No description available.

PCR is a rapid, reproducible method for nucleic acid detection. However, this technology displays significant deficiencies when applied in clinical microbiology. This work’s aim was to improve current diagnostics and provide sensitive and quantitative real-time PCRs. Paper I describes the development of a sensitive and specific quantitative real-time PCR for the detection of Streptococcus pneumoniae, based on the Spn9802 DNA fragment. Applied to nasopharyngeal aspirates from 166 pneumonia patients, Spn9802 PCR had a sensitivity of 94% and a specificity of 98%. In Paper II the performance of a ply gene PCR for identification of pneumococcal lower respiratory tract infection (LRTI) was evaluated on bronchoalveloar lavage fluids. At the detection limit 103 genome copies/mL, 89% sensitivity but only 43% specificity was achieved. Paper III shows that S. pneumoniae DNA is detectable in plasma from acutely febrile patients. Sensitivities were low (26-42%) for detection of pneumococcal pneumonia, for bacteraemic pneumococcal pneumonia they were 60-70%. Paper IV describes evaluation of four PCR targets for Haemophilus influenzae detection. A real-time PCR based on the P6 gene was developed and applied to 166 CAP patients, using cut-off of 104 genome copies/mL the assay had a sensitivity of 97% and a specificity of 96%. In paper V, the two real-time PCRs presented in papers I and IV were combined with a PCR for detection of Neisseriae meningitidis. The analytical sensitivity of this multiplex real-time PCR was not affected by using a mixture of reagents and a combined DNA standard (S. pneumoniae/H. influenzae) in single tubes. Applied to 156 LRTI patients, this PCR had sensitivities over 90% for S. pneumoniae and H. influenzae, and specificities of 89% and 96%, respectively. In conclusion, real-time PCR assays are useful for the diagnosis of S. pneumoniae and H. influenzae. They enable detection after antibiotic installation, and quantification increases the etiological specificity of pneumonia.

京都大学 / 0048 / 新制・課程博士 / 博士(社会健康医学) / 甲第20623号 / 社医博第81号 / 社新制||医||9(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 木原 正博, 教授 中川 一路, 教授 平家 俊男 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM

IV. ABSTRACT The human metapneumovirus is a novel paramyxovirus associated with acute respiratory infections in children, adults, elderly and immunocompromised individuals. It has a worldwide distribution and the prevalence range between 1.5% to 25% in individuals with respiratory infections. Based on phylogenetic analysis 2 distinct genetic groups (A and B) that are sub-divided into four subgroups (A1, A2, B1 and B2) have been shown to circulate. Until recently, there was no information on the molecular epidemiology and the clinical characteristics of the hMPV in Africa, including South Africa, a region with a high prevalence of paediatric human immunodeficiency virus type-1 (HIV) infection. The molecular epidemiology and clinical characteristics of the hMPV in South Africa was investigated over a three period (2000-2002) in children hospitalized with lower respiratory tract infection. The children were part of a cohort participating in a phase 3 clinical trial investigating the efficacy of a 9-valent-pneumocococcal protein-polysaccharide conjugate vaccine (PCV). The objectives of the study were: i. to investigate the molecular epidemiology of hMPV in South Africa; ii. characterize the burden of hMPV disease and determine the clinical features of hMPV-LRTI in children infected and not infected by HIV; iii. probe the role of Streptococcus pneumoniae in the pathogenesis of hMPV-LRTI. The overall prevalence of hMPV in children hospitalized with lower respiratory tract infections (LRTI) was 7.4%. The mean age of children with hMPV associated LRTI (hMPV-LRTI) in South Africa was 13.3 months (range 1.4-49.2 months), with HIV infected children being older than children not infected with HIV (mean [range] 17.6 [4.5-44.3] vs. 12.3 [1.4-49.2] months; P=0.007). The incidence of hMPV-LRTI was 5.0 (95%C.I.3.3-7.5) fold greater in HIV infected children (incidence