Publications by authors named "Ulisses R Montarroyos"

17 Publications

  • Page 1 of 1

Neurodevelopment in Children Exposed to Zika Virus: What Are the Consequences for Children Who Do Not Present with Microcephaly at Birth?

Viruses 2021 Jul 22;13(8). Epub 2021 Jul 22.

Pós-Graduação em Ciências da Saúde, Universidade de Pernambuco, Recife 50100-010, Brazil.

The relation of Zika virus (ZIKV) with microcephaly is well established. However, knowledge is lacking on later developmental outcomes in children with evidence of maternal ZIKV infection during pregnancy born without microcephaly. The objective of this analysis is to investigate the impact of prenatal exposure to ZIKV on neuropsychomotor development in children without microcephaly. We evaluated 274 children including 235 ZIKV exposed and 39 controls using the Bayley-III Scales of Infant and Toddler Development (BSIDIII) and neurological examination. We observed a difference in cognition with a borderline p-value ( = 0.052): 9.4% of exposed children and none of the unexposed control group had mild to moderate delays. The prevalence of delays in the language and motor domains did not differ significantly between ZIKV-exposed and unexposed children (language: 12.3% versus 12.8%; motor: 4.7% versus 2.6%). Notably, neurological examination results were predictive of neurodevelopmental delays in the BSIDIII assessments for exposed children: 46.7% of children with abnormalities on clinical neurological examination presented with delay in contrast to 17.8% among exposed children without apparent neurological abnormalities ( = 0.001). Overall, our findings suggest that relative to their unexposed peers, ZIKV-exposed children without microcephaly are not at considerably increased risk of neurodevelopmental impairment in the first 42 months of life, although a small group of children demonstrated higher frequencies of cognitive delay. It is important to highlight that in the group of exposed children, an abnormal neuroclinical examination may be a predictor of developmental delay. The article contributes to practical guidance and advances our knowledge about congenital Zika.
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http://dx.doi.org/10.3390/v13081427DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8402706PMC
July 2021

Prevalence of hepatitis A in the capitals of the States of North, Southeast and South regions of Brazil: decrease in prevalence and some consequences.

Rev Inst Med Trop Sao Paulo 2021 26;63:e34. Epub 2021 Apr 26.

Universidade de Pernambuco, Faculdade de Ciências Médicas, Recife, Pernambuco, Brazil.

Hepatitis A virus (HAV) infection has been considered one of the leading causes of acute hepatitis. The aim of the present study was to estimate the prevalence of HAV among children and adolescents in a population-based study in the capitals of the States of the North, Southeast and South of Brazil and identify predictive factors for the infection. A multi-stage sampling was used to select subjects aged between 5-9 and 10-19 years. Individual and household levels aside from the level of variables in the areas were collected. The outcome was the total IgG antibodies to HAV levels detected using a commercial Enzyme Immuno Assay (EIA). The associations between HAV and the independent variables were assessed using the odds ratio. A multilevel analysis was performed by GLLAMM using the Stata software. The prevalence of HAV infection in the 5-9 and 10-19 age groups was 28.7% and 67.5%, respectively for the North, 20.6% and 37.7%, for the Southeast and 18.9% and 34.5% for the South Region. The prevalence of HAV increased according to age in all sites. Variables related to education at the individual level (North and South), family and area level (South and Southeast) and family income level (Southeast and South) were independently associated with HAV infection. This emphasizes the need for individualized strategies to prevent the infection.
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http://dx.doi.org/10.1590/S1678-9946202163034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8075615PMC
May 2021

Early epilepsy in children with Zika-related microcephaly in a cohort in Recife, Brazil: Characteristics, electroencephalographic findings, and treatment response.

Epilepsia 2020 03 17;61(3):509-518. Epub 2020 Feb 17.

University of Pernambuco, Recife, Brazil.

Objective: To estimate the incidence of epilepsy in children with Zika-related microcephaly in the first 24 months of life; to characterize the associated clinical and electrographic findings; and to summarize the treatment responses.

Methods: We followed a cohort of children, born during the 2015-2016 Zika virus (ZIKV) epidemic in Brazil, with congenital microcephaly and evidence of congenital ZIKV infection on neuroimaging and/or laboratory testing. Neurological assessments were performed at ≤3, 6, 12, 15, 18, 21, and 24 months of life. Serial electroencephalograms were performed over the first 24 months.

