Changes in serotype distribution of Haemophilus influenzae meningitis isolates identified through laboratory-based surveillance following routine childhood vaccination against H. influenzae type b in Brazil.

Following routine childhood vaccination against Haemophilus influenzae type b (Hib) disease in Brazil in 1999, passive laboratory surveillance reported increasing numbers of non-b serotypes and nontypeable H. influenzae (NTHi) from meningitis cases. To characterize this increase, we analyzed data on 3910 H. influenzae isolated from cerebrospinal fluid or blood from meningitis cases that were sent to the national reference laboratory for serotyping from 1990 to 2008. Hib accounted for 98% of H. influenzae meningitis isolates received during 1990-1999 versus 59% during 2000-2008, while non-b serotypes increased from 1% to 19% and NTHi increased from 2% to 22% of H. influenzae isolates received during the two periods. Higher proportions of non-b serotypes and NTHi than Hib were isolated from blood rather than cerebrospinal fluid. Estimated incidence rates for H. influenzae meningitis for Sao Paulo state remained below 1 case per million population during 2000-2008, although annual incidence of NTHi meningitis (mean, 0.03 cases per 100,000 population) increased in several age groups. Changes in surveillance for H. influenzae following introduction of Hib conjugate vaccine likely contributed to increased numbers of non-b and nontypeable H. influenzae meningitis isolates received at the national reference laboratory.

Selection of family 1 PspA molecules capable of inducing broad-ranging cross-reactivity by complement deposition and opsonophagocytosis by murine peritoneal cells.

PspA is one of the most well studied pneumococcal proteins and a promising candidate for a future protein-based anti-pneumococcal vaccine. Nevertheless, its structural and serological variability suggests the inclusion of more than one PspA molecule in order to broaden protection. Since different PspAs exhibit variable levels of cross-reactivity, the selection of the protein combination with the highest coverage potential is an essential step for PspA-based vaccine development. This work investigated the level of cross-reactivity within family 1 PspAs, and established a complement based antibody mediated opsonophagocytic assay for measuring the level of cross-protection. Among a panel of ten family 1 PspA molecules, two of them, one belonging to clade 1 and another from clade 2, induced antibodies capable of enhancing complement deposition and mediating the phagocytic killing by mouse peritoneal macrophages of all pneumococci bearing PspA family 1 strains tested, regardless of their serotype. Therefore, we suggest the inclusion of either one in a PspA-based vaccine, as a representative of family 1. Furthermore, our results suggest that opsonophagocytosis by mouse peritoneal cells can be an efficient means of evaluating the induction of protective immune responses in mice across a large number of strains.

Selection of family 1 PspA molecules capable of inducing broad-ranging cross-reactivity by complement deposition and opsonophagocytosis by murine peritoneal cells

PspA is one of the most well studied pneumococcal proteins and a promising candidate for a future protein-based anti-pneumococcal vaccine. Nevertheless, its structural and serological variability suggests the inclusion of more than one PspA molecule in order to broaden protection. Since different PspAs exhibit variable levels of cross-reactivity, the selection of the protein combination with the highest coverage potential is an essential step for PspA-based vaccine development. This work investigated the level of cross-reactivity within family 1 PspAs, and established a complement based antibody mediated opsonophagocytic assay for measuring the level of cross-protection. Among a panel of ten family 1 PspA molecules, two of them, one belonging to clade 1 and another from clade 2, induced antibodies capable of enhancing complement deposition and mediating the phagocytic killing by mouse peritoneal macrophages of all pneumococci bearing PspA family 1 strains tested, regardless of their serotype. Therefore, we suggest the inclusion of either one in a PspA-based vaccine, as a representative of family 1. Furthermore, our results suggest that opsonophagocytosis by mouse peritoneal cells can be an efficient means of evaluating the induction of protective immune responses in mice across a large number of strains.