rate: 2 504 [95%C.I. 1 683-3 577] per 100 000) than in HIV uninfected children (incidence rate: 505 [95%C.I. 409-618] per 100 000, P<0.0001). Human metapneumovirus was identified less frequently than RSV but more commonly than other studied respiratory viruses. The double-blind PCV-9 vs. placebo controlled trial was used to probe the role of pneumococcal co-infections contributing to the pathogenesis of severe hMPV-LRTI. The incidence of hospitalization for hMPV-LRTI was reduced by 46% (95%, CI, 25-63; P=0.0002) in PCV-9 vaccinees compared to placebo recipients. This inferred that coinfection with Streptococcus pneumoniae was integral to the pathogenesis of hMPV-LRTI requiring hospitalization. Both groups of the hMPV circulated during the three year period including concurrent circulation of multiple subtypes of the virus. There was a transition from group B to group A subtype virus as the dominant circulating virus over sequential years. Sequence analysis of the two attachment glycoproteins (F and G), showed the F gene protein to be highly conserved, in contrast the attachment protein gene (G protein) was highly variable particularly in the extracellular domain between lineages. Repeat hMPV-LRTI by either homologous or heterologous strains within 3 months of each other suggested that natural infection did not confer complete immunity to hMPV. The present study demonstrated that hMPV is a leading pathogen associated with LRTI among children in Africa and indicated that occult pneumococcal co-infections’ were integral in the pathogenesis of hMPV-LRTI requiring hospitalization. Additionally, this is the first study to have characterized the molecular epidemiology of hMPV in Africa and provides insight as to issues that may exist regarding the design of an hMPV vaccine.

Submitted by VINÍCIUS ATHAYDES CANELLO null (vinaocanello@hotmail.com) on 2017-03-16T11:28:58Z No. of bitstreams: 1 Tese Versão Final.pdf: 4376586 bytes, checksum: 13d4cc1c29f43d7c4deb2102a7b48543 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2017-03-22T16:42:38Z (GMT) No. of bitstreams: 1 canello_va_dr_jabo.pdf: 4376586 bytes, checksum: 13d4cc1c29f43d7c4deb2102a7b48543 (MD5) / Made available in DSpace on 2017-03-22T16:42:38Z (GMT). No. of bitstreams: 1 canello_va_dr_jabo.pdf: 4376586 bytes, checksum: 13d4cc1c29f43d7c4deb2102a7b48543 (MD5) Previous issue date: 2017-02-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O grande desafio do sistema de defesa respiratório é a manutenção dos animais em baias. Pois, devido a diversos fatores, acaba por aumentar as chances do desenvolvimento de afecções respiratórias e a qualidade do material utilizado como cama é fator agravante. Diante disto, três grupos com 5 equinos cada foram submetidos a 45 dias sob o mesmo manejo, sendo dois grupos estabulados com diferentes tipos de cama, um com maravalha esterilizada (ME) e o outro com maravalha não esterilizada (MNE), e o terceiro grupo a pasto (Pasto). Foram realizadas análises do lavado broncoalveolar (LBA) (celularidade e marcadores de estresse oxidativo) e hemograma antes do início do manejo (Basal) e posteriormente a cada 15 dias (M15, M30 e M45). Também foi avaliada a presença de gêneros fúngicos nas amostras de cama, e do feno utilizado na alimentação dos animais. Os hemogramas permaneceram dentro dos valores da normalidade. Os valores obtidos de malondialdeído (MDA) e ácido úrico no LBA não apresentaram diferença entre os momentos e grupos avaliados. A vitamina C no LBA apresentou queda em seus valores em M30. Os três grupos apresentaram queda nas concentrações de glutationa reduzida em M30, tendo havido diferença significativas entre os grupos Pasto e MNE. Os grupos ME e MNE apresentaram queda nos valores de glutationa oxidada em M45, já o grupo Pasto apresentou queda constante a partir de M15, com diferença significativa em relação ao grupo ME em M30. A superóxido dismutase apresentou aumento em M30 no grupo MNE, levando a diferença significativa em relação aos grupos Pasto e ME. A glutationa peroxidase no LBA apresentou queda significativa no grupo ME em M45. Quanto a celularidade