Results: We evaluated 91 children, of whom 48 were female. In this study sample, the cumulative incidence of epilepsy was 71.4% in the first 24 months, and the main type of seizure was infantile spasms (83.1%). The highest incidence of seizures occurred between 3 and 9 months of age, and the risk remained high until 15 months of age. The incidence of infantile spasms peaked between 4 and 7 months and was followed by an increased incidence of focal epilepsy cases after 12 months of age. Neuroimaging results were available for all children, and 100% were abnormal. Cortical abnormalities were identified in 78.4% of the 74 children evaluated by computed tomography and 100% of the 53 children evaluated by magnetic resonance imaging. Overall, only 46.1% of the 65 children with epilepsy responded to treatment. The most commonly used medication was sodium valproate with or without benzodiazepines, levetiracetam, phenobarbital, and vigabatrin.

Significance: Zika-related microcephaly was associated with high risk of early epilepsy. Seizures typically began after the third month of life, usually as infantile spasms, with atypical electroencephalographic abnormalities. The seizure control rate was low. The onset of seizures in the second year was less frequent and, when it occurred, presented as focal epilepsy.
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http://dx.doi.org/10.1111/epi.16444DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7155083PMC
March 2020

Perinatal analyses of Zika- and dengue virus-specific neutralizing antibodies: A microcephaly case-control study in an area of high dengue endemicity in Brazil.

PLoS Negl Trop Dis 2019 03 11;13(3):e0007246. Epub 2019 Mar 11.

Aggeu Magalhães Institute, Oswaldo Cruz Foundation (FIOCRUZ), Recife, Pernambuco, Brazil.

Laboratory confirmation of Zika virus (ZIKV) infection during pregnancy is challenging due to cross-reactivity with dengue virus (DENV) and limited knowledge about the kinetics of anti-Zika antibody responses during pregnancy. We described ZIKV and DENV serological markers and the maternal-fetal transfer of antibodies among mothers and neonates after the ZIKV microcephaly outbreak in Northeast Brazil (2016). We included 89 microcephaly cases and 173 neonate controls at time of birth and their mothers. Microcephaly cases were defined as newborns with a particular head circumference (2 SD below the mean). Two controls without microcephaly were matched by the expected date of delivery and area of residence. We tested maternal serum for recent (ZIKV genome, IgM and IgG3 anti-NS1) and previous (ZIKV and DENV neutralizing antibodies [NAbs]) markers of infection. Multiple markers of recent or previous ZIKV and DENV infection in mothers were analyzed using principal component analysis (PCA). At delivery, 5.6% of microcephaly case mothers and 1.7% of control mothers were positive for ZIKV IgM. Positivity for ZIKV IgG3 anti-NS1 was 8.0% for case mothers and 3.5% for control mothers. ZIKV NAbs was slightly higher among mothers of cases (69.6%) than that of mothers of controls (57.2%; p = 0.054). DENV exposure was detected in 85.8% of all mothers. PCA discriminated two distinct components related to recent or previous ZIKV infection and DENV exposure. ZIKV NAbs were higher in newborns than in their corresponding mothers (p<0.001). We detected a high frequency of ZIKV exposure among mothers after the first wave of the ZIKV outbreak in Northeast Brazil. However, we found low sensitivity of the serological markers to recent infection (IgM and IgG3 anti-NS1) in perinatal samples of mothers of microcephaly cases. Since the neutralization test cannot precisely determine the time of infection, testing for ZIKV immune status should be performed as early as possible and throughout pregnancy to monitor acute Zika infection in endemic areas.
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http://dx.doi.org/10.1371/journal.pntd.0007246DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6428350PMC
March 2019

Prevalence of Obstructive Sleep Apnea and Obesity Among Middle-Aged Women: Implications for Exercise Capacity.

J Clin Sleep Med 2018 09 15;14(9):1471-1475. Epub 2018 Sep 15.

Sleep and Heart Laboratory, Pronto Socorro Cardiológico de Pernambuco (PROCAPE) da Universidade de Pernambuco, Brasil.

