RESUMO
A cross-sectional study was carried out, from November 2007 to March 2008, to estimate the prevalence of and to determine risk factors associated with bovine syncytial respiratory virus (BRSV) and parainfluenza 3 virus (PIV3) in dual-purpose herds in Colima, México. One hundred and seventy-six sera from 33 herds for PIV3 and 232 sera from 44 herds for BRSV were used. Sera were analyzed by indirect ELISA for the detection of antibodies against BRSV and PIV3 in cattle herds to determine the seroprevalence of respiratory diseases. The apparent and true prevalences for PIV3 were 60.8% and 54.4% and for BRSV 52.2% and 50.8%, respectively. The percentage of herds showing at least one positive animal was 78.7% for PIV3, and 93.2% for BRSV. Age (≤ 12, 13-48, and >48 months old) and respiratory signs (no, yes) showed significant association (P < 0.05) with PIV3 and age with BRSV. This study showed that animals were exposed to both viruses and that age was the main risk factor. The need to establish new vaccination plans to effectively protect cattle against those infections in the state of Colima, Mexico is suggested.
Assuntos
Anticorpos Antivirais/sangue , Doenças dos Bovinos/epidemiologia , Vírus da Parainfluenza 3 Bovina/isolamento & purificação , Infecções por Vírus Respiratório Sincicial/veterinária , Vírus Sincicial Respiratório Bovino/isolamento & purificação , Infecções por Respirovirus/veterinária , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática/veterinária , México/epidemiologia , Vírus da Parainfluenza 3 Bovina/imunologia , Prevalência , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/microbiologia , Vírus Sincicial Respiratório Bovino/imunologia , Infecções por Respirovirus/epidemiologia , Infecções por Respirovirus/microbiologia , Fatores de Risco , Estudos SoroepidemiológicosRESUMO
We have examined the function of class I MHC-restricted cytotoxic T cells in experimental respiratory syncytial virus (RSV) infection of BALB/c mice by transfer of T cell line MJC-A2 and CTL clone E8a into RSV-infected mice. The T cell line cleared pulmonary RSV infection within 5 d in persistently infected gamma-irradiated mice, but caused acute respiratory disease. This was only seen in infected mice and was often lethal after transfer of greater than 3 x 10(6) CTL. Lower numbers of CTL produced less severe disease but still cleared lung RSV, albeit over a longer time course (up to 10 d). Clearance of lung RSV in immunocompetent mice by the T cell line and CTL clone was again accompanied by acute and sometimes lethal respiratory disease. Bronchoalveolar lavage showed severe lung hemorrhage and frequent neutrophil efflux in mice with CTL-augmented disease.
Assuntos
Pulmão/patologia , Infecções por Respirovirus/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Células Clonais , Dimercaprol , Imunização Passiva , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Vírus Sinciciais Respiratórios/imunologia , Infecções por Respirovirus/microbiologia , Infecções por Respirovirus/patologiaRESUMO
We have used the technique of ribonuclease protection to define genomic variation among circulating isolates of subgroup A respiratory syncytial (RS) virus. RNAs extracted from HEp-2 cells infected with strains to be analyzed were hybridized with a 32P-labeled RNA probe corresponding to the RS virus G glycoprotein (A2 strain). Areas of nonhomology were detected by cleavage with ribonuclease A. Using this technique, multiple distinct RNA cleavage patterns could be distinguished among viral isolates recovered from infants residing in the same metropolitan area and infected during the same epidemic season. Epidemiologically related isolates (from coinfected twins, from infants infected during a nosocomial outbreak at an extended care facility, and from institutionalized adults infected during an outbreak) yielded identical patterns. In two separate outbreaks, differences in cleavage patterns among certain isolates corresponded to epidemiologically significant differences among the individuals from whom the isolates were recovered. We conclude that substantial genomic heterogeneity exists among circulating isolates of subgroup A RS virus. Ribonuclease protection can be used as a molecular fingerprinting tool for expanded studies of the molecular epidemiology of this virus.