do LBA a contagem de células nucleadas totais e eosinófilos não apresentaram diferenças significativas. O grupo ME apresentou elevação nos valores de neutrófilos em M30, levando a diferença significativa em relação aos grupos MNE e Pasto, já o grupo MNE apresentou queda significativa em M45. Os grupos ME e MNE apresentaram queda nos valores de linfócitos no LBA em M30, já o grupo Pasto apresentou queda em M15. O grupo Pasto apresentou aumento dos macrófagos no LBA em M15 e M30. As análises das amostras de cama e feno apresentaram baixas porcentagens de gêneros fúngicos. Grande parte das alterações apresentadas ocorreram em M30, momento em que foram registradas as menores temperaturas e maiores velocidades dos ventos durante todo período experimental, o que possivelmente levou a um desequilíbrio oxidativo pontual, com pequenas variações na celularidade do LBA. Acredita-se que o manejo, as boas condições de higiene e ventilação das baias tenham contribuído para que não houvesse o desenvolvimento de alterações inflamatórias no sistema respiratório dos animais avaliados. Deste modo, podemos concluir que não houve diferenças significativas na manutenção dos animais nos diferentes tipos de cama em relação a resposta inflamatória, estresse oxidativo e desenvolvimento fúngico. / The great challenge of the respiratory defense system is the maintenance of animals in stalls, which due to several factors ends up increasing the chances of development of respiratory diseases. The quality of the material used as bed is an aggravating factor. Three groups of 5 horses were submitted to 45 days under the same management, and two groups were housed with different types of beds, one with sterilized wood shaving (ME) and the other with unsterilized wood shaving (MNE), and the third group was maintened in the pasture. Bronchoalveolar lavage fluid (BALF) and hemoglobin analyzes were performed before baseline and then every 15 days (M15, M30 and M45). It was also evaluated the possible presence of fungal genera in bed samples, and in hay used in animal feeding. The hemograms remained within normal values. The values of malondialdehyde (MDA) and uric acid in BALF showed no difference between the moments and groups evaluated. Vitamin C in BALF showed a decrease in M30 values. The three groups showed a decrease in the concentrations of glutathione reduced in M30, and there were significant differences between the groups pasture and MNE. The ME and MNE groups showed a decrease in the values of oxidized glutathione in M45, whereas the pasture group presented a constant drop from M15, with a significant difference in relation to the ME group in M30. Superoxide dismutase increased in M30 in the MNE group, leading to a significant difference in relation to the pasture and ME groups. Glutathione peroxidase in BALF showed a significant decrease in the ME group in M45. As for the cellularity of BALF, total nucleated and eosinophil counts did not showed significant differences. The ME group presented elevation in neutrophil values in M30, leading to a significant difference in relation to the MNE and pasture groups, whereas the MNE group presented a significant decrease in M45. The ME and MNE groups presented a decrease in lymphocyte values in the BALF in M30, whereas the pasture group presented a decrease in M15. The pasture group presented increase of the macrophages in the BALF in M15 and M30. Bed and hay samples showed low percentages of fungal genera. Most of the alterations presented occurred in M30, at which time the lowest temperatures were recorded throughout the experimental period, possibly leading to a punctual oxidative imbalance, with small variations in BALF cellularity. It is believed that management, good conditions of hygiene and ventilation of the boxes contributed to the no development of inflammatory changes in the respiratory system of the animals evaluated. Thus, we can conclude that there were no significant differences in the maintenance of the animals in the different types of bed in relation to the inflammatory response, oxidative stress and fungal development.

