IgG Isotypes Targeting a Recombinant Chimeric Protein of Trypanosoma cruzi in Different Clinical Presentations of Chronic Chagas Disease.

Chagas disease (CD) is caused by the protozoan Trypanosoma cruzi, which leads to a spectrum of clinical presentations that range from asymptomatic to severe cardiac involvement. The host immune response plays a pivotal role in disease progression. Ig isotypes may contribute to disease pathogenesis. Investigating these components can provide insights into the immunopathogenic mechanisms underlying CD. This cross-sectional study aims to establish a correlation between the Ig profile of individuals infected with T. cruzi with the clinical forms of chronic CD. Serum samples were collected from partner institutions in different states of Brazil. Individuals diagnosed with chronic CD were categorized based on the clinical form of the disease. The indirect ELISA method using the recombinant chimeric Molecular Biology Institute of Paraná membrane protein 8.4 as the antigen was used to determine the Ig profile, including total IgG, IgG1, IgG2, IgG3, and IgG4. Ninety-seven serum samples from patients classified as negative (NEG, n = 38), indeterminate (IND, n = 24), mild cardiac (MC, n = 20), and severe cardiac (SC, n = 15) forms were analyzed. IgG1 exhibited greater levels compared with the other isotypes, showing a significant difference between the MC and IND groups. IgG3 levels were greater in individuals from the MC group compared with the SC group. IgG1 and IgG3 isotypes can serve as biomarkers to evaluate the progression of CD because they exhibit variations across clinical groups. Additional longitudinal studies are necessary to explore the relationship between antibody kinetics and the development of tissue damage.

Accuracy of the urine point-of-care circulating cathodic antigen assay for diagnosing Schistosomiasis mansoni infection in Brazil: A multicenter study.

BACKGROUND: The World Health Organization recommends a market-ready, urine-based point-of-care diagnostic test for circulating cathodic antigens (CCA) to determine the prevalence of S. mansoni. This study evaluated the performance of the URINE CCA (SCHISTO) ECO TESTE® (POC-ECO), which is currently available in Brazil. METHODS: Residents from eight sites with different prevalence estimates provided one urine sample for POC-ECO and one stool sample for Kato-Katz (KK) and Helmintex® (HTX) testing as an egg-detecting reference for infection status. RESULTS: None of the study sites had significantly higher POC-ECO accuracy than KK. CONCLUSIONS: POC-ECO is not currently recommended in Brazilian schistosomiasis elimination programs.

Accuracy of the urine point-of-care circulating cathodic antigen assay for diagnosing Schistosomiasis mansoni infection in Brazil: A multicenter study

ABSTRACT Background: The World Health Organization recommends a market-ready, urine-based point-of-care diagnostic test for circulating cathodic antigens (CCA) to determine the prevalence of S. mansoni. This study evaluated the performance of the URINE CCA (SCHISTO) ECO TESTE® (POC-ECO), which is currently available in Brazil. Methods: Residents from eight sites with different prevalence estimates provided one urine sample for POC-ECO and one stool sample for Kato-Katz (KK) and Helmintex® (HTX) testing as an egg-detecting reference for infection status. Results: None of the study sites had significantly higher POC-ECO accuracy than KK. Conclusions: POC-ECO is not currently recommended in Brazilian schistosomiasis elimination programs.

Reliability of point-of-care circulating cathodic antigen assay for diagnosing schistosomiasis mansoni in urine samples from an endemic area of Brazil after one year of storage at -20 degrees Celsius.

