely known. The aim of this study was to describe the clinical and epidemiological features of influenza-associated SARI in hospitalized children in Maputo city, Mozambique. Nasopharyngeal and oropharyngeal swabs were collected from children aged 0-14 years old who met the case definition for SARI in two hospitals in Maputo city after their parents or legal representative consented to participate. A structured questionnaire was used to collect clinical and demographic data. Typing and subtyping of influenza were performed by real-time PCR. From January 2014 to December 2016, a total of 2,007 eligible children were recruited, of whom 1,997 (99.5%) were screened for influenza by real-time PCR. The median age of participants was 16.9 months (IQR: 7.0-38.9 months) and 53.9% (1076/1991) were male. A total of 77 were positive for influenza, yielding a frequency of 3.9% (77/1,991), with the highest frequency being reported in the age group 1-5 years old. Cases of influenza peaked twice each year, during which, its frequency reached up to 60%-80%. Among all influenza confirmed cases, 33.7% (26/77), 35.1% (27/77) and 28.6% (22/77) were typed as influenza A/H3N2, A/H1N1pdm09, and B, respectively. This represents the first report of influenza in urban/sub urban setting in Mozambique and the first evidence of distribution of strains of influenza in the country. Our data showed that frequency of influenza was lower than reported in a rural setting in Mozambique and the frequency of seasonal (A/H1N1pdm09) and (A/H3N2) subtypes were similar in children with SARI.

Respiratory syncytial and influenza viruses in children under 2 years old with severe acute respiratory infection (SARI) in Maputo, 2015.

INTRODUCTION: Although respiratory syncytial virus (RSV) and influenza virus (influenza) infections are one of the leading causes of Severe Acute Respiratory Infections (SARI) and death in young children worldwide, little is known about the burden of these pathogens in Mozambique. MATERIAL AND METHODS: From January 2015 to January 2016, nasopharyngeal swabs from 450 children, aged ≤2 years, who had been admitted to the Pediatric Department of the Maputo Central Hospital (HCM) in Mozambique, suffering with SARI were enrolled and tested for influenza and RSV using a real-time PCR assay. RESULTS: Influenza and RSV were detected in 2.4% (11/450) and 26.7% (113/424) of the participants. Children with influenza were slightly older than those infected with RSV (10 months in influenza-infected children compared to 3 months in RSV-infected children); male children were predominant in both groups (63.6% versus 54.9% in children with influenza and RSV, respectively). There was a trend towards a higher frequency of influenza (72.7%) and RSV (93.8%) cases in the dry season. Bronchopneumonia, bronchitis and respiratory distress were the most common diagnoses at admission. Antibiotics were administered to 27,3% and 15,9% of the children with influenza and RSV, respectively. Two children, of whom, one was positive for RSV (aged 6 months) and another was positive for Influenza (aged 3 months) died; both were children of HIV seropositive mothers and had bronchopneumonia. CONCLUSIONS: Our data demonstrated that RSV, and less frequently influenza, occurs in children with SARI in urban/sub-urban settings from southern Mozambique. The occurrence of deaths in small children suspected of being HIV-infected, suggests that particular attention should be given to this vulnerable population. Our data also provide evidence of antibiotics prescription in children with respiratory viral infection, which represents an important public health problem and calls for urgent interventions.

Swine, human or avian influenza viruses differentially activates porcine dendritic cells cytokine profile.

Swine influenza virus (SwIV) is considered a zoonosis and the fact that swine may act as an intermediate reservoir for avian influenza virus, potentially infectious for humans, highlights its relevance and the need to understand the interaction of different influenza viruses with the porcine immune system. Thus, in vitro porcine bone marrow-derived dendritic cell (poBMDCs) were infected with a circulating SwIV A/Swine/Spain/SF32071/2007(H3N2), 2009 human pandemic influenza virus A/Catalonia/63/2009(H1N1), low pathogenic avian influenza virus (LPAIV) A/Anas plathyrhynchos/Spain/1877/2009(aH7N2) or high pathogenic avian influenza virus (HPAIV) A/Chicken/Italy/5093/1999(aH7N1). Swine influenza virus H3N2 infection induced an increase of SLA-I and CD80/86 at 16 and 24h post infection (hpi), whereas the other viruses did not. All viruses induced gene expression of NF-κB, TGF-ß, IFN-ß and IL-10 at the mRNA level in swine poBMDCs to different extents and in a time-dependent manner. All viruses induced the secretion of IL-12 mostly at 24hpi whereas IL-18 was detected at all tested times. Only swH3N2 induced IFN-α in a time-dependent manner. Swine H3N2, aH7N2 and aH7N1 induced secretion of TNF-α also in a time-dependent manner. Inhibition of NF-κB resulted in a decrease of IFN-α and IL-12 secretion by swH3N2-infected poBMDC at 24hpi, suggesting a role of this transcription factor in the synthesis of these cytokines. Altogether, these data might help in understanding the relationship between influenza viruses and porcine dendritic cells in the innate immune response in swine controlled through soluble mediators and transcription factors.