The aim of this thesis was to analyse possible effects of prenatal arsenic exposure on foetal and infant health. The setting is Bangladesh, where two cohorts were studied, both part of a health and demographic surveillance system in Matlab. A historical cohort 1991-2000 included 29,134 pregnant women with information on drinking water sources and arsenic testing of tube well water. A prospective cohort study included pregnant women 2002 - 2003 where urinary arsenic concentrations were assessed twice during pregnancy; 2,924 women and their pregnancy outcomes were evaluated for foetal loss, perinatal and infant mortality; 1,578 mother-infant pairs were analysed for size at birth; and 1,552 were analysed for morbidity during infancy. Women exposed to arsenic levels ≥ 50 µg/L in water had an increased risk of foetal loss and infant death in comparison with women exposed to arsenic levels &lt; 50 µg/L. These findings were confirmed in the prospective cohort study. Women with urine arsenic concentrations at the 5th quintile had 62% increased risk of spontaneous abortion (OR 1.62, 95% CI 1.04 - 2.55) in comparison with women who had arsenic concentrations at the 1st quintile level. Increased risks of perinatal morality (RR 3.01, 95% CI 1.07 - 8.45) and infant mortality (RR 5.01; 95% CI: 1.41 - 17.84) were also observed at the 5th quintile of exposure. Significant negative dose-effect associations were found between arsenic exposure and birth weight, head and chest circumferences at a relatively low level of exposure (&lt;100 µg/L in urine). In this range of exposure birth weight decreased by 1.68 g (SE 0.62) for each 1 µg/L increase of arsenic in urine. In comparison with exposure at the 1st quintile level the risk of lower respiratory tract infection was significantly increased (RR 1.68, 95% CI 1.35-2.07) for women who had urinary arsenic concentrations at the 5th quintile level. The risk was also increased for diarrhoeal diseases. The study findings highlight the negative effects of arsenic exposures on pregnancy outcomes and infant health. Mitigation programs need to be strengthened and women of reproductive ages should be prioritized in arsenic affected regions worldwide.

Acute lower respiratory tract infection (ALRI) is a major cause of paediatric morbidity and mortality, annually accounting for approximately 2 million childhood deaths worldwide of which up to 90% resides in the developing world. In 12-39% of ALRI cases no aetiological agent is identified, despite comprehensive investigations, thus suggesting that additional unknown agents may be involved. Since 2001 a number of new viruses have been identified that may account for some of these cases including human metapneumovirus (hMPV), human bocavirus (hBoV), and two new coronaviruses (hCoV) NL63 and HKU1. The contribution of the recently identified respiratory viruses to annual seasonal lower respiratory tract disease in Sub-Saharan Africa where human immunodeficiency virus infections may exacerbate respiratory infections is not fully understood. In addition, the role and disease association of many of these viruses as primary or co-infecting pathogens, as well as the underlying factors that may determine the pathogenesis of these viruses, is not yet well defined. Quantitative multiplex real-time RT-PCR assays were developed and validated for the detection of 13 well recognized and newly identified viral causes of ALRI, including respiratory syncytial virus (RSV), influenza viruses A and B, parainfluenza virus (PIV) types 1, 2, and 3, adenovirus, hMPV, hBoV and hCoV-NL63, -HKU1, -229E, and -OC43. The newly designed assays were subsequently used to facilitate the investigation of the contribution of respiratory viruses in patients requiring hospitalisation or attending outpatient visits in public sector hospitals serving the Pretoria area, South Africa. During 2006, the prevalence of the aforementioned respiratory viruses was determined by investigating the well recognized viruses previously diagnosed by routine immunofluorescence assays (IFA) in 737 respiratory specimens as well as viruses retrospectively detected by multiplex real-time RT-PCR in a sample group of 319 specimens. The epidemiology and disease association of these respiratory viruses in children who were predominantly less than 5 years of age with acute respiratory tract infections was investigated. Specimens were received from 2 public sector hospitals in Pretoria, South Africa. In addition, the disease association of each virus as a single or co-infection in human immunodeficiency virus (HIV) infected/exposed