Study Objectives: The aim of the current study was to evaluate the association between obstructive sleep apnea (OSA) and exercise capacity in middle-aged women.

Methods: Consecutive middle-aged female subjects without cardiovascular disease, aged 45 to 65 years, from two gynecological clinics underwent detailed clinical evaluation, portable sleep study, and treadmill exercise test.

Results: We studied 232 women (age: 55.6 ± 5.2 years; body mass index [BMI]: 28.0 ± 4.8 kg/m). OSA (apnea-hypopnea index ≥ 5 events/h) was diagnosed in 90 (39%) and obesity (BMI > 30 kg/m) in 76 (33%) women, respectively. Participants with OSA were older, had a higher BMI, and an increased frequency of arterial hypertension compared to women without OSA. Multiple logistic regression models were used to evaluate the association between OSA and exercise capacity, controlling for traditional risk factors including BMI, age, hypertension, diabetes, and sedentary lifestyle. In multivariate analysis, the presence of obesity without OSA was associated with low exercise capacity (odds ratio [OR] 2.88, 95% confidence interval [CI] 1.02-8.11, = .045), whereas the presence of OSA without obesity was not (OR 1.07, 95% CI 0.31-3.69, = .912). However, the coexistence of obesity and OSA increased markedly the odds of reduction in exercise capacity (OR 9.40, CI 3.79-23.3, < .001).

Conclusions: Obesity and OSA are common conditions in middle-aged women and may interact to reduce exercise capacity. These results highlight the importance of obesity control programs among women, as well as the diagnosis of comorbid OSA in older women.
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http://dx.doi.org/10.5664/jcsm.7316DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6134251PMC
September 2018

Serological markers of hepatitis B and C in patients with HIV/AIDS and active tuberculosis.

J Med Virol 2016 Jun 1;88(6):996-1002. Epub 2015 Dec 1.

Departamento de Saúde Coletiva, Centro de Pesquisas Aggeu Magalhães/FIOCRUZ, Recife, Brazil.

Infection with hepatitis B virus (HBV) and C virus (HCV) are common in patients with HIV/AIDS and tuberculosis (TB). This is a cross-sectional study with patients infected with HIV/AIDS and active TB in Recife, Brazil, aiming to verify the prevalence of markers for HBV: antibody to hepatitis B core antigen (anti-HBc); and HCV: antibody to hepatitis C virus (anti-HCV) by chemiluminescence, and to identify the frequency of associated factors. Data were collected through questionnaires, and blood was drawn from patients for analysis. We used the chi-square test and the Fisher exact test when necessary. We conducted a bivariate logistic regression analysis and the magnitude of the associations was expressed as odds ratio (OR) with a confidence interval of 95%. Among 166 patients studied with HIV/AIDS and active TB, anti-HBc was positive in 61 patients [36.7%; 95%CI (29.4-44.6%)] and anti-HCV in 11[6.6%; 95%CI (3.4-11.5%)]. In the logistic regression analysis, male sex, and age ≥40 years were independent factors associated with the occurrence of anti-HBc. In conclusion, we verified a high frequency of HBV contact marker and a low frequency of HCV markers in patients with HIV/AIDS and TB in Recife.
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http://dx.doi.org/10.1002/jmv.24432DOI Listing
June 2016

Population-Based Multicentric Survey of Hepatitis B Infection and Risk Factors in the North, South, and Southeast Regions of Brazil, 10-20 Years After the Beginning of Vaccination.

Am J Trop Med Hyg 2015 Dec 26;93(6):1341-1348. Epub 2015 Oct 26.

A population-based hepatitis survey was carried out to estimate the prevalence of hepatitis B virus (HBV) infection and its predictive factors for the state capitals from the north, south, and southeast regions of Brazil. A multistage cluster sampling was used to select, successively, census tracts, blocks, households, and residents in the age group 10-69 years in each state capital. The prevalence of hepatitis B surface antigen (HBsAg) was lower than 1% in the north, southeast, and south regions. Socioeconomic condition was associated with HBV infection in north and south regions. Variables related to the blood route transmission were associated with HBV infection only in the south whereas those related to sexual behavior were associated with HBV infection in the north and south regions. Drug use was associated in all regions, but the type of drug differed. The findings presented herein highlight the diversity of the potential transmission routes for hepatitis B transmission in Brazil. In one hand, it reinforces the importance of national control strategies of large impact already in course (immunization of infants, adolescents, and adults up to 49 years of age and blood supply screening). On the other hand, it shows that there is still room for further control measures targeted to different groups within each region.
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http://dx.doi.org/10.4269/ajtmh.15-0216DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4674256PMC
December 2015

Comparison between potential risk factors for cardiovascular disease in people living with HIV/AIDS in areas of Brazil.