Assuntos
Mapeamento de Nucleotídeos , Sondas RNA , RNA Viral/isolamento & purificação , Vírus Sinciciais Respiratórios/genética , Infecções por Respirovirus/epidemiologia , Ribonucleases , Adulto , Surtos de Doenças , Variação Genética , Humanos , Lactente , Missouri , Desnaturação de Ácido Nucleico , Hibridização de Ácido Nucleico , Mapeamento de Nucleotídeos/métodos , RNA Viral/genética , Vírus Sinciciais Respiratórios/crescimento & desenvolvimento , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções por Respirovirus/genética , Infecções por Respirovirus/microbiologiaRESUMO
The etiology and epidemiology of croup were studied in a pediatric group practice over an 11-year period, 1964 to 1975. Croup was diagnosed in 951 instances in 6,165 cases of lower respiratory tract infection (LRI) studied. As census figures of the practice clientele were available, attack rates were calculated. The incidence of total LRI was highest in the first year of life. In contrast, the attack rate for croup was highest in the second year of life; the rate declined gradually after that age. Croup was not diagnosed in the first month of life. Boys were 1.43 times more likely to develop croup than were girls. Three hundred sixty agents were isolated from the 951 croup cases. The parainfluenza viruses accounted for 74.2% of all isolates; 65% of the parainfluenza isolates were classified as parainfluenza virus type 1. Respiratory syncytial virus, influenza viruses A and B, and Mycoplasma pneumoniae were the only other agents isolated in appreciable numbers. The propensity of various agents to produce croup symptoms in children with LRI due to specific microorganisms was 58% for parainfluenzae type 1,60% for parainfluenzae type 2, and 29% for parainfluenzae type 3; similar figures for the other agents varied from 5% to 16%. The role of the various agents in the etiology of croup varied with patient age and depended on the propensity of the agent to produce the croup syndrome and the frequency of isolation of the agent at that age. The parainfluenza viruses were the most important croup agents at all ages; respiratory syncytial virus caused croup in children less than 5 years of age whereas the influenza viruses and M pneumoniae were significant causes of croup only in children more than 5 to 6 years old. Croup occurred predominately in late fall and early winter, times when the parainfluenza viruses, especially type 1, occurred most frequently. The epidemiology of croup differs from that of bronchiolitis, pneumonia, and tracheobronchitis; knowledge of this should be helpful to the clinician caring for children with LRI.
Assuntos
Crupe/epidemiologia , Laringite/epidemiologia , Infecções por Paramyxoviridae/epidemiologia , Infecções por Respirovirus/epidemiologia , Fatores Etários , Criança , Pré-Escolar , Crupe/microbiologia , Feminino , Humanos , Lactente , Masculino , Infecções por Paramyxoviridae/microbiologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Respirovirus/isolamento & purificação , Infecções por Respirovirus/microbiologia , Estações do Ano , Fatores SexuaisRESUMO
Seventy-four children ages 1 to 9 years hospitalized because of severe pneumonia were investigated using blood cultures, lung aspirates, nasopharyngeal aspirates, serology and antigen detection procedures. A bacterial infection was identified in 57 (77%), a viral infection was seen in 25 (34%) and 18 (24%) had mixed viral-bacterial infections. The bacterial pathogens most frequently identified were Streptococcus pneumoniae and Haemophilus influenzae found in 61 and 15% of patients, respectively. The viral pathogen most frequently recovered was respiratory syncytial virus (12%). Evidence of Chlamydia pneumoniae strain TWAR and Mycoplasma pneumoniae infection was found in 12 and 4% of cases, respectively. Overall a potential pathogen was identified in 60 (81%) children, with evidence of polymicrobial infection in 30 cases (40.5%). The study provides information on the relative role of different infectious agents in the etiology of severe pneumonia in children in a developing country.