and HIV-uninfected children as well as the role of viral load was investigated. The multiplex assays could detect 2.5-25 recombinant plasmid DNA/RNA (in vitro transcribed) copies/μl, with a co-efficient of variation of less than 3.1%. Validation on 91 known positive respiratory specimens indicated similar specificity to IFA or single-round PCRs used in the initial identification of the viruses. Application of the multiplex assays to IFA negative specimens improved the detection of respiratory viruses by up to 44%. In children less than 5 years of age RSV was identified in 35.1%, followed by PIV 3 (8.3%); adenovirus (5.6%); influenza A (4.2%); hMPV (4.2%); hBoV (3.8%); hCoV-NL63 (1.6%); influenza B (1.0%); and PIV1, PIV2, hCoV-OC43, hCoV-229E, hCoV-HKU1 in less than 1% of cases. Co-infections were more common for the new viruses ranging from 58% of hMPV cases to 84% for hCoV-NL63 relative to 27% of RSV cases. Viruses were most frequently identified in children <1-year. RSV activity peaked in autumn and winter, PIV 3 in spring, while influenza A and B were mostly detected in winter. The observed seasonal distribution of hBoV and hMPV was less defined compared to traditional viruses, with both viruses showing variability over the two years. Comparable hospitalisation rates were observed for RSV, hMPV, PIV 3 and adenovirus, where approximately 60% of infected children were hospitalised. In addition, a high frequency of hospitalisations was observed in patients for both hMPV and hBoV in HIV-infected/exposed children. Co-infections occurred at higher frequencies with the new viruses, were more frequently associated with severe disease and were frequent in HIV-infected/exposed patients. Viral load was associated with severe RSV disease (p=0.014) however no significant association was observed for the new viruses as single infections. However, where hMPV occurred as a co-infection, higher viral loads of either hMPV or co-infecting agents occurred in severe cases. This association was also observed for hBoV. Most cases of hCoV-NL63 and hCoV-OC43 were co-infections in hospitalised patients. The newly developed multiplex assays demonstrates an improved sensitivity and scope of detecting respiratory viruses relative to routine antigen detection assays while the quantitative utility may facilitate investigation of the role of co-infections and viral load in respiratory virus pathogenesis. RSV remains the most significant viral cause of paediatric ALRI in South Africa. Viruses not currently included in routine diagnostic assays collectively contributed to 11% of ALRI cases in children <2-years in South African hospitals. / Dissertation (MSc)--University of Pretoria, 2010. / Medical Virology / unrestricted

Despite advances in health promotion through efforts to reduce tobacco smoking, tobacco-related health conditions have continued to be significant. Exposure to secondhand smoke has been identified as a health risk also in addition to infant health risks related to maternal smoking. In contrast, breastfeeding has been found to promote infant health and is strongly encouraged. Despite literature supporting both of these statements, the combined effects of both breastfeeding and maternal smoking on infant wellbeing have not been delineated. Otitis media represents a common health problem among infants and young children. Tobacco exposure has been shown to increase its incidence while breastfeeding has been shown to reduce its occurrence. In the current study, a consecutive sample of all infants less than 5 years of age with otitis media and breastfed for at least 6 months was collected from a busy urban clinic for analysis. A survey tool was administered to those meeting study criteria. Primary analysis examined the odds ratio of developing otitis media among breastfed infants between those whose mothers smoked tobacco and those whose mothers did not. As a result, the association between the protective effects of breastfeeding and the detrimental effects of maternal smoking was evaluated in relation to the development of otitis media. Secondary variables including demographics, family history, past medical and birth history, and secondhand smoke exposure were also assessed. Results failed to demonstrate a significant difference in otitis media between the 2 cohorts in this study, and of the secondary variables, only cranio-facial deformities and/or a family history of these conditions resulted in higher otitis media occurrence. Further study with larger populations with higher tobacco use rates may offer additional insights into this matter.