An unusual presentation of leprosy at diagnosis: erythema multiforme-like type 2 reaction

Este estudo descreve um caso de Eritema Multiforme (EM) como a primeira manifestação clínica de Hanseníase (MH) em uma mulher de 35 anos. Quando atendida em um Hospital, a paciente apresentava febre, artralgia, e placas eritematosas em ambos os cotovelos e joelhos bilateralmente, algumas com bolhas e/ou necrose central. O diagnóstico foi confirmado por meio de biópsias de pele, que revelaram um padrão histopatológico compatível com EM, além da presença decélulas de Virchow e bacilos álcool-ácido resistentes (BAAR). Médicos em geral, especialmente os clínicos, devem considerar MH como diagnóstico diferencial de EM, especialmente em regiões endêmicas da doença.

This study describes a case of erythema multiforme (EM) as the first clinical manifestation of leprosy in a 35-year-old woman. She presented at the hospital with fever, arthralgia and erythematous plaques on both elbows and knees, some of them with bullous or necrotic center areas. The diagnosiswas confirmed by skin biopsy, which revealed a well-known EM pattern, and also showed the presence of Virchow cells and acid-fast bacilli. Physicians should be aware that leprosy must beconsidered in the differential diagnosis of EM, especially in endemic regions.

Immunization of mice with single PspA fragments induces antibodies capable of mediating complement deposition on different pneumococcal strains and cross-protection.

PspA is an important candidate for a vaccine with serotype-independent immunity against pneumococcal infections. Based on sequence relatedness, PspA has been classified into three families comprising six clades. We have previously addressed the cross-reactivity of antibodies against PspA fragments containing the N-terminal and proline-rich regions of PspA from clades 1 to 5 (PspA1, PspA2, PspA3, PspA4, and PspA5) by Western blot analysis and reported that anti-PspA4 and anti-PspA5 were able to recognize pneumococci expressing PspA proteins from all of the clades analyzed. We have now analyzed the functional capacity of these antibodies to bind and to mediate complement deposition on intact bacteria in vitro. Our results show that both PspA4 and PspA5 elicit antibodies that are able to bind and to mediate complement deposition efficiently on pneumococcal strains bearing PspA proteins from clades 1 to 5. Moreover, mice immunized with PspA4 and PspA5 were protected against an intranasal lethal challenge with strains expressing PspA proteins from the two major families. PspA4 and PspA5 are thus able to induce antibodies with a high degree of cross-reactivity in vitro, which is reflected in cross-protection of mice. We have also analyzed the contribution of the nonproline (NonPro) block within the conserved proline-rich region to the reactivity of anti-PspA antibodies, and the results indicate that N-terminal alpha-helical region, the blocks of proline repeats, and the NonPro region can influence the degree of cross-reactivity of antibodies to PspA.

Spatial clusters of violent deaths in a newly urbanized region of Brazil: highlighting the social disparities.

BACKGROUND: Deaths due to homicides and traffic accidents among youth are a public health issue worldwide. Studies of the complex network of cause and effect on this topic point to both poverty and health inequalities. Different investigational approaches to intentional and unintentional deaths combined with socioeconomic variables can help create a better understanding of the association between violence and socioeconomic conditions. This study analyzed the spatial distribution and potential clusters of risk for intentional and unintentional deaths among youths aged 15-24 years in Goiânia, a newly urbanized city in central Brazil. METHODS: Death data and residential addresses were extracted from the national Mortality Information System and validated by household visits. To detect all potential cases, we prospectively investigated every death classified as a transport accident, assault, legal intervention, intentional self-harm, unknown underlying cause, and undetermined intent according to the ICD-10.The Geographical Information System was used to plot residential addresses, and cases were interactively geocoded to the residential address level using a digital map of the municipality. Spatial scan statistic was applied (Poisson model) to identify clusters of census tracts with high mortality due to intentional injuries and traffic accidents. The socioeconomic variables obtained using census data were compared between the most likely cluster and other areas of the municipality. RESULTS: The most violent deaths among young people were due to intentional injuries. Between August 2005 and August 2006, 145 addresses for cases of intentional injuries and traffic accidents were located and geocoded. No significant clusters for deaths due to traffic accidents were found within the municipality. One significant cluster (RR = 4.65; p = 0.029) composed of 14 cases of intentional deaths, mostly homicides, was detected in an emergent, populated, and very poor area on the outskirts of the town. This cluster had a significantly higher proportion of people with the lowest educational status, lowest income, and poor housing conditions in comparison to the remainder of the municipality. CONCLUSION: Our findings highlight the link between social inequalities and intentional deaths, clearly showing the need for urgent social interventions to reduce violence and premature mortality.