Assuntos
Infecções Bacterianas/microbiologia , Pneumonia Viral/microbiologia , Pneumonia/microbiologia , Doença Aguda , Criança , Pré-Escolar , Infecções por Chlamydia/microbiologia , Feminino , Gâmbia , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/isolamento & purificação , Humanos , Lactente , Masculino , Pneumonia Pneumocócica/microbiologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções por Respirovirus/microbiologiaRESUMO
Acute lower respiratory illnesses were prospectively investigated in a cohort of 1246 healthy infants who were enrolled at birth in the Tucson Children's Respiratory Study and followed through the first 3 years of life. Respiratory syncytial virus (RSV) infection was documented by culture, antigen detection or both in 276 episodes. In 21 (7.6%) of these 276, other viruses were simultaneously detected. Further serologic studies of 50 episodes in which RSV had been found increased the apparent viral codetection rate to 24%. When culture results for Chlamydia trachomatis and Mycoplasma pneumoniae were also considered, the rate of codetection was found to be 10.9% (30 of 276); this increased to 28% for the subgroup of episodes (14 of 50) that was further studied serologically. Illnesses associated with more than one agent were not significantly different from those involving RSV alone, with respect to month of onset, age at illness, illness type or duration of illness. We conclude that when RSV has been detected in previously healthy infants, routine searches for the concomitant presence of other viruses are usually not warranted.
Assuntos
Vírus Sinciciais Respiratórios , Infecções Respiratórias/microbiologia , Infecções por Respirovirus/microbiologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Infecções Respiratórias/diagnóstico , Infecções por Respirovirus/complicações , Infecções por Respirovirus/diagnóstico , Testes Sorológicos , Viroses/diagnóstico , Viroses/microbiologiaRESUMO
Ninety infants less than 1 year of age with pneumonia and 43 control infants were investigated for viral and chlamydial infection with the use of culture and serology and for bacterial infection with the use of blood cultures, lung aspirates, antibody assays and antigen detection procedures. One or more potential pathogens were identified in 62 (69%) cases with pneumonia and in 12 (28%) controls. Infection by respiratory viruses was identified in 42 (49%) cases and in 8 (19%) controls. Respiratory syncytial virus was the commonest pathogen identified and was found in 32 cases (37%). Bacterial infections were also common, being found in 27 (30%) cases and 3 (7%) controls, and predominantly involved Streptococcus pneumoniae (20%) or Haemophilus influenzae (11%). Bacterial infections were associated with raised white blood cell counts and were identified more often by antigen detection procedures (68%) than by culture of blood or lung aspirates (34%) or by serology (33%). Mixed viral-bacterial infections were identified in 13 cases (15%). Infection with Chlamydia trachomatis was diagnosed in 2 infants with acute lower respiratory tract infection and in 1 control infant.
Assuntos
Infecções Bacterianas/microbiologia , Pneumonia Viral/microbiologia , Pneumonia/microbiologia , Doença Aguda , Estudos de Casos e Controles , Infecções por Chlamydia/microbiologia , Chlamydia trachomatis/isolamento & purificação , Infecções por Citomegalovirus/microbiologia , Feminino , Gâmbia , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/isolamento & purificação , Humanos , Umidade , Lactente , Recém-Nascido , Masculino , Pneumonia Pneumocócica/microbiologia , Chuva , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções por Respirovirus/microbiologia , Estações do AnoRESUMO
Nasopharyngeal aspirates were obtained on admission from 614 patients younger than 2 years of age who were hospitalized in a ward for acute respiratory infections from June 1988 through October, 1989, in Santiago, Chile. Patients in two rooms were followed during the cold seasons by sampling aspirates every other day during the child's entire hospital stay. Clinical features were recorded daily. Indirect monoclonal immunofluorescent assay and isolation in HEp-2 were used for respiratory syncytial virus (RSV) diagnosis. The mean RSV detection rate was 39% at the time of admission, ranging from 8% in April, 1989, to 62% in July, 1988. During the cold months 43 of 288 (15%) nosocomial RSV cases were detected. Pneumonia and wheezing bronchitis were the principal diagnoses of both groups admitted, whether they were shedding RSV or not. It is concluded that RSV plays a major role in admissions for acute respiratory infections, as well as in nosocomial infections, in Santiago. Because clinical features do not allow one to differentiate viral from bacterial acute respiratory infections, the importance of rapid viral diagnosis is emphasized.