Background: Humanmilk oligosaccharides (HMOs) support and concurrently shape the neonatal immune system through various mechanisms. Thereby, they may contribute to lower incidence of infections in infants. However, there is limited evidence on the role of individual HMOs in the risk of otitis media (OM), as well as lower and upper respiratory tract infections (LRTI and URTI, respectively) in children up to 2 years. Objective: To investigate whether individual HMO concentrations measured at 6 weeks of lactation were associated with risk of OM, LRTI or URTI up to 2 years in breastfed infants. Associations with OM, LRTI and URTI were determined for the most prominent human milk oligosaccharides including 13 neutral, partly isomeric structures (trioses up to hexaoses), two acidic trioses, and lactose. Design: HMO measurements and physician reported data on infections were available from human milk samples collected at 6 weeks postpartum (n = 667). Associations of HMOs with infections were assessed in crude and adjusted models using modified Poisson regression. Results: Absolute concentrations (median [min, max], in g/L) of 2′-fucosyllactose (2′-FL) tended (p = 0.04) to be lower, while lacto-N-tetraose (LNT) was higher in the milk for infants with OM in the 1st year of life (p = 0.0046). In the milk of secretor mothers, LNT was significantly higher in the milk for infants with OM (RR [95% CI]: 0.98 [0.15, 2.60]) compared to infants without OM (RR [95% CI]: 0.76 [0.14, 2.90]) at 1 year (p = 0.0019). No statistically significant milk group differences and associations were observed for OM, LRTI, and URTI (p > 0.0031). Conclusion: Our findings suggest that neither prominent neutral individual HMOs (ranging from 2′-FL to LNDFHs) nor acidic human milk sialyllactoses or lactose are significantly associated with a reduced or increased risk of infections in infants up to 2 years of age. Further research is needed to determine whether specific HMOs could potentially reduce the incidence or alleviate the course of distinct infections in early life.

Made available in DSpace on 2016-01-26T12:51:26Z (GMT). No. of bitstreams: 1 joaobatistasalomaojunior_tese.pdf: 726701 bytes, checksum: be09a3fcaa3d491c8ac2601eb72d7961 (MD5) Previous issue date: 2008-02-08 / Acute lower respiratory tract disease (ALRTD) accounts for high infantile mortality and morbidity rate worldwidely. Respiratory syncytial virus (RSV) is frequently found among pathogens. Objectives: The objectives were: 1) to evaluate the RSV frequency in children from 0 to 6 years hospitalized due to acute lower respiratory disease in São José do Rio Preto, SP; 2) to characterize the virus seasoning in this city and 3) to verify possible association among epidemiologic, clinical and diagnostic data with this viral agent. Casuistic and Method: From May 2004 to September 2005, 278 children aged from 0 to 6 years with ALRTD were studied. They have contracted the disease in the community, hospitalized in the children s ward, emergency room and Pediatric Intensive Care Unit of Hospital de Base, São José do Rio Preto. They were asymptomatic in a 7-day period before the beginning of the disease. Questionnaires were used for the children's characterization and their clinical presentation. Samples of nasopharyngeal secretion were collected to identify RSV, using reverse transcription polymerase chain reaction (RT-PCR). Results: The results showed that in the 290 hospitalizations of ALRTD, RSV was positive in 29.3%. ALRTD was more frequent in infants (average = 13.5 months) and male (57.6%). RSV was more frequent in bronchiolitis cases (64%). RSV+ infections were more frequent in the first year of life (35%). In RSV + infections, pneumonia frequency varied from 19.5 to 26.2% in the studied age groups; acute wheezing was observed in 31.8% of children