BACKGROUND: The World Health Organization recommends reliable point-of-care (POC) diagnostic testing to eliminate schistosomiasis. Lateral flow immunoassay that detects schistosome circulating cathodic antigen (CCA) in urine to establish prevalence thresholds for intervention in endemic areas is recommended. Stored urine may be useful if surveying at-risk populations is delayed or interrupted by unforeseen circumstances, such as the current COVID-19 pandemic. This study evaluated the manufacturer's claim that Schistosoma mansoni infection can be reliably diagnosed in urine samples stored at -20°C for one year. METHODS: Two-hundred-forty-two subjects from an endemic site in Brazil provided one urine sample each for testing with URINE CCA (SCHISTO) ECO TESTE® (POC-ECO) and one stool sample each for testing with Kato-Katz (KK) and Helmintex® (HTX) as a robust reference standard for infection status. At least 2 ml of urine from each participant was stored at -20°C; after one year, 76 samples were randomly selected for POC-ECO retesting. RESULTS: The POC-ECO agreement between freshly collected and stored urine was inadequate considering trace results as positive (Cohen's kappa coefficient κ = 0.08) and negative (κ = 0.36). POC-ECO accuracy was not significantly greater than that of routine KK (54%; 95% confidence interval: 42.1%-65.5%). CONCLUSIONS: The precision and accuracy of POC-ECO have to be optimized in both freshly collected and stored urine before it can be recommended for use in control programs in Brazil.

Reliability of point-of-care circulating cathodic antigen assay for diagnosing schistosomiasis mansoni in urine samples from an endemic area of Brazil after one year of storage at -20 degrees Celsius

ABSTRACT Background The World Health Organization recommends reliable point-of-care (POC) diagnostic testing to eliminate schistosomiasis. Lateral flow immunoassay that detects schistosome circulating cathodic antigen (CCA) in urine to establish prevalence thresholds for intervention in endemic areas is recommended. Stored urine may be useful if surveying at-risk populations is delayed or interrupted by unforeseen circumstances, such as the current COVID-19 pandemic. This study evaluated the manufacturer's claim that Schistosoma mansoni infection can be reliably diagnosed in urine samples stored at -20°C for one year. Methods Two-hundred-forty-two subjects from an endemic site in Brazil provided one urine sample each for testing with URINE CCA (SCHISTO) ECO TESTE® (POC-ECO) and one stool sample each for testing with Kato-Katz (KK) and Helmintex® (HTX) as a robust reference standard for infection status. At least 2 ml of urine from each participant was stored at -20°C; after one year, 76 samples were randomly selected for POC-ECO retesting. Results: The POC-ECO agreement between freshly collected and stored urine was inadequate considering trace results as positive (Cohen's kappa coefficient κ = 0.08) and negative (κ = 0.36). POC-ECO accuracy was not significantly greater than that of routine KK (54%; 95% confidence interval: 42.1%-65.5%). Conclusions The precision and accuracy of POC-ECO have to be optimized in both freshly collected and stored urine before it can be recommended for use in control programs in Brazil.

Seroprevalence of Trypanosoma cruzi infection among blood donors in the state of Bahia, Brazil.

INTRODUCTION: Chagas disease (CD) affects 5.7-7.0 million individuals worldwide, and its prevalence reached 25.1% in the state of Bahia, Brazil. There is an association between the prevalence of CD, the socioeconomic status of the population, and the risk of re-emergence due to non-vectorial transmission, such as blood transfusion. This study determined the seroprevalence of T. cruzi infection among blood donors in the state of Bahia, located in northeastern Brazil, and their epidemiological profile during a 10-year period. METHODS: We performed a descriptive cross-sectional study involving a database review. Data were collected from patients with non-negative results for T. cruzi infection during a 10-year period. RESULTS: A total of 3,084 (0.62%) samples were non-negative for T. cruzi infection in an initial serological screening, and 810 (0.16%) samples were non-negative in the second screening. The correlation between infection and age (30 years or older) and between infection and lower educational level (12 years or less) in the first and second screening was statistically significant. The seroprevalence of T. cruzi infection was higher in men in the first screening. In addition, 99.52% of the municipalities of Bahia had at least one case of CD. Livramento de Nossa Senhora and Salvador presented the highest disease prevalence and recurrence, respectively. CONCLUSIONS: The seroprevalence of T. cruzi infection in these populations was lower than that found in other studies in Brazil but was comparatively higher in densely-populated areas. The demographic characteristics of our population agreed with previous studies.

Detection of anti-Trypanosoma cruzi antibodies by chimeric antigens in chronic Chagas disease-individuals from endemic South American countries.