Assuntos
Infecção Hospitalar/epidemiologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções Respiratórias/epidemiologia , Infecções por Respirovirus/epidemiologia , Chile/epidemiologia , Infecção Hospitalar/microbiologia , Imunofluorescência , Humanos , Lactente , Nasofaringe/microbiologia , Infecções Respiratórias/microbiologia , Infecções por Respirovirus/microbiologia , Estações do AnoRESUMO
A natural plant product, SP-303, was administered by small-particle aerosol to influenza A/HK virus-infected mice and RSV-infected cotton rats. Aqueous SP-303 at 2 mg/ml in the Collison nebulizer reservoir generated an aerosol with an output of 26 micrograms/l and a particle size distribution of 1.4 microns +/- 4.6 (MMAD +/- GSD). SP-303 at a dosage of 0.5-9.4 mg/kg per day administered for 3-4 days significantly increased both the rate and duration of survival of mice lethally infected with influenza A/HK virus. SP-303 was toxic to mice at 16 mg/kg per day as indicated by weight loss and a decrease in the duration of survival compared to control animals. From these data, a maximum therapeutic index (T.I.) of 12 was calculated. SP-303 given 3-4 days at dosages of 1.3-9.8 mg/kg per day was effective in reducing the pulmonary titer of RSV in infected cotton rats. However, at the 18.7 mg/kg per day dose a significant weight loss compared to control animals was observed; a T.I. of < or = 14 was estimated. These experiments demonstrate that aerosol administration of SP-303 was effective in the treatment of influenza A-infected mice and of RSV-infected cotton rats.
Assuntos
Antivirais/farmacologia , Catequina/análogos & derivados , Vírus da Influenza A , Influenza Humana/tratamento farmacológico , Vírus Sinciciais Respiratórios , Infecções por Respirovirus/tratamento farmacológico , Administração por Inalação , Aerossóis , Animais , Antivirais/farmacocinética , Biopolímeros , Catequina/farmacocinética , Catequina/farmacologia , Relação Dose-Resposta a Droga , Humanos , Influenza Humana/microbiologia , Camundongos , Camundongos Endogâmicos ICR , Extratos Vegetais/farmacologia , Ratos , Infecções por Respirovirus/microbiologia , Equivalência TerapêuticaRESUMO
SP-303, a naturally occurring polyphenolic polymer (average M.W. = 2100 Da), was tested in cotton rats (Sigmoden hispidus) for antiviral activity against respiratory syncytial (RSV) and parainfluenza type 3 (PIV3) viruses, and for acute toxicity. Significant reductions in pulmonary RSV titers, compared to pulmonary RSV titers in comparably treated control animals, were seen in cotton rats given 1-10 mg SP-303/kg/day intraperitoneally (i.p.) on days 1 through to 3, after experimental inoculation with RSV. The minimum efficacious dose of SP-303 against PIV3, when given i.p. for 3 days, was 3 mg/kg/day. Higher doses of SP-303 could not be given i.p., as doses > or = 30 mg/kg/day given once daily by this route for 3 or more consecutive days caused both significant weight loss and death in infected or uninfected animals. Although no toxicity was observed following oral administration of up to 270 mg of SP-303 daily for 3 days, this compound had variable antiviral activity when given by this route.