Estimating the cost-effectiveness of pneumococcal conjugate vaccination in Brazil / Cálculo de la relación costo-efectividad de la vacuna conjugada antineumocócica en Brasil

OBJECTIVE: To compare the costs and benefits of pneumococcal conjugate vaccination compared with no vaccination from the perspectives of the health care system and society. METHODS: Using data from established sources, we estimated the incidence and mortality due to invasive pneumococcal disease, pneumonia, and acute otitis media (AOM) for a hypothetical birth cohort of children from birth to 5 years. RESULTS: A universal pneumococcal conjugate vaccination program was estimated capable of annually avoiding 1 047 cases of invasive disease, 58 226 cases of pneumonia, and 209 862 cases of AOM. When herd immunity effects were considered, the program prevented 1.3 million cases of pneumococcal disease and over 7 000 pneumococcal deaths. At a vaccination cost of R$ 51.12 (US$ 26.35) per dose, vaccination would cost annually R$ 4 289 (US$ 2,211) per disability-adjusted life years averted. This does not take into account herd immunity effects. CONCLUSIONS: At the current vaccine price, conjugate vaccination could be a cost-effective investment compared to other options to control childhood diseases. Further analysis is required to determine whether vaccination at the current price is affordable to Brazil.

OBJETIVO: Comparar los costos y los beneficios de la aplicación de la vacuna conjugada antineumocócica en comparación con la no vacunación, desde las perspectivas del sistema de salud y la sociedad. MÉTODOS: A partir de fuentes reconocidas, se estimaron la incidencia y la mortalidad por enfermedad neumocócica invasora, neumonía y otitis media aguda (OMA) para una cohorte hipotética de niños desde su nacimiento hasta los 5 años. RESULTADOS: Se estimó que un programa de vacunación universal con una vacuna conjugada antineumocócica sería capaz de evitar anualmente 1 047 casos de la enfermedad invasora, 58 226 casos de neumonía y 209 862 casos de OMA. Si se considera el efecto de la inmunidad de grupo, el programa evitaría 1,3 millones de casos de enfermedad y más de 7 000 muertes por infección neumocócica. A R$ 51,12 (US$ 26,35) por dosis, la vacunación costaría anualmente R$ 4 286 (US$ 2,211) por cada año de vida ajustado por discapacidad evitado, sin tomar en cuenta el efecto de la inmunidad de grupo. CONCLUSIONES: En comparación con otras opciones de control de estas enfermedades infantiles y con los precios actuales de la vacuna conjugada, la vacunación antineumocócica podría ser una inversión efectiva en función del costo. Se requieren más estudios para determinar si la vacunación es costeable para Brasil a los precios actuales.

Estimating the cost-effectiveness of pneumococcal conjugate vaccination in Brazil.