BACKGROUND: Laboratory diagnosis of chronic Chagas disease is a troubling factor due to lack of reference tests. The WHO suggests the use of two distinct commercial serological tests in parallel. The performance of commercial immunoassays might fluctuate depending on the antigenic matrices and the local strains of T. cruzi in different geographical settings. The use of antigenic matrices based on chimeric proteins can solve these limitations. Here, we evaluated the diagnostic performance of two chimeric T. cruzi antigens (IBMP-8.1 and -8.4) to diagnose chronic Chagas disease in individuals from endemic South American countries. METHODOLOGY/PRINCIPAL FINDINGS: IBMP-8.1 and IBMP-8.4 chimeric antigens were expressed as soluble proteins in E. coli and purified using chromatography methods. Reactivity of IBMP-8.1 and IBMP-8.4 was assessed using an in-house ELISA with sera from 122 non-infected and 215 T. cruzi-infected individuals from Argentina, Bolivia, and Paraguay. Cut-off values were based on ROC curves and performance parameters were determined using a dichotomous approach. Area under the curve values were > 99.7% for both IBMP-8.1 and IBMP-8.4 antigens. IgG levels in T. cruzi-positive and negative samples were higher for IBMP-8.4 than IBMP-8.1. Both IBMP-8.1 and -8.4 were 100% specific, while IBMP-8.4 were 100% sensitive compared to IBMP-8.1 (95.3%). Admitting RI values of 1.0 ± 0.10 as the inconclusive interval, 6.2% of the samples tested using IBMP-8.1 and 2.1% using IBMP-8.4 fell inside the grey zone. Based on accuracy and diagnostic odds ratio values, IBMP-8.4 presented the best performance. Differences in sensitivity and IgG levels among the samples from Argentina, Bolivia, and Paraguay were not significant. CONCLUSIONS/SIGNIFICANCE: Our findings showed a notable performance of IBMP-8.1 and -8.4 chimeric antigens in diagnosing chronic Chagas disease in individuals from endemic South American countries, confirming our hypothesis that these antigens could be used in geographical areas where distinct T. cruzi DTUs occur.

Seroprevalence of trypanosoma cruzi infection among blood donors in the state of Bahia, Brazil

Abstract INTRODUCTION: Chagas disease (CD) affects 5.7-7.0 million individuals worldwide, and its prevalence reached 25.1% in the state of Bahia, Brazil. There is an association between the prevalence of CD, the socioeconomic status of the population, and the risk of re-emergence due to non-vectorial transmission, such as blood transfusion. This study determined the seroprevalence of T. cruzi infection among blood donors in the state of Bahia, located in northeastern Brazil, and their epidemiological profile during a 10-year period. METHODS: We performed a descriptive cross-sectional study involving a database review. Data were collected from patients with non-negative results for T. cruzi infection during a 10-year period. RESULTS: A total of 3,084 (0.62%) samples were non-negative for T. cruzi infection in an initial serological screening, and 810 (0.16%) samples were non-negative in the second screening. The correlation between infection and age (30 years or older) and between infection and lower educational level (12 years or less) in the first and second screening was statistically significant. The seroprevalence of T. cruzi infection was higher in men in the first screening. In addition, 99.52% of the municipalities of Bahia had at least one case of CD. Livramento de Nossa Senhora and Salvador presented the highest disease prevalence and recurrence, respectively. CONCLUSIONS: The seroprevalence of T. cruzi infection in these populations was lower than that found in other studies in Brazil but was comparatively higher in densely-populated areas. The demographic characteristics of our population agreed with previous studies.

Relationship between diabetes mellitus and heart rate variability in community-dwelling elders.

BACKGROUND AND OBJECTIVE: Diabetes mellitus is one of the most common non-communicable diseases (NCDs) and may influence the autonomic nervous system. This study aims to analyze the autonomic control, through heart rate variability (HRV), from community-dwelling elders with (DM+) and without diabetes mellitus (DM-). MATERIALS AND METHODS: This cross-sectional study, in which 205 elders (≥ 60 years old), from the urban area of Aiquara municipality gave their written consent to participate. HRV data was collected through a Polar RS800CX monitor with a 5-min initial record at rest, followed by the command to quickly stand up. RESULTS: The mean age was 71 years (SD, 7.32). The population was mostly made up of women 121 (59%), with low or no schooling 123 (60%), and low income 166 (81%). HRV analysis in a frequency domain showed no difference when comparing the two groups of DM+ and DM-. Henceforth in a time domain, the rMSSD showed a median value of 16.09 (interquartile range, 9.91-30.68); pNN50 median of 0.79 (interquartile range, 0.00-6.62), with a statistical significance between the group of DM+ and DM-. CONCLUSIONS: There is a difference between the studied groups principally in what concerns the time domain, which reflects the parasympathetic activity, suggesting that elders with diabetes mellitus may have a worse parasympathetic control.