Assuntos
Antivirais/uso terapêutico , Biopolímeros/farmacologia , Catequina/análogos & derivados , Vírus da Parainfluenza 3 Humana/efeitos dos fármacos , Infecções por Paramyxoviridae/prevenção & controle , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Infecções por Respirovirus/prevenção & controle , Animais , Antivirais/administração & dosagem , Peso Corporal , Catequina/farmacologia , Técnicas de Cultura , Pulmão/microbiologia , Pulmão/patologia , Infecções por Paramyxoviridae/microbiologia , Plantas Medicinais/química , Infecções por Respirovirus/microbiologia , Ribavirina/farmacologia , Sigmodontinae , Ensaio de Placa ViralRESUMO
Table III summarizes clinical applications of antiviral agents in respiratory viral infections. (table: see text) For influenza A virus infections, both oral amantadine and rimantadine are effective when used for seasonal prophylaxis and for prophylaxis in institutional populations. Both of these drugs, as well as aerosolized ribavirin, have antiviral and therapeutic effects in uncomplicated influenza. It remains to be determined whether any of these modalities or possibly their combined use [44] will be useful in treating severe influenza hospitalized patients or whether they can prevent the development of complications in high risk patients. Unfortunately, there is no parenteral formulation of amantadine or rimantadine for use in critically ill patients. Aerosolized ribavirin has also been shown to have modest therapeutic effects in influenza B virus infection. However, a major need exists for an antiviral which is active against influenza B virus and which can be used on an outpatient basis. Controlled clinical trials have shown that aerosolized ribavirin therapy improves arterial oxygenation and modifies the severity of respiratory syncytial virus bronchiolitis and pneumonia [3,5]. Its role in treating life-threatening disease or in modifying the long-term sequelae of RSV infections are unknown at the present time. Again, a specific antiviral agent is needed for outpatient use in preventing or treating RSV infections. Finally, after over a decade of work since the original observation that intranasal interferon could prevent experimental rhinovirus infection [11], recent studies have established that intranasal rIFN-a2 is effective in the postexposure prophylaxis of rhinovirus colds in families [42]. This strategy needs to be studied with regard to the prevention of infection and its complications in high risk patients and it remains to be determined whether intranasal interferon will have therapeutic activity in established colds.
Assuntos
Antivirais/uso terapêutico , Interferons/uso terapêutico , Infecções por Picornaviridae/tratamento farmacológico , Infecções Respiratórias/tratamento farmacológico , Infecções por Respirovirus/tratamento farmacológico , Viroses/tratamento farmacológico , Adulto , Amantadina/efeitos adversos , Amantadina/metabolismo , Amantadina/uso terapêutico , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Humanos , Vírus da Influenza A , Vírus da Influenza B , Influenza Humana/tratamento farmacológico , Influenza Humana/microbiologia , Influenza Humana/prevenção & controle , Influenza Humana/terapia , Interferons/efeitos adversos , Pessoa de Meia-Idade , Infecções por Picornaviridae/microbiologia , Infecções por Picornaviridae/prevenção & controle , Infecções por Picornaviridae/terapia , Infecções Respiratórias/prevenção & controle , Infecções Respiratórias/terapia , Infecções por Respirovirus/microbiologia , Infecções por Respirovirus/prevenção & controle , Infecções por Respirovirus/terapia , Rhinovirus , Ribavirina/efeitos adversos , Ribavirina/uso terapêutico , Rimantadina/efeitos adversos , Rimantadina/metabolismo , Rimantadina/uso terapêutico , Viroses/prevenção & controle , Viroses/terapiaRESUMO
OBJECTIVE: To define the extent of shedding of respiratory viruses and Mycoplasma pneumoniae among a population of pediatric patients admitted to the hospital during a winter epidemic period and to identify nosocomial infections within this population. DESIGN: An open, prospective survey of patients admitted to three wards (General Medical, Respiratory Infectious, and Infectious Diseases) of a pediatric hospital during a defined three-month period. PATIENTS: All patients with medical, respiratory, and infectious conditions admitted to three wards of the Adelaide Children's Hospital had nasopharyngeal aspirations performed at the time of admission with the purpose of documenting viral and M pneumoniae shedding. Patients were monitored daily for the development of symptoms of respiratory infection or new symptoms of respiratory disease. Such patients underwent a further nasopharyngeal aspiration for the purpose of diagnosing hospital-acquired infection. RESULTS: Nasopharyngeal aspirations were obtained from 601 patients. Forty-seven percent of asymptomatic patients were positive for a respiratory virus or M pneumoniae, and 61% of patients with respiratory symptoms were also positive. Gastroenteritis patients shed viruses in 66% of cases. Respiratory symptoms were initially overlooked by admitting physicians but subsequently identified in 110 cases, and 46% of these were found to be positive for a respiratory virus or M pneumoniae. There were 18 possible hospital acquired infections among the 293 initially virus-negative patients. Multiple isolates were obtained from a substantial number of patients, especially those with respiratory symptoms. CONCLUSIONS: A substantial proportion of all patients admitted to a pediatric hospital during winter represent a potential source of infection, and strict infection control measures should be enacted to limit the spread of these infections.
