Carmo Elias Andrade Melles

Serosubtypes and PorA Types of Neisseria meningitidis Serogroup B Isolated in Brazil during 1997-1998: Overview and Implications for Vaccine Development

ABSTRACT Meningococcal disease caused by N. meningitidisserogroup B (MenB) has been endemic in Brazil since 1997. In this study, we determined the prevalence of serosubtypes of MenB isolated in 10 Brazilian states and the Federal District during 1997 and 1998 and investigated the extent of PorA VR sequence variation among the most prevalent serosubtypes to evaluate the possible use of an outer membrane vesicle (OMV)-, PorA-based vaccine to prevent meningococcal disease in Brazil. During this period, a total of 8,932 cases of meningococcal disease were reported. Only 42% (n = 3,751) of the reported cases were laboratory confirmed, and about 60% (n = 2,255) of those were identified as MenB. Among 1,297 MenB strains selected for this study, the most prevalent serosubtypes were P1.19,15 (66%), P1.7,1 (11%), and P1.7,16 (4%). PorA VR typing showed that 91% of the P1.19,15 strains analyzed had VR1 and VR2 sequences identical to those of the prototype strain. No sequence variation was detected among the 40 strains representing all isolated MenB P1.7,16 strains in the three southern states, where this serosubtype accounts for 75% of the serosubtypes identified. Similarly, all P1.7,1 strains were identified by PorA typing as P1.7-1,1. Although further improvements in the reporting of cases and collection of strains in Brazil are needed, our data suggest that a trivalent OMV-based vaccine prepared with PorA types P1.19,15, P1.7-1,1, and P1.7,16 may be appropriate to control serogroup B meningococcal disease in most of the Brazilian states.

Listeria monocytogenes in renal transplant recipients

Five cases of Listeria monocytogenes bacteremia were observed from April to December 1985, among renal transplant recipients from the same hospital in São Paulo, Brazil. The patients were adults (mean age: 40.6 years), and the basic complaint was fever, with no report of meningeal syndrome. Laboratory tests revealed the presence of two serovars, (1/2)a and 4b, which were classified into three lysotypes. The four strains of serovar 4b showed the same antibiotype, with resistance to cefoxitin, clindamycin, oxacillin and penicillin.

Meningococcal Disease Caused by Neisseria meningitidis Serogroup B Serotype 4 in São Paulo, Brazil, 1990 to 1996

A large epidemic of serogroup B meningococcal disease (MD), has been occurring in greater São Paulo, Brazil, since 1988. A Cuban-produced vaccine, based on outer-membrane-protein (OMP) from serogroup B: serotype 4: serosubtype P1.15 (B:4:P1.15) Neisseria meningitidis, was given to about 2.4 million children aged from 3 months to 6 years during 1989 and 1990. The administration of vaccine had little or no measurable effects on this outbreak. In order to detect clonal changes that could explain the continued increase in the incidence of disease after the vaccination, we serotyped isolates recovered between 1990 and 1996 from 834 patients with systemic disease. Strains B:4:P1.15, which was detected in the area as early as 1977, has been the most prevalent phenotype since 1988. These strains are still prevalent in the area and were responsible for about 68% of 834 serogroup B cases in the last 7 years. We analyzed 438 (52%) of these strains by restriction fragment length polymorphism (RFLPs) of rRNA genes (ribotyping). The most frequent pattern obtained was referred to as Rb1 (68%). We concluded that the same clone of B:4:P1.15-Rb1 strains was the most prevalent strain and responsible for the continued increase of incidence of serogroup B MD cases in greater São Paulo during the last 7 years in spite of the vaccination trial.

Phenotypical and genotypical characterization of Bordetella pertussis strains isolated in São Paulo, Brazil, 1988-2002

Whooping cough or pertussis was a major cause of childhood morbidity and mortality in the world until the introduction of a whole-cell vaccine in the 1940s. However, since the early 1980s whooping cough cases have increased in many countries, becoming an important problem of public health. This increase may be due to accuracy of laboratory diagnosis and reporting of the disease, a decline in immunity over time, demographic changes, and adaptation of the bacterial population to vaccine-induced immunity. The purpose of this study was to analyze phenotypically and genotypically a collection of 67 Bordetella pertussis isolates recovered during the period 1988-2002 in São Paulo State, Brazil to determine their characteristics and relatedness. All isolates were submitted to susceptibility testing to erythromycin, serotyping, and 56 isolates were analyzed by Pulsed Field Gel Electrophoresis (PFGE). All isolates were susceptible to erythromycin and the majority of them belonged to serotype 1,3. The 56 isolates were classified into 11 PFGE profiles according to the differences in banding patterns. Although more than 60% of the isolates were recovered from patients aged less than three months, almost 15% of them were isolated from adolescents/adults evidencing the increase in the incidence of pertussis among this age group.