Avaliação do protocolo clínico e diretrizes terapêuticas para o tratamento para hepatite B crônica nas regiões nordeste e norte do Brasil / Analysis of clinical protocol and guidelines therapeutic for treatment for chronic hepatitis B in northeast Brazil and regions north

No Brasil o tratamento para Hepatite B cônica, tem sido disponibilizado pelo Sistema Único de Saúde há mais de 10 anos. O objetivo foi analisar o tratamento dos pacientes com hepatite B crônica, em dois Centros de Referência em Hepatites Virais na Região Nordeste e Norte do Brasil, comparando com o Protocolo Clínico e Diretrizes Terapêuticas da Hepatite B do Ministério da Saúde. Foram incluídos no estudo 527 pacientes em atendimento ambulatorial. No algoritmo 4.1 foi observado que existe uma dificuldade em seguir a recomendação do Ministério da Saúde, nos dois serviços de referência, 78,9% e 72% Região Nordeste e Norte respectivamente. O algoritmo 4.2, foi o algoritmo que apresentou no geral mais de 90% de seguimento na recomendação do Protocolo Clínico, devido que os pacientes são na sua grande maioria AgHBe negativo. O algoritmo 4.3 aproximadamente 85% dos pacientes da Região Nordeste estava dentro da recomendação do Protocolo Clínico para Hepatite B crônica, entretanto, nenhum paciente da Região Norte. O Protocolo Clínico de Diretrizes Terapêuticas para Hepatite B foi um grande passo e avanço. Uma ferramenta importantíssima dentro da realidade do tratamento para Hepatite B e foi possível incorporar novas drogas e indicadores de tratamento embasados na Medicina Baseada em Evidencias e nos Consensos Internacionais pelo Ministério da Saúde.

In Brazil the treatment for Hepatitis B conical, has been provided by the National Health System for over 10 years. The aim was to analyze the treatment of patients with chronic hepatitis B in two reference centers in Viral Hepatitis in the Northeast and North of Brazil, compared to the Clinical Protocol and Therapeutic Guidelines Hepatitis B of the Ministry of Health. The study included 527 patients in outpatient care. In algorithm 4.1 it was observed that there is a difficulty in following the recommendation of the Ministry of Health in two reference centers, 78.9% and 72% northeast and north respectively. The 4.2 algorithm, the algorithm was presented in general more than 90% follow-up on the recommendation of the Clinical Protocol because patients are mostly negative HBeAg. The algorithm 4.3 approximately 85% of patients in the Northeast was in the recommendation of the Clinical Protocol for chronic hepatitis B, however, no patients in the Northern Region. The Clinical Protocol Therapeutic Guidelines for Hepatitis B was a big step and advance. An important tool within the reality of treatment for hepatitis B and it was possible to incorporate new drugs and treatment indicators grounded in Evidence-Based Medicine and the International Consensus by the Ministry of Health.

Heterogenic colonization patterns by Leptospira interrogans in Rattus norvegicus from urban slums

Abstract We evaluated the renal colonization by Leptospira interrogans in Rattus norvegicus (rats), as it is the major natural reservoir of urban leptospirosis. We caught 72 R. norvegicus, out of which 32 were found to be positive for L. interrogans by immunofluorescence assay. From these rats, we selected 17 and divided them into six groups based on the mass-age/sex. We performed the immunohistochemistry test against L. interrogans in the kidney sections of the rats and systematically counted the colonized tubules (CTs) in 20 fields. The proportion of positive fields varied from 5% to 95%. The number of CTs in 20 fields varied from 0.5 to 85.5. These differences were not related to age or sex of the animals. The characterization of leptospiral colonization patterns in the natural reservoirs is important to better understand the host-pathogen interactions in leptospirosis.