Assuntos
Infecção Hospitalar/microbiologia , Hospitais Pediátricos , Vírus Sinciciais Respiratórios , Infecções Respiratórias/microbiologia , Infecções por Respirovirus/microbiologia , Austrália/epidemiologia , Criança , Pré-Escolar , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Feminino , Humanos , Lactente , Masculino , Prevalência , Estudos Prospectivos , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/prevenção & controle , Infecções por Respirovirus/epidemiologia , Infecções por Respirovirus/prevenção & controleRESUMO
This study compared the results of a commercially available, direct fluorescent antibody (DFA) test with viral culture in 880 specimens obtained from 690 patients by means of nasopharyngeal swabs. The two tests were congruent in 92.5% (814) of the specimens. The sensitivity of the DFA was 0.95, the specificity was 0.91, the positive predictive value was 0.82, and the negative predictive value was 0.98. Among 548 inpatients, there were 3 mixed infections (RSV and another virus), 8 RSV infections not identified by the DFA, and 35 positive DFA results not confirmed by cell culture. Use of the DFA test alone would have resulted in 502 (92%) correct patient-placement decisions. We conclude that the DFA test provides reliable evidence on which to base patient-placement decisions but that the error rate is too high to permit safe cohorting of high-risk patients, such as those with bronchopulmonary dysplasia.
Assuntos
Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções por Respirovirus/microbiologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Imunofluorescência , Humanos , Lactente , Recém-Nascido , Tempo de Internação , Minnesota , Valor Preditivo dos Testes , Infecções por Respirovirus/epidemiologiaRESUMO
Viral pneumonias are common in infants and young children but rare in adults. Respiratory syncytial virus (RSV) and para-influenza viruses are the most frequent viral pathogens in infants and children. Influenza virus types A and B account for over one half of viral pneumonias in adults. Immunocompromised hosts are susceptible to pneumonias caused by cytomegalovirus (CMV) and other herpesviruses, as well as rubeola and adenovirus. Diagnosis of viral pneumonia depends on appropriate viral cultures and acute and convalescent sera for specific antibodies. Superinfection with bacteria is common in adults. Anti-viral therapy is available for several respiratory viruses. Ribavirin, amantadine/rimantadine, interferon alpha, and acyclovir are antiviral drugs that may be of benefit in treatment and prophylaxis. Prevention of viral pneumonia will depend upon improved viral immunization practices.
Assuntos
Antivirais/uso terapêutico , Pneumonia Viral/microbiologia , Infecções por Adenovirus Humanos/diagnóstico , Infecções por Adenovirus Humanos/tratamento farmacológico , Infecções por Adenovirus Humanos/microbiologia , Adulto , Criança , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/microbiologia , Herpes Simples/diagnóstico , Herpes Simples/tratamento farmacológico , Herpes Simples/microbiologia , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/tratamento farmacológico , Infecções por Herpesviridae/microbiologia , Herpesvirus Humano 3 , Humanos , Influenza Humana/diagnóstico , Influenza Humana/tratamento farmacológico , Influenza Humana/microbiologia , Sarampo/complicações , Infecções por Paramyxoviridae/diagnóstico , Infecções por Paramyxoviridae/tratamento farmacológico , Infecções por Paramyxoviridae/microbiologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/tratamento farmacológico , Vírus Sinciciais Respiratórios , Infecções por Respirovirus/diagnóstico , Infecções por Respirovirus/tratamento farmacológico , Infecções por Respirovirus/microbiologiaRESUMO
Sera from 353 people resident in Dakar, Senegal, West Africa, were tested for hemagglutination-inhibiting antibodies against the avian paramyxovirus Yucaipa. Antibodies were demonstrated in five sera (1.4%), providing new evidence that this virus may infect humans.