J Infect Dev Ctries 2015 Sep 27;9(9):988-96. Epub 2015 Sep 27.

Universidade de Pernambuco, Recife, Brazil.

Introduction: Coronary heart disease and its risk factors depend on genetic characteristics, behaviors, and habits, all of which vary in different regions. The use of antiretroviral therapy (ARV) has increased the survival of people living with HIV/AIDS (PLWHA), who begin to present mortality indicators similar to the general population. This study aimed to compare the prevalence of factors potentially associated with coronary heart disease in three cohorts of PLWHA from three different regions of Brazil.

Methodology: The study population was composed of participants of the cohorts of Pernambuco, Goiás, and Rio Grande do Sul states. In these sites, adult patients attending reference centers for treatment of HIV/AIDS were consecutively enrolled.

Results: Pernambuco and Goiás had a higher proportion of males and of individuals with high-risk high-density lipoprotein (HDL). Pernambuco also had a greater proportion of individuals with hypertension, elevated triglycerides, and CD4 counts below 200 cells/mm(3). Lower education was more frequent in Rio Grande do Sul, and the use of cocaine was higher in this state.

Conclusions: The results confirm the importance of risk factors for coronary heart disease in PLHIV and highlight differences in the three cohorts. Specific measures against smoking and sedentary lifestyle, avoidance of advanced stages of immunosuppression, and appropriate treatment of dyslipidemia and dysglicemia are urgently needed to cope with the disease in Brazil.
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http://dx.doi.org/10.3855/jidc.5867DOI Listing
September 2015

Prevalence and risk factors of Hepatitis C virus infection in Brazil, 2005 through 2009: a cross-sectional study.

BMC Infect Dis 2013 Feb 1;13:60. Epub 2013 Feb 1.

Universidade de Pernambuco, Faculdade de Ciências Médicas de Pernambuco, Hospital Universitário Oswaldo Cruz, Rua Arnóbio Marques, 310, Santo Amaro, CEP: 50100-130, Recife, PE, Brazil.

Background: Hepatitis C chronic liver disease is a major cause of liver transplant in developed countries. This article reports the first nationwide population-based survey conducted to estimate the seroprevalence of HCV antibodies and associated risk factors in the urban population of Brazil.

Methods: The cross sectional study was conducted in all Brazilian macro-regions from 2005 to 2009, as a stratified multistage cluster sample of 19,503 inhabitants aged between 10 and 69 years, representing individuals living in all 26 State capitals and the Federal District. Hepatitis C antibodies were detected by a third-generation enzyme immunoassay. Seropositive individuals were retested by Polymerase Chain Reaction and genotyped. Adjusted prevalence was estimated by macro-regions. Potential risk factors associated with HCV infection were assessed by calculating the crude and adjusted odds ratios, 95% confidence intervals (95% CI) and p values. Population attributable risk was estimated for multiple factors using a case-control approach.

Results: The overall weighted prevalence of hepatitis C antibodies was 1.38% (95% CI: 1.12%-1.64%). Prevalence of infection increased in older groups but was similar for both sexes. The multivariate model showed the following to be predictors of HCV infection: age, injected drug use (OR = 6.65), sniffed drug use (OR = 2.59), hospitalization (OR = 1.90), groups socially deprived by the lack of sewage disposal (OR = 2.53), and injection with glass syringe (OR = 1.52, with a borderline p value). The genotypes 1 (subtypes 1a, 1b), 2b and 3a were identified. The estimated population attributable risk for the ensemble of risk factors was 40%. Approximately 1.3 million individuals would be expected to be anti-HCV-positive in the country.