OBJECTIVE: To compare the costs and benefits of pneumococcal conjugate vaccination compared with no vaccination from the perspectives of the health care system and society. METHODS: Using data from established sources, we estimated the incidence and mortality due to invasive pneumococcal disease, pneumonia, and acute otitis media (AOM) for a hypothetical birth cohort of children from birth to 5 years. RESULTS: A universal pneumococcal conjugate vaccination program was estimated capable of annually avoiding 1 047 cases of invasive disease, 58 226 cases of pneumonia, and 209 862 cases of AOM. When herd immunity effects were considered, the program prevented 1.3 million cases of pneumococcal disease and over 7 000 pneumococcal deaths. At a vaccination cost of R$ 51.12 (US$ 26.35) per dose, vaccination would cost annually R$ 4 289 (US$ 2,211) per disability-adjusted life years averted. This does not take into account herd immunity effects. CONCLUSIONS: At the current vaccine price, conjugate vaccination could be a cost-effective investment compared to other options to control childhood diseases. Further analysis is required to determine whether vaccination at the current price is affordable to Brazil.

Recognition of pneumococcal isolates by antisera raised against PspA fragments from different clades.

Pneumococcal surface protein A (PspA) is an important vaccine candidate against pneumococcal infections, capable of inducing protection in different animal models. Based on its structural diversity, it has been suggested that a PspA-based vaccine should contain at least one fragment from each of the two major families (family 1, comprising clades 1 and 2, and family 2, comprising clades 3, 4 and 5) in order to elicit broad protection. This study analysed the recognition of a panel of 35 pneumococcal isolates bearing different PspAs by antisera raised against the N-terminal regions of PspA clades 1 to 5. The antiserum to PspA clade 4 was found to show the broadest cross-reactivity, being able to recognize pneumococcal strains containing PspAs of all clades in both families. The cross-reactivity of antibodies elicited against a PspA hybrid including the N-terminal region of clade 1 fused to a shorter and more divergent fragment (clade-defining region, or CDR) of clade 4 (PspA1-4) was also tested, and revealed a strong recognition of isolates containing clades 1, 4 and 5, and weaker reactions with clades 2 and 3. The analysis of serum reactivity against different PspA regions further revealed that the complete N-terminal region rather than just the CDR should be included in an anti-pneumococcal vaccine. A PspA-based vaccine is thus proposed to be composed of the whole N-terminal region of clades 1 and 4, which could also be expressed as a hybrid protein.

Prevalence and risk factors for nasopharyngeal carriage of Streptococcus pneumoniae among adolescents.

Data on the prevalence of pneumococcal nasopharyngeal carriage and its risk factors among adolescents are scarce. The aim of this study was to provide such information. A cross-sectional, population-based prospective study was conducted. Participants were 1013 adolescents (age range 10-19 years) randomly recruited in 22 public schools. Those schools were randomly chosen among 307 public schools from 11 Sanitary Districts of Salvador, Brazil. Nasopharyngeal samples were assessed by standard procedures to recover and identify Streptococcus pneumoniae. Data on potential risk factors were gathered by confidential interview based on a standardized questionnaire. Pneumococci were recovered from 8.2 % [83/1013, 95 % confidence interval (CI) 6.6-10.0]. By stepwise logistic regression, pneumococcal colonization was independently associated with younger age [odds ratio (OR) 0.85, 95 % CI 0.77-0.94, P=0.001], being male (OR 1.78, 95 % CI 1.11-2.85, P=0.02), exposure to passive smoke in the household (OR 1.76, 95 % CI 1.10-2.79, P=0.02), having an upper respiratory infection during recruitment (OR 2.67, 95 % CI 1.67-4.28, P<0.001) and having a history involving an episode of acute asthma during the last year (OR 2.89, 95 % CI 1.18-7.08, P=0.03). The estimated probability of pneumococcal colonization decreased with age (chi(2) for trend=8.52, P=0.003). These findings provide tools for increasing the use of prevention strategies for pneumococcal diseases, such as pneumococcal vaccination among asthmatic patients and public health measures to stop smoking.

Increase in numbers of beta-lactam-resistant invasive Streptococcus pneumoniae in Brazil and the impact of conjugate vaccine coverage.