Assuntos
Infecções por Respirovirus/microbiologia , Adolescente , Adulto , Animais , Anticorpos Antivirais/imunologia , Criança , Feminino , Cobaias , Testes de Inibição da Hemaglutinação , Humanos , Masculino , Paramyxoviridae , Infecções por Respirovirus/sangue , SenegalRESUMO
A retrospective study of 6 years (1981-1987) experience with clinical specimens of pediatric patients submitted for identification of respiratory viruses was undertaken to determine the prevalence of multiple viral isolates and to assess the impact of dual infections on severity of clinical disease. Respiratory Syncytial Virus (RSV), the most frequently identified agent, was detected in cell culture and/or by immunofluorescence (IF) in 666 of 2,415 specimens examined. A second virus was isolated in cell cultures from 51 of the 666 specimens (7.6%). Cytomegalovirus, rhinoviruses, adenoviruses, influenza and parainfluenza viruses, echoviruses, vaccine strain polio viruses, and herpes simplex virus were identified with RSV. The diagnosis of a dual viral infection would have been missed in 37 of 51 instances (79%) had rapid diagnosis for RSV been employed without inoculation of cell cultures. Demographics and clinical presentations were similar in patients with dual infections or RSV alone. A case-control study comparing patients with dual isolates and patients with RSV alone to determine the effect of multiple viral infections on severity of disease revealed no significant difference. The combined use of rapid methods and isolation in culture provides more complete viral diagnosis and could have an impact on the choice of antiviral agents and the institution of appropriate infection control measures.
Assuntos
Nasofaringe/microbiologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Feminino , Humanos , Lactente , Masculino , Oklahoma , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/microbiologia , Infecções por Respirovirus/complicações , Infecções por Respirovirus/epidemiologia , Infecções por Respirovirus/microbiologia , Estudos Retrospectivos , Virologia/métodos , Viroses/complicações , Viroses/epidemiologia , Viroses/microbiologiaRESUMO
A rapid microplaque technique was developed for the detection of infectious respiratory syncytial virus (RSV) in the lungs of infected mice. Infected lung homogenates were titrated on microwell HEp-2 monolayers and incubated for 24 or 48 h. The microwells were then fixed with 4% formaldehyde in saline, or methanol containing 0.5% hydrogen peroxide. 24-h single cell infectious foci and 48-h microplaques were detected by an indirect immunoperoxidase (IIP) assay using monoclonal antibodies specific for RSV envelope glycoproteins as the first layer. This method can be used for the quantification of lung RSV in large numbers of samples much more rapidly and economically than conventional plaque assay techniques. In addition, the use of the IIP assay renders the system specific for RSV.
Assuntos
Técnicas Imunoenzimáticas , Pulmão/microbiologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções por Respirovirus/microbiologia , Animais , Anticorpos Monoclonais , Camundongos , Camundongos Endogâmicos BALB C , Ensaio de Placa ViralRESUMO
Respiratory syncytial virus (RSV) is the most important cause of bronchiolitis and pneumonia in young children. The development of an animal model of RSV disease serves to better understanding the pathophysiology of airway disease from RSV infection in infants and children. Groups of six lambs were inoculated intratracheally (IT) or intranasally (IN) with a human strain of RSV (H-RSV). For controls 8 lambs received IT virus-free cell lysate. Tachypnea and fever were observed significantly more often following IT than following IN inoculation of H-RSV or IT placebo (for tachypnea: 20 of 69 days, 5 of 63 days, and 3 of 89 days, respectively, P < 0.001; for fever: 6 of 69 days, 0 of 63 days, and 1 of 89 days, respectively, P < 0.02). Nasal fluid production was significantly more frequent in both IT (14 of 69 days) and IN (15 of 63 days) groups than in the placebo group (2 of 87 days, P < 0.001). Postvaccination geometric mean titers (GMT, arithmetic transformation of log 2) of RSV-specific neutralizing antibody were significantly increased in the IT H-RSV