aged over 2 years; bronchiolitis was registered in 62.5% of the children younger than 1 year; pneumonia with pleural effusion was noticed in 18.7% of the children aged over 2 years. Conclusions: The frequency of RSV in children from 0 to 6 years hospitalized due to ALRTD was 29.3% in São José do Rio Preto, SP. The ALRTD were more frequent between June and November 2004. In 2005, the hospitalizations occurred mainly starting from March decreasing in September. There was RSV prevalence in children younger than 2 years, male and with bronchiolitis. The RSV frequency in the hospitalizations was higher in 2004 than in 2005. In the RSV+ infections, the cases of pneumonia had similar occurrence in the studied age groups. There was reduction of the RSV frequency as age increases in the cases of pneumonia with pleural effusion and increase in the cases of acute wheezing; in bronchiolitis most of the RSV+ cases occurred in children younger than1 year. The clinical and radiological data obtained did not allow the proper identification of the infection by RSV. Laboratory examination by means of RT-PCR was necessary to identify it. / As doenças agudas do aparelho respiratório inferior (DARI) são responsáveis por altos índices de mortalidade e morbidade infantil em todo mundo. Dentre os patógenos predominantes encontra-se o vírus sincicial respiratório (VSR). Objetivos: Os objetivos foram: 1) avaliar a freqüência do VSR em crianças de 0 a 6 anos hospitalizadas por DARI em São José do Rio Preto, SP; 2) caracterizar a sazonalidade do vírus nessa cidade e 3) evidenciar possível associação de dados epidemiológicos, clínicos e diagnósticos e este agente viral. Casuística e Método: No período de maio de 2004 a setembro de 2005 foram estudadas 278 crianças de 0 a 6 anos com DARI adquirida na comunidade, internadas na enfermaria, emergência e Unidade de Terapia Intensiva Pediátrica do Hospital de Base de São José do Rio Preto, que estavam assintomáticas por um período de 7 dias antes do início da doença. Foram utilizados questionários para caracterização das crianças e do quadro clínico. Para identificação do VSR foram coletadas amostras de secreção de nasofaringe, utilizando-se a técnica de Reverse Transcription Polymerase Chain Reaction (RT-PCR). Resultados: Os resultados mostraram que nas 290 internações por DARI, o VSR foi positivo em 29,3%. DARI foi mais freqüente em lactentes (mediana = 13,5 meses) e do gênero masculino (57,6%). O VSR foi mais freqüente nos casos de bronquiolite (64%). As infecções VSR+ foram mais freqüentes no primeiro ano de vida (35%). Nas infecções VSR+, a freqüência de pneumonia variou de 19,5 a 26,2% nas faixas etárias estudadas; em 31,8% das crianças maiores de 2 anos observou-se sibilância aguda; bronquiolite foi registrada em 62,5% das crianças menores de 1 ano; pneumonia com derrame pleural foi notada em 18,7% das crianças maiores de 2 anos. Conclusões: A freqüência do VSR em crianças de 0 a 6 anos hospitalizadas por DARI em São José do Rio Preto, SP, foi 29,3%. As DARI foram mais freqüentes entre junho e novembro de 2004. Em 2005, as internações ocorreram principalmente a partir de março, com queda em setembro. Houve predomínio do VSR em crianças de 0 a 2 anos, do gênero masculino e com bronquiolite. A freqüência do VSR nas internações foi maior em 2004 que em 2005. Nas infecções VSR+ os casos de pneumonia tiveram ocorrência semelhante nas faixas etárias estudadas. Houve redução da freqüência do VSR com aumento da idade nos casos de pneumonia com derrame pleural e aumento nos casos de sibilância aguda; na bronquiolite a maioria dos casos VSR+ ocorreu em crianças menores de 1 ano. Os dados clínicos e radiológicos encontrados não permitiram a identificação correta da infecção pelo VSR, havendo necessidade do exame laboratorial pela técnica RT-PCR para sua identificação.