Ionic imbalance and lack of effect of adjuvant treatment with methylene blue in the hamster model of leptospirosis

Leptospirosis in humans usually involves hypokalaemia and hypomagnesaemia and the putative mechanism underlying such ionic imbalances may be related to nitric oxide (NO) production. We previously demonstrated the correlation between serum levels of NO and the severity of renal disease in patients with severe leptospirosis. Methylene blue inhibits soluble guanylyl cyclase (downstream of the action of any NO synthase isoforms) and was recently reported to have beneficial effects on clinical and experimental sepsis. We investigated the occurrence of serum ionic changes in experimental leptospirosis at various time points (4, 8, 16 and 28 days) in a hamster model. We also determined the effect of methylene blue treatment when administered as an adjuvant therapy, combined with late initiation of standard antibiotic (ampicillin) treatment. Hypokalaemia was not reproduced in this model: all of the groups developed increased levels of serum potassium (K). Furthermore, hypermagnesaemia, rather than magnesium (Mg) depletion, was observed in this hamster model of acute infection. These findings may be associated with an accelerated progression to acute renal failure. Adjuvant treatment with methylene blue had no effect on survival or serum Mg and K levels during acute-phase leptospirosis in hamsters. .

Surveillance for leptospirosis in the Americas, 1996-2005: a review of data from ministries of health / Vigilancia de la leptospirosis en la Región de las Américas, de 1996 al 2005: análisis de los datos de los ministerios de salud

Objective. To characterize current leptospirosis reporting practices in the Americas.Methods. Information was collected from the official websites of national ministries ofhealth from the Americas region and two international organizations; personal communications;and three international morbidity databases. For all sources other than the morbiditydatabases, the review was limited to official reports citing clinically suspected and laboratoryconfirmed leptospirosis cases or deaths during the period 1996–2005.Results. A total of 73 out of 1 644 reports met the selection criteria and were included inthe analysis. Published leptospirosis data were available from half of the countries/sovereignterritories (24 out of 48), and 18 of them had mandatory notification policies for leptospirosis.The sum of the median number of leptospirosis cases notified annually by the 24 countries/territories was 4 713.5, but just three countries (Brazil, Costa Rica, and Cuba) accounted for83.1% (3 920 cases) of the notifications. Eight (16.7%) countries reported deaths due to leptospirosis.The sum of the median number of deaths reported annually for the eight countrieswas 380, but 349 (91.8%) were reported by Brazil.Conclusions. Notification practices in the Americas for leptospirosis are limited. Therefore,the numbers of cases and deaths reported are not representative for the region. The lack ofleptospirosis data for many countries/territories may reflect weaknesses in certain aspects ofnational surveillance systems, including mandatory reporting policies, clinical laboratory infrastructurefor performing case confirmation, and capacity to collect reported cases. Improvedsurveillance of leptospirosis cases and deaths in the Americas is needed to allow monitoring ofregional epidemiological patterns and to estimate the burden of this important disease.

Biological, biochemical and molecular features of Trypanosoma cruzi strains isolated from patients infected through oral transmission during a 2005 outbreak in the state of Santa Catarina, Brazil: its correspondence with the new T. cruzi Taxonomy Consensus (2009)

We examined strains of Trypanosoma cruzi isolated from patients with acute Chagas disease that had been acquired by oral transmission in the state of Santa Catarina, Brazil (2005) and two isolates that had been obtained from a marsupial (Didelphis aurita) and a vector (Triatoma tibiamaculata). These strains were characterised through their biological behaviour and isoenzymic profiles and genotyped according to the new Taxonomy Consensus (2009) based on the discrete typing unities, that is, T. cruzi genotypes I-VI. All strains exhibited the biological behaviour of biodeme type II. In six isolates, late peaks of parasitaemia, beyond the 20th day, suggested a double infection with biodemes II + III. Isoenzymes revealed Z2 or mixed Z1 and Z2 profiles. Genotyping was performed using three polymorphic genes (cytochrome oxidase II, spliced leader intergenic region and 24Sα rRNA) and the restriction fragment length polymorphism of the kDNA minicircles. Based on these markers, all but four isolates were characterised as T. cruzi II genotypes. Four mixed populations were identified: SC90, SC93 and SC97 (T. cruzi I + T. cruzi II) and SC95 (T. cruzi I + T. cruzi VI). Comparison of the results obtained by different methods was essential for the correct identification of the mixed populations and major lineages involved indicating that characterisation by different methods can provide new insights into the relationship between phenotypic and genotypic aspects of parasite behaviour.