A comprehensive investigation of invasive Streptococcus pneumoniae was carried out in Brazil as part of the programme of the national epidemiological surveillance system. The investigation provided data on the trends of resistance to antimicrobial agents. A total of 6470 isolates of S. pneumoniae collected in the country from 1993 to 2004 were tested. During this period of time, the number of penicillin-resistant strains rose from 10.2 to 27.9%. The proportions of intermediate and high-level resistant strains in 1993, which were 9.1 and 1.1%, respectively, rose to 22.0 and 5.9% in 2004. Geometric mean MICs for penicillin increased after the year 2000, to 0.19 microg ml(-1) in 2004; most of these isolates were from patients with pneumonia and from children under 5 years old, and belonged to serotype 14. There was a significant increase in the number of isolates belonging to serotypes included in the 7-valent conjugate vaccine from children under 5 years old: from 48.6% in 1993 to 69.6% in 2004, mainly related to an increase in the frequency of serotype 14 isolates. From 2000 to 2004, meningitis isolates showed higher resistance rates to cefotaxime (2.6%) compared to non-meningitis isolates (0.7%); percentages of isolates resistant to trimethoprim-sulfamethoxazole, tetracycline, erythromycin, chloramphenicol and rifampicin were 65, 14.6, 6.2, 1.3 and 0.7 %, respectively. No levoflaxin resistance was observed. Multidrug resistance was identified in 4.6% of isolates, of which 3.8% were resistant to three classes, 0.7% to four classes and 0.1% to five classes of antimicrobial agent. The study provides valuable information that may support empirical antimicrobial therapy for severe S. pneumoniae infections in Brazil, and emphasizes the need for conjugate pneumococcal vaccination.

Neonatal mortality in intensive care units of Central Brazil.

OBJECTIVE: To identify potential prognostic factors for neonatal mortality among newborns referred to intensive care units. METHODS: A live-birth cohort study was carried out in Goiânia, Central Brazil, from November 1999 to October 2000. Linked birth and infant death certificates were used to ascertain the cohort of live born infants. An additional active surveillance system of neonatal-based mortality was implemented. Exposure variables were collected from birth and death certificates. The outcome was survivors (n=713) and deaths (n=162) in all intensive care units in the study period. Cox's proportional hazards model was applied and a Receiver Operating Characteristic curve was used to compare the performance of statistically significant variables in the multivariable model. Adjusted mortality rates by birth weight and 5-min Apgar score were calculated for each intensive care unit. RESULTS: Low birth weight and 5-min Apgar score remained independently associated to death. Birth weight equal to 2,500 g had 0.71 accuracy (95% CI: 0.65-0.77) for predicting neonatal death (sensitivity =72.2%). A wide variation in the mortality rates was found among intensive care units (9.5-48.1%) and two of them remained with significant high mortality rates even after adjusting for birth weight and 5-min Apgar score. CONCLUSIONS: This study corroborates birth weight as a sensitive screening variable in surveillance programs for neonatal death and also to target intensive care units with high mortality rates for implementing preventive actions and interventions during the delivery period.

Neonatal mortality in intensive care units of Central Brazil

OBJETIVO: Identificar fatores prognósticos de mortalidade neonatal em unidades de cuidados intensivos. MÉTODOS: Realizou-se estudo de coorte de nascidos vivos do município de Goiânia, no período de novembro de 1999 a outubro de 2000. Procedeu-se à vinculação das bases de dados das declarações de nascidos vivos e de óbitos, das quais as variáveis de exposição foram extraídas. Adicionalmente, foi implementado um sistema ativo de vigilância de mortalidade neonatal. A variável de efeito foi constituída dos recém-nascidos admitidos nas unidades de cuidados intensivos que sobreviveram (n=713) e dos que morreram (n=162). Utilizou-se o modelo de regressão de Cox para identificar fatores associados à mortalidade neonatal e a curva Receiver Operating Characteristic para avaliar a acurácia de variáveis estatisticamente significantes em modelo multivariado. Taxas de mortalidade ajustadas por peso de nascimento e Apgar do quinto minuto foram calculadas para cada unidade de cuidados intensivos. RESULTADOS: Baixo peso ao nascer e Apgar do quinto minuto permaneceram associados ao óbito neonatal, de forma independente. Peso ao nascer igual a 2.500 g apresentou acurácia de 0,71 (IC 95 por cento: 0,65-0,77) na predição de óbito neonatal (sensibilidade =72,2 por cento). Observou-se ampla variação nas taxas de mortalidade entre as unidades de cuidados intensivos (9,5 por cento-48,1 por cento) sendo que duas delas permaneceram com taxas significantemente mais altas após o ajuste da mortalidade pelo peso de nascimento e Apgar. CONCLUSÕES: Os resultados mostraram que o peso de nascimento é uma variável sensível para uso em triagens em programas de vigilância de óbito neonatal e pode identificar as unidades de cuidados intensivos com altas taxas de mortalidade para implementação de ações preventivas e para intervenções no período intra-parto.