Conclusions: The large estimated absolute numbers of infected individuals reveals the burden of the disease in the near future, giving rise to costs for the health care system and society at large. The known risk factors explain less than 50% of the infected cases, limiting the prevention strategies. Our findings regarding risk behaviors associated with HCV infection showed that there is still room for improving strategies for reducing transmission among drug users and nosocomial infection, as well as a need for specific prevention and control strategies targeting individuals living in poverty.
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http://dx.doi.org/10.1186/1471-2334-13-60DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3574834PMC
February 2013

Risk factors for default from tuberculosis treatment in HIV-infected individuals in the state of Pernambuco, Brazil: a prospective cohort study.

BMC Infect Dis 2011 Dec 16;11:351. Epub 2011 Dec 16.

Department of Tropical Medicine, Universidade Federal de Pernambuco, Recife, Brazil.

Background: Concomitant treatment of Human Immunodeficiency Virus (HIV) infection and tuberculosis (TB) presents a series of challenges for treatment compliance for both providers and patients. We carried out this study to identify risk factors for default from TB treatment in people living with HIV.

Methods: We conducted a cohort study to monitor HIV/TB co-infected subjects in Pernambuco, Brazil, on a monthly basis, until completion or default of treatment for TB. Logistic regression was used to calculate crude and adjusted odds ratios, 95% confidence intervals and P-values.

Results: From a cohort of 2310 HIV subjects, 390 individuals (16.9%) who had started treatment after a diagnosis of TB were selected, and data on 273 individuals who completed or defaulted on treatment for TB were analyzed. The default rate was 21.7% and the following risk factors were identified: male gender, smoking and CD4 T-cell count less than 200 cells/mm3. Age over 29 years, complete or incomplete secondary or university education and the use of highly active antiretroviral therapy (HAART) were identified as protective factors for the outcome.

Conclusion: The results point to the need for more specific actions, aiming to reduce the default from TB treatment in males, younger adults with low education, smokers and people with CD4 T-cell counts < 200 cells/mm3. Default was less likely to occur in patients under HAART, reinforcing the strategy of early initiation of HAART in individuals with TB.
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http://dx.doi.org/10.1186/1471-2334-11-351DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3297544PMC
December 2011

An evaluation of factors associated with taking and responding positive to the tuberculin skin test in individuals with HIV/AIDS.

BMC Public Health 2011 Sep 5;11:687. Epub 2011 Sep 5.

Department of Tropical Medicine, Universidade Federal de Pernambuco, Recife, Brazil.

Background: The tuberculin skin test (TST) is still the standard test for detecting latent infection by M tuberculosis (LTBI). Given that the Brazilian Health Ministry recommends that the treatment of latent tuberculosis (LTBI) should be guided by the TST results, the present study sets out to describe the coverage of administering the TST in people living with HIV at two referral health centers in the city of Recife, where TST is offered to all patients. In addition, factors associated with the non-application of the test and with positive TST results were also analyzed.

Methods: A cross-sectional study was carried out with HIV patients, aged 18 years or over, attending outpatient clinics at the Correia Picanço Hospital/SES/PE and the Oswaldo Cruz/UPE University Hospital, who had been recommended to take the TST, in the period between November 2007 and February 2010. Univariate and multivariate logistic regression analyses were carried out to establish associations between the dependent variable - taking the TST (yes/no), at a first stage analysis, and the independent variables, followed by a second stage analysis considering a positive TST as the dependent variable. The odds ratio was calculated as the measure of association and the confidence interval (CI) at 95% as the measure of accuracy of the estimate.

Results: Of the 2,290 patients recruited, 1087 (47.5%) took the TST. Of the 1,087 patients who took the tuberculin skin test, the prevalence of TST ≥ 5 mm was 21.6% among patients with CD4 ≥ 200 and 9.49% among those with CD4 < 200 (p = 0.002). The patients most likely not to take the test were: men, people aged under 39 years, people with low educational levels and crack users. The risk for not taking the TST was statiscally different for health service. Patients who presented better immunity (CD4 ≥ 200) were more than two and a half times more likely to test positive that those with higher levels of immunodeficiency (CD4 < 200).

Conclusions: Considering that the TST is recommended by the Brazilian health authorities, coverage for taking the test was very low. The most serious implication of this is that LTBI treatment was not carried out for the unidentified TST-positive patients, who may consequently go on to develop TB and eventually die.
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http://dx.doi.org/10.1186/1471-2458-11-687DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3223927PMC
September 2011

Is it better to be rich in a poor area or poor in a rich area? A multilevel analysis of a case-control study of social determinants of tuberculosis.