Aerobic bacteria, Chlamydia trachomatis, Pneumocystis carinii and Cytomegalovirus as agents of severe peneumonia in small infants

The authors studied 58 infants hospitalized for pneumonia in a semi-intensive care unit. Age ranged from 1 complete to 6 incomplete months. The infants were sent from another hospital in 20 cases and from home in a further 38. Pulmonary involvement, which was alveolar in 46 cases and interstitial in 12, was bilateral in 31 children. The investigation was carried out prospectively on the etiological agents associated with respiratory infection to look for evidence of aerobic bacteria (blood cultures), Chlamydia trachomatis and Cytomegalovirus (serology), and Pneumocystis carinii (direct microscopy of tracheal aspirated material). The following infectious agents were diagnosed in 21 children (36.2%): Aerobic bacteria (8), Chlamydia trachomatis (5), Pneumocystis carinii (3), Cytomegalovirus (3), Cytomegalovirus and Chlamydia trachomatis (1), Aerobic bacteria and Cytomegalovirus (1). Seven cases of infection by Chlamydia trachomatis and/or Cytomegalovirus were diagnosed out of the 12 cases with pulmonary interstitial involvement.

Sorotipos de Streptococcus pneumoniae isolados de líquido cefalorraquidiano no período de 1977-1988 na cidade de São Paulo, Brasil

Since 1977, the Instituto Adolfo Lutz (IAL) is having interest in the serotyping of S. pneumoniae or pneumococcus from infections caused by this bacteria. The isolated strains have been sent to the WHO Pneumococcal Reference Center, Pennsylvania, U.S.A.. From 1977 to 1988, 1.000 pneumococcus strains isolated from cerebrospinal fluid were typed, according to Danish nomenclature, and 60 serotypes were identified. The most frequent serotypes were 1, 6B, 18C, 14, 5, 3, 6A, 23F, 19F, and 38. Among different age groups, they showed a variable incidence, with serotype 6B in the ages of zero to almost 2 years old, serotype 1 in the age group of 2 to 50 years old, and serotype 3 in the ages over 50. During the 12 years study, 25 serotypes showed some uniformity in the frequency, the same as with the seasonal fluctuations. Concerning the severity of the pneumococcal infections, chiefly meningitis, and the few information related to pneumococcus serotypes which occur in the area, it was considered of high relevance to have the information of serotypes, once polysaccharide vaccines have been employed with success to prevent these infections.Desde 1977, o Instituto Adolfo Lutz (IAL) vem promovendo a sorotipagem do S. pneumoniae ou pneumococo de infeccoes causadas por esta bacteria. As cepas isoladas tem sido encaminhadas ao WHO Pneumococcal Reference Center, Pensilvania, E.U.A.. De 1977 a 1988, 1.000 cepas de pneumococo isoladas de LCR foram sorotipadas, de acordo com a nomenclatura dinamarquesa, e 60 sorotipos foram identificados. A maior frequencia foi do sorotipo 1, secundado por 6B, 18C, 14, 5, 3, 6A, 23F, 19F e 38. Estes sorotipos distribuidos segundo faixas etarias demonstraram incidencia variavel, notando-se uma certa peculiaridade, ou seja, a predominância do sorotipo 6B na faixa de zero a menos de dois anos; do sorotipo 1 na faixa de 2 ate 50 anos e do sorotipo 3 no grupo acima de 50 anos. Nos 12 anos considerados, 25 sorotipos apresentaram uma certa uniformidade na frequencia e o mesmo foi observado com relacao as estacoes climaticas, apenas com um numero maior de infeccoes meningeas nos meses mais frios. Considerando a gravidade das infeccoes pneumococicas notadamente as meningites, e a pouca informacao relativa aos sorotipos pneumococicos que ocorrem na regiao, julgamos importante essa informacao relativa aos sorotipos, uma vez que tem sido usadas, com sucesso, vacinas polissacaridicas na prevencao dessas infeccoes.

Genetic structure of Neisseria meningitidis serogroup C epidemic strains in South Brazil

In the present study we report the results of an analysis, based on serotyping, multilocus enzyme electrophoresis (MEE), and ribotyping of N. meningitidis serogroup C strains isolated from patients with meningococcal disease (MD) in Rio Grande do Sul (RS) and Santa Catarina (SC) States, Brazil, as the Center of Epidemiology Control of Ministry of Health detected an increasing of MD cases due to this serogroup in the last two years (1992-1993). We have demonstrated that the MD due to N.meningitidis serogroup C strains in RS and SC States occurring in the last 4 years were caused mainly by one clone of strains (ET 40), with isolates indistinguishable by serogroup, serotype, subtype and even by ribotyping. One small number of cases that were not due to an ET 40 strains, represent closely related clones that probably are new lineages generated from the ET 40 clone referred as ET 11A complex. We have also analyzed N.meningitidis serogroup C strains isolated in the greater São Paulo in 1976 as representative of the first post epidemic year in that region. The ribotyping method, as well as MEE, could provide useful information about the clonal characteristics of those isolates and also of strains isolated in south Brazil. The strains from 1976 have more similarity with the actual endemic than epidemic strains, by the ribotyping, sulfonamide sensitivity, and MEE results. In conclusion, serotyping with monoclonal antibodies (C:2b:P1.3), MEE (ET 11 and ET 11A complex), and ribotyping by using ClaI restriction enzyme (Rb2), were useful to characterize these epidemic strains of N.meningitidis related to the increased incidence of MD in different States of south Brazil. It is mostly probable that these N.meningitidis serogroup C strains have poor or no genetic correlation with 1971-1975 epidemic serogroup C strains. The genetic similarity of members of the ET 11 and ET 11A complex were confirmed by the ribotyping method by using three restriction endonucleases.