Short report: benznidazole efficacy among Trypanosoma cruzi-infected adolescents after a six-year follow-up.

Data from a six-year follow-up of Trypanosoma cruzi-infected adolescents enrolled in a randomized, double-blind, clinical trial of benznidazole showed successful chemotherapy in 64.7% (95% confidence interval [CI] = 50.2-78.7) and 84.7% (95% CI = 66.8-92.9), respectively, by intention-to treat and by per protocol analysis measured by seronegativity in a chemiluminescent enzyme-linked immunosorbent assay with a purified trypomastigote mucin antigen. No incident case of cardiomyopathy was detected by electrocardiogram assessment in this cohort of adolescents who had been infected in childhood. The persistent and consistently long-term negative serologic reactions suggest the absence of the parasite in the treated patients and reinforces the recommendation of early benznidazole chemotherapy for T. cruzi-infected infants as a public health policy in endemic areas.

Household survey of dengue infection in central Brazil: spatial point pattern analysis and risk factors assessment.

Urban dengue fever is now considered a major public health threat in most American countries. A household survey was conducted in the city of Goiania in central Brazil in 2001 to assess prevalence of dengue infection and individual and area-based risk factors. Spatial point pattern analysis was performed using the dual Kernel method. A total of 1,610 households were surveyed; 1,585 individuals more than five years old had blood and data collected. Sera were tested for IgM/IgG antibodies by an enzyme-linked immunoassay. Area-based indicators derived from census data were linked to geocoded residential address. The seroprevalence of dengue was 29.5% and the estimate prevalence surface reached 50% in the outskirts areas. The risk of infection was significantly associated with older age (P < 0.01), low education (odds ratio [OR] = 3.45, 95% confidence interval [CI] = 1.82-6.55), and low income (OR = 1.32, 95% CI = 1.02-1.71) in multivariate analysis. This study highlighted the heterogeneity of dengue transmission within the city and can assist in spatial targeting control interventions.

[Impact of Haemophilus influenzae b (Hib) vaccination on meningitis in Central Brazil]. / Impacto da vacinação contra o Haemophilus influenzae b na redução de meningites, Goiás.

OBJECTIVE: To assess the impact of the Haemophilus influenzae b (Hib) conjugate vaccine in reducing the incidence of meningitis among children under five years old. METHODS: A 'before-after' design was used to compare Hib meningitis incidence rates in the pre-vaccine (July 1995 - June 1999) and post-vaccine (July 1999 - June 2001) periods in the state of Goias, central Brazil. Bacterial meningitis case definition was based on World Health Organization criteria. Incidence rates of S. pneumoniae and N. meningitidis were used for comparison purposes. Chi-squared and Student's t tests were used for statistical analysis. P-values below 0.05 were considered as statistically significant. RESULTS: 979 children with acute bacterial meningitis were detected throughout the entire period. The incidence rate of Hib meningitis decreased from 10.8 (x10(5)) in the pre-vaccine period to 2.3 (x10(5)) in the 2nd year post vaccination, leading to a risk reduction of 78%, targeted to the 7-23 months age group (p<0.05). A total of 65 cases of Hib meningitis were prevented. An increase in S. pneumoniae meningitis was observed. Vaccine failure was detected in one child. CONCLUSIONS: This study showed that mass immunization with Hib conjugate vaccine brought about an expressive decline in childhood Hib meningitis in Goias soon after the first year. Notwithstanding, an enhancement of surveillance using high-accuracy tools is essential to: (i) detect a possible reemergence of Hib; (ii) identify vaccine failure, and (iii) monitor changes in the H. influenzae serotype profile over time.