Review: influenza virus in pigs.

Influenza virus disease still remains one of the major threats to human health, involving a wide range of animal species and pigs play an important role in influenza ecology. Pigs were labeled as "mixing vessels" since they are susceptible to infection with avian, human and swine influenza viruses and genetic reassortment between these viruses can occur. After the H1N1 influenza pandemic of 2009 with a swine origin virus, the most recent research in "influenzology" is directed at improving knowledge of porcine influenza virus infection. This tendency is probably due to the fact that domestic pigs are closely related to humans and represent an excellent animal model to study various microbial infectious diseases. In spite of the role of the pig in influenza virus ecology, swine immune responses against influenza viruses are not fully understood. Considering these premises, the aim of this review is to focus on the in vitro studies performed with porcine cells and influenza virus and on the immune responses of pigs against human, avian and swine influenza viruses in vivo. The increased acceptance of pigs as suitable and valuable models in the scientific community may stimulate the development of new tools to assess porcine immune responses, paving the way for their consideration as the future "gold standard" large-animal model in immunology.

Differential interactions of virulent and non-virulent H. parasuis strains with naïve or swine influenza virus pre-infected dendritic cells.

Pigs possess a microbiota in the upper respiratory tract that includes Haemophilus parasuis. Pigs are also considered the reservoir of influenza viruses and infection with this virus commonly results in increased impact of bacterial infections, including those by H. parasuis. However, the mechanisms involved in host innate responses towards H. parasuis and their implications in a co-infection with influenza virus are unknown. Therefore, the ability of a non-virulent H. parasuis serovar 3 (SW114) and a virulent serovar 5 (Nagasaki) strains to interact with porcine bone marrow dendritic cells (poBMDC) and their modulation in a co-infection with swine influenza virus (SwIV) H3N2 was examined. At 1 hour post infection (hpi), SW114 interaction with poBMDC was higher than that of Nagasaki, while at 8 hpi both strains showed similar levels of interaction. The co-infection with H3N2 SwIV and either SW114 or Nagasaki induced higher levels of IL-1ß, TNF-α, IL-6, IL-12 and IL-10 compared to mock or H3N2 SwIV infection alone. Moreover, IL-12 and IFN-α secretion differentially increased in cells co-infected with H3N2 SwIV and Nagasaki. These results pave the way for understanding the differences in the interaction of non-virulent and virulent strains of H. parasuis with the swine immune system and their modulation in a viral co-infection.

Interaction of porcine conventional dendritic cells with swine influenza virus.

Swine influenza virus (SwIV) causes sub-acute or acute respiratory infections on swine farms and pigs can act as "mixing vessels" for new influenza strains. Knowledge of the immune response of SwIV in its natural host, pigs, is very limited. Dendritic cells (DCs) mediate the induction of immunity to pathogens, but their interaction with SwIV has not been fully characterized. Thus, porcine bone marrow derived DCs (poBMDCs) were exposed to a circulating strain of H3N2 SwIV in vitro. Infection of poBMDCs resulted in structures resembling influenza virus inside poBMDCs in vesicles and also free in cytoplasm. Viral progeny was undetectable in supernatant but limited replication was detected in the first 8h after infection. However, viral particles from infected-poBMDCs were able to induce cytopathic effect in susceptible cells only when cell-to-cell interaction was favoured. The data generated in our studies reveal the particular interaction of H3N2 SwIV with conventional DCs.