Biological, biochemical and molecular features of Trypanosoma cruzi strains isolated from patients infected through oral transmission during a 2005 outbreak in the state of Santa Catarina, Brazil: its correspondence with the new T. cruzi Taxonomy Consensus (2009).

We examined strains of Trypanosoma cruzi isolated from patients with acute Chagas disease that had been acquired by oral transmission in the state of Santa Catarina, Brazil (2005) and two isolates that had been obtained from a marsupial (Didelphis aurita) and a vector (Triatoma tibiamaculata). These strains were characterised through their biological behaviour and isoenzymic profiles and genotyped according to the new Taxonomy Consensus (2009) based on the discrete typing unities, that is, T. cruzi genotypes I-VI. All strains exhibited the biological behaviour of biodeme type II. In six isolates, late peaks of parasitaemia, beyond the 20th day, suggested a double infection with biodemes II + III. Isoenzymes revealed Z2 or mixed Z1 and Z2 profiles. Genotyping was performed using three polymorphic genes (cytochrome oxidase II, spliced leader intergenic region and 24Sα rRNA) and the restriction fragment length polymorphism of the kDNA minicircles. Based on these markers, all but four isolates were characterised as T. cruzi II genotypes. Four mixed populations were identified: SC90, SC93 and SC97 (T. cruzi I + T. cruzi II) and SC95 (T. cruzi I + T. cruzi VI). Comparison of the results obtained by different methods was essential for the correct identification of the mixed populations and major lineages involved indicating that characterisation by different methods can provide new insights into the relationship between phenotypic and genotypic aspects of parasite behaviour.

Impacto da introdução de mídia eletrônica num curso de patologia geral / Impact of the introduction of electronic media in a general pathology course

Objetivo: Avaliar modificações implementadas recentemente num curso de Patologia Geral (PG), com vistas a incentivar a auto-instrução dos alunos por meio de recursos eletrônicos. Metodologia: Estudantes do curso de PG da Escola Bahiana de Medicina e Saúde Pública foram solicitados a preencher umquestionário sobre modificações implementadas na disciplina, entre elas a utilização de um CD-ROM elaborado e distribuído pela disciplina. Resultados: Foram avaliados 288 estudantes. A importância média dada ao CD-ROM foi de 8,45 ± 1,79, numa escala de 0 a 10, sendo esta a principal fonte de estudoutilizada por 97,2% dos estudantes para a prova prática. Os alunos que estudaram pelo CD apresentarammenor freqüência de notas baixas û consideradas inferiores a 6,0 (39,9% x 87,5%, P = 0,010) û e referiram conseguir identificar os processos gerais com maior freqüência (99,3% x 87,5%, P = 0,012) em relação aos que não utilizaram este método. 95,8% dos alunos acharam que o curso melhorou sua capacidade de reconhecer tecidos e órgãos ao microscópio. Conclusões: O CD-ROM utilizado oferece recursos que podem facilitar o processo ensino-aprendizagem, representando uma alternativa para o ensino integrado de PG.

Aim: To evaluate the modifications implemented in a General Pathology (GP) course, seeking to motivateself-instruction of the students through electronic resources. Methods: Students of the Escola Bahiana de Medicina e Saúde Pública were requested to answer a questionnaire in order to evaluate the modifications implemented in this discipline, specially the use of a CD-ROM elaborated and distributed in the course. Results: 288 students participated in the study. The mean importance given to the CD-ROM was of 8.45 ± 1.79, in a scale from 0 to 10. It was also the main study source for the practical evaluation, used by 97.2% of the students. The students who used the CD-ROM got low scores - considered inferior to 6.0 (39.9% x 87.5%, P = 0.010) - less frequently, and reported to be able of identifying the general pathologic processes more frequently (99.3% x 87.5%, P = 0.012) than the students that did not use this method.95.8% of the students thought that the course improved their capacity to recognize tissues or organs under the microscope. Conclusions: The CD-ROM offers resources that can facilitate the teaching-learning process, representing an alternative for the integrated teaching of GP.