Impacto da vacinação contra o Haemophilus influenzae b na redução de meningites, Goiás / Impact of Haemophilus influenzae b (Hib) vaccination on meningitis in Central Brazil

OBJETIVO: Avaliar o impacto da vacinação contra o Haemophilus influenzae b na incidência de meningites em crianças menores de cinco anos de idade. MÉTODOS: Utilizou-se o delineamento tipo "antes-depois" para comparar as taxas de incidência de meningites por Haemophilus influenzae b nos períodos pré-vacinação (julho/95-junho/99) e pós-vacinação (julho/99-junho/2001) no Estado de Goiás. A definição de caso de meningite bacteriana seguiu os critérios da Organização Mundial de Saúde. As taxas de meningite por Streptococcus pneumoniae e Neisseria. meningitidis foram utilizadas para efeito de comparação. Para análise estatística foram utilizados o teste de chi2 e o t de Student. Valores de p<0,05 foram considerados estatisticamente significantes. RESULTADOS: Foi detectada meningite bacteriana aguda em 979 crianças no período de estudo. A incidência de meningite por Haemophilus influenzae b diminuiu de 10,8x10(5) no período pré-vacinal para 2,3x10(5) no segundo ano pós-vacina, significando 78 por cento de redução no risco, principalmente na faixa etária de 7-23 meses (p<0,05). Foram prevenidos 65 casos de meningite por Haemophilus influenzae b. Observou-se aumento na incidência de meningite por S. pneumoniae. Foi observada falha vacinal em um caso. CONCLUSÕES: Expressivo declínio da incidência de meningite por Haemophilus influenzae b foi detectado, precocemente, logo após o primeiro ano de introdução da vacina contra o Haemophilus influenzae b. Assim, se faz necessária a vigilância contínua com instrumental de alta acurácia para: (i) detectar re-emergência do Haemophilus influenzae b; (ii) avaliar possibilidade de falha vacinal; (iii) identificar mudanças no padrão dos sorotipos do H. influenzae.

Typing of pneumococcal surface protein A (PspA) in Streptococcus pneumoniae isolated during epidemiological surveillance in Brazil: towards novel pneumococcal protein vaccines.

Pneumococcal protein vaccine based on pneumococcal surface protein A (PspA) is in development with the potential to offer broad range of protection against different strains. We have investigated the frequency of PspA family 1 (Fam1) and family 2 (Fam2) proteins among Streptococcus pneumoniae recovered from ongoing surveillance in Brazil. Fam1 and Fam2 were expressed in comparable rates among 366 isolates, with the potential coverage of 94.3%. PspA families were not associated to age group or source of isolates. However, considering the significant tendency of increasing prevalence of Fam2 associated to widespread dissemination of the genetically-related resistant strains, the monitoring of the PspA families derived from population-based data may be necessary in the context of vaccine development.

Quantification of Epstein-Barr viral load and determination of a cut-off value to predict the risk of post-transplant lymphoproliferative disease in a renal transplant cohort.

Post-transplant lymphoproliferative disorder (PTLD) is a life-threatening Epstein-Barr virus (EBV)-driven B-cell malignancy occurring in 1 to 3% of renal transplant patients. Recently, EBV DNA quantification has become a useful tool for identifying patients at risk of developing PTLD. However, studies on EBV load differ in design, methodology and type of patients.