[Serotypes of Streptococcus pneumoniae isolated from cerebrospinal fluid in 1977-1988 in São Paulo City, Brazil].

Since 1977, the Instituto Adolfo Lutz (IAL) is having interest in the serotyping of S. pneumoniae or pneumococcus from infections caused by this bacteria. The isolated strains have been sent to the WHO Pneumococcal Reference Center, Pennsylvania, U.S.A.. From 1977 to 1988, 1.000 pneumococcus strains isolated from cerebrospinal fluid were typed, according to Danish nomenclature, and 60 serotypes were identified. The most frequent serotypes were 1, 6B, 18C, 14, 5, 3, 6A, 23F, 19F, and 38. Among different age groups, they showed a variable incidence, with serotype 6B in the ages of zero to almost 2 years old, serotype 1 in the age group of 2 to 50 years old, and serotype 3 in the ages over 50. During the 12 years study, 25 serotypes showed some uniformity in the frequency, the same as with the seasonal fluctuations. Concerning the severity of the pneumococcal infections, chiefly meningitis, and the few information related to pneumococcus serotypes which occur in the area, it was considered of high relevance to have the information of serotypes, once polysaccharide vaccines have been employed with success to prevent these infections.Desde 1977, o Instituto Adolfo Lutz (IAL) vem promovendo a sorotipagem do S. pneumoniae ou pneumococo de infeccoes causadas por esta bacteria. As cepas isoladas tem sido encaminhadas ao WHO Pneumococcal Reference Center, Pensilvania, E.U.A.. De 1977 a 1988, 1.000 cepas de pneumococo isoladas de LCR foram sorotipadas, de acordo com a nomenclatura dinamarquesa, e 60 sorotipos foram identificados. A maior frequencia foi do sorotipo 1, secundado por 6B, 18C, 14, 5, 3, 6A, 23F, 19F e 38. Estes sorotipos distribuidos segundo faixas etarias demonstraram incidencia variavel, notando-se uma certa peculiaridade, ou seja, a predominância do sorotipo 6B na faixa de zero a menos de dois anos; do sorotipo 1 na faixa de 2 ate 50 anos e do sorotipo 3 no grupo acima de 50 anos. Nos 12 anos considerados, 25 sorotipos apresentaram uma certa uniformidade na frequencia e o mesmo foi observado com relacao as estacoes climaticas, apenas com um numero maior de infeccoes meningeas nos meses mais frios. Considerando a gravidade das infeccoes pneumococicas notadamente as meningites, e a pouca informacao relativa aos sorotipos pneumococicos que ocorrem na regiao, julgamos importante essa informacao relativa aos sorotipos, uma vez que tem sido usadas, com sucesso, vacinas polissacaridicas na prevencao dessas infeccoes.

Febre purpúrica brasileira: resultados preliminares da investigação etiológica

In the hinterland of the Sao Paulo State, Brazil, a so far non observed disease has been reported from 1984 to 1986. The disease had the clinical characteristics of meningococcemia and the syndrome was named Brazilian Purpuric Fever. In fifteen patients Haemophilus aegyptius was isolated from blood cultures, spinal fluid and conjunctival and oropharyngeal secretions. This paper analyses the importance of such findings in relation to one single previous report of a systemic infection caused by such bacteria.

The use of oligonucleotide probes for meningococcal serotype characterization

In the present study we examine the potential use of oligonucleotide probes to characterize Neisseria meningitidis serotypes without the use of monoclonal antibodies (MAbs). Antigenic diversity on PorB protein forms the bases of serotyping method. However, the current panel of MAbs underestimated, by at least 50% the PorB variability, presumably because reagents for several PorB variable regions (VRs) are lacking, or because a number of VR variants are not recognized by serotype-defining MAbs. We analyzed the use of oligonucleotide probes to characterize serotype 10 and serotype 19 of N. meningitidis. The porB gene sequence for the prototype strain of serotype 10 was determined, aligned with 7 other porB sequences from different serotypes, and analysis of individual VRs were performed. The results of DNA probes 21U (VR1-A) and 615U (VR3-B) used against 72 N. meningitidis strains confirm that VR1 type A and VR3 type B encode epitopes for serotype-defined MAbs 19 and 10, respectively. The use of probes for characterizing serotypes possible can type 100% of the PorB VR diversity. It is a simple and rapid method specially useful for analysis of large number of samples.