group compared with postplacebo GMTs at 1 week (72 vs. 6.7, P < 0.03). By the second week postinoculation both H-RSV-infected groups had comparable levels of RSV-specific neutralizing antibody titers and had significantly greater GMTs for the second through to the fourth week than the placebo group (144, 128, and 4.8, respectively P < 0.0008). Bacterial isolates of the upper airway were comparable among the three groups. Histopathology at day 28 postinoculation was unremarkable for the three study groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Vírus Sinciciais Respiratórios , Infecções por Respirovirus/fisiopatologia , Animais , Animais Recém-Nascidos , Feminino , Humanos , Masculino , Modelos Biológicos , Infecções por Respirovirus/complicações , Infecções por Respirovirus/microbiologia , OvinosRESUMO
Pulmonary complications are a frequent cause of morbidity and mortality following bone marrow transplantation. We examined the results of flexible bronchoscopy (FB) and bronchoalveolar lavage (BAL) in 27 pediatric bone marrow transplant (BMT) recipients with 29 episodes of pulmonary complications. Bone marrow transplant was performed for a variety of malignancies and hematologic disorders. Median age of BMT was 10.3 years (range, 1.7-17.6 years). Median time of FB following BMT was 60 days (range, 11-1,026 days). Routine cytologic and culture techniques were utilized to detect malignant cells, viruses, fungi, bacteria, and protozoa. Positive results were found in 15 (52%) with cytomegalovirus (CMV), the most common positive finding. In 14 (48%) episodes the results were negative. Fourteen patients had follow-up autopsy or open lung biopsy (OLB). Based on autopsy/OLB results, there were two false negatives and no false positives, giving a diagnostic sensitivity of 75% and specificity of 100%. There was one possible complication of FB and BAL. Survival of both positive and negative patients was poor, only seven patients being alive 90 days post-FB with BAL. We conclude that FB with BAL is a safe and accurate procedure for the diagnosis of pulmonary complications of BMT.
Assuntos
Aspergilose/diagnóstico , Transplante de Medula Óssea/efeitos adversos , Brônquios/microbiologia , Líquido da Lavagem Broncoalveolar/microbiologia , Infecções por Citomegalovirus/diagnóstico , Doenças Hematológicas/terapia , Pneumopatias Fúngicas/diagnóstico , Pneumonia Viral/diagnóstico , Vírus Sinciciais Respiratórios/isolamento & purificação , Infecções por Respirovirus/diagnóstico , Adolescente , Aspergilose/etiologia , Aspergilose/microbiologia , Aspergilose/patologia , Transplante de Medula Óssea/métodos , Brônquios/patologia , Líquido da Lavagem Broncoalveolar/parasitologia , Broncoscopia , Criança , Pré-Escolar , Infecções por Citomegalovirus/etiologia , Infecções por Citomegalovirus/microbiologia , Infecções por Citomegalovirus/patologia , Feminino , Humanos , Pneumopatias Fúngicas/etiologia , Pneumopatias Fúngicas/microbiologia , Pneumopatias Fúngicas/patologia , Masculino , Pneumonia por Pneumocystis/diagnóstico , Pneumonia por Pneumocystis/etiologia , Pneumonia por Pneumocystis/microbiologia , Pneumonia por Pneumocystis/patologia , Pneumonia Viral/etiologia , Pneumonia Viral/microbiologia , Pneumonia Viral/patologia , Infecções por Respirovirus/etiologia , Infecções por Respirovirus/microbiologia , Infecções por Respirovirus/patologiaRESUMO
Viral immunofluorescence tests were performed with commercial antisera on 1046 specimens of respiratory, conjunctival corneal and dermal origin to compare the diagnostic effectiveness of direct examination by immunofluorescence with culture. The fluorescence assays were found to be highly sensitive for respiratory syncytial and measles virus in nasopharyngeal aspirates from children, but less satisfactory for other respiratory viruses. The test detected 38% of the adenovirus positives from conjunctival specimens and 67% of the combined herpes simplex virus positives from the latter 3 groups. Despite the reduced sensitivity of fluorescence for some viruses, a case is presented for more widespread use of fluorescence in routine microbiology laboratories because of its simplicity, speed and cost-effectiveness compared with culture which is labour-intensive and time consuming.