A novel c.197T -> A variant among Brazilian neonates with glucose-6-phosphate dehydrogenase deficiency

Glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) deficiency is the most common enzyme deficiency worldwide, causing a spectrum of diseases including neonatal hyperbilirubinemia and acute or chronic hemolysis. We used the methemoglobin reduction test and G6PD electrophoresis to screen 655 neonates (354 females and 301 males) for common G6PD mutations in the city of Salvador in the Northeastern Brazilian state Bahia and found that 66 (10.1 percent) were G6PD-deficient (41 females and 25 males). The 66 (10.1 percent) G6PD-deficient neonates were assessed for the c.376 A -> G (exon 5) and c.202 G -> A (exon 4) mutations using the polymerase chain reaction and restriction enzyme fragment length polymorphism (PCR-RFLP) analysis and the results validated by DNA sequencing. Of the 66 G6PD-deficient neonates investigated we found that 54 (81.8 percent) presented the c.376 A -> G (p.Asn126Asp) and c.202 G -> A (p.Val68Met) mutations, two (3 percent) had the c.376 A -> G mutation only, two (3 percent) had the c.202 G -> A mutation only, five (7.6 percent) exhibited a previously unrecorded 197T -> A (p.Phe66Thr) substitution in exon 4 and three showed no mutations at any of these sites. Of the five neonates exhibiting the new 197T -> A (p.Phe66Thr) substitution, four (6.1 percent) also presented the c.202 G -> A and c.376 A -> G mutations and one (1.5 percent) had the c.[197T -> A / 202 G -> A] combination. We propose to name the new variant G6PD Bahia.

The dynamics of dengue virus serotype 3 introduction and dispersion in the state of Bahia, Brazil

By 2002, dengue virus serotype 1 (DENV-1) and DENV-2 had circulated for more than a decade in Brazil. In 2002, the introduction of DENV-3 in the state of Bahia produced a massive epidemic and the first cases of dengue hemorrhagic fever. Based on the standardized frequency, timing and location of viral isolations by the state's Central Laboratory, DENV-3 probably entered Bahia through its capital, Salvador, and then rapidly disseminated to other cities, following the main roads. A linear regression model that included traffic flow, distance from the capital and DENV-1 circulation (r² = 0.24, p = 0.001) supported this hypothesis. This pattern was not seen for serotypes already in circulation and was not seen for DENV-3 in the following year. Human population density was another important factor in the intensity of viral circulation. Neither DENV-1 nor DENV-2 fit this model for 2001 or 2003. Since the vector has limited flight range and vector densities fail to correlate with intensity of viral circulation, this distribution represents the movement of infected people and to some extent mosquitoes. This pattern may mimic person-to-person spread of a new infection.

The dynamics of dengue virus serotype 3 introduction and dispersion in the state of Bahia, Brazil.

By 2002, dengue virus serotype 1 (DENV-1) and DENV-2 had circulated for more than a decade in Brazil. In 2002, the introduction of DENV-3 in the state of Bahia produced a massive epidemic and the first cases of dengue hemorrhagic fever. Based on the standardized frequency, timing and location of viral isolations by the state's Central Laboratory, DENV-3 probably entered Bahia through its capital, Salvador, and then rapidly disseminated to other cities, following the main roads. A linear regression model that included traffic flow, distance from the capital and DENV-1 circulation (r2 = 0.24, p = 0.001) supported this hypothesis. This pattern was not seen for serotypes already in circulation and was not seen for DENV-3 in the following year. Human population density was another important factor in the intensity of viral circulation. Neither DENV-1 nor DENV-2 fit this model for 2001 or 2003. Since the vector has limited flight range and vector densities fail to correlate with intensity of viral circulation, this distribution represents the movement of infected people and to some extent mosquitoes. This pattern may mimic person-to-person spread of a new infection.