Int J Epidemiol 2009 Oct 4;38(5):1285-96. Epub 2009 Aug 4.

Departamento de Medicina Tropical, Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil.

Background: Tuberculosis is known to have socio-economic determinants at individual and at area levels, but it is not known whether they are independent, whether they interact and their relative contributions to the burden of tuberculosis.

Methods: A case-control study was conducted in Recife, Brazil, to investigate individual and area social determinants of tuberculosis, to explore the relationship between determinants at the two levels and to calculate their relative contribution to the burden of tuberculosis. It included 1452 cases of tuberculosis diagnosed by the tuberculosis services and 5808 controls selected at random from questionnaires completed for the demographic census. Exhaustive information on social factors was collected from cases, using the questionnaire used in the census. Socio-economic information for areas was downloaded from the census. Multilevel logistic regression investigated individual and area effects.

Results: There was a marked and independent influence of social variables on the risk of tuberculosis, both at individual and area levels. At individual level, being aged >or=20, being male, being illiterate, not working in the previous 7 days and possessing few goods, all increased the risk of tuberculosis. At area level, living in an area with many illiterate people and where few households own a computer also increased this risk; individual and area levels did not appear to interact. Twice as many cases were attributable to social variables at individual level than at area level.

Conclusions: Although individual characteristics are the main contributor to the risk of tuberculosis, contextual characteristics make a substantial independent contribution.
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http://dx.doi.org/10.1093/ije/dyp224DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2755128PMC
October 2009

Population-based multicentric survey of hepatitis B infection and risk factor differences among three regions in Brazil.

Am J Trop Med Hyg 2009 Aug;81(2):240-7

Faculdade de Ciências Médicas de Pernambuco, Hospital Universitário Oswaldo Cruz, Universidade de Pernambuco, Recife, Pernambuco, Brazil.

This multicentric population-based study in Brazil is the first national effort to estimate the prevalence of hepatitis B (HBV) and risk factors in the capital cities of the Northeast, Central-West, and Federal Districts (2004-2005). Random multistage cluster sampling was used to select persons 13-69 years of age. Markers for HBV were tested by enzyme-linked immunosorbent assay. The HBV genotypes were determined by sequencing hepatitis B surface antigen (HBsAg). Multivariate analyses and simple catalytic model were performed. Overall, 7,881 persons were included; < 70% were not vaccinated. Positivity for HBsAg was less than 1% among non-vaccinated persons and genotypes A, D, and F co-circulated. The incidence of infection increased with age with similar force of infection in all regions. Males and persons having initiated sexual activity were associated with HBV infection in the two settings; healthcare jobs and prior hospitalization were risk factors in the Federal District. Our survey classified these regions as areas with HBV endemicity and highlighted the risk factors differences among the settings.
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August 2009

Selection bias: neighbourhood controls and controls selected from those presenting to a Health Unit in a case control study of efficacy of BCG revaccination.

BMC Med Res Methodol 2007 Feb 23;7:11. Epub 2007 Feb 23.

Department of Mother and Child Health, Federal University of Pernambuco, Recife, Brasil.

Background: In most case control studies the hardest decision is the choice of the control group, as in the ideal control group the proportion exposed is the same as in the population that produced the cases.

Methods: A comparison of two control groups in a case control study of the efficacy of BCG revaccination. One group was selected from subjects presenting to the heath unit the case attended for routine prevention and care; the second group was selected from the neighbourhood of cases. All Health Units from which controls were selected offered BCG revaccination. Efficacy estimated in a randomized control trial of BCG revaccination was used to establish that the neighbourhood control group was the one that gave unbiased results.

Results: The proportion of controls with scars indicating BCG revaccination was higher among the control group selected from Health Unit attenders than among neighbourhood controls. This excess was not removed after control for social variables and history of exposure to tuberculosis, and appears to have resulted from the fact that people attending the Health Unit were more likely to have been revaccinated than neighbourhood controls, although we can not exclude an effect of other unmeasured variables.

Conclusion: In this study, controls selected from people presenting to a Health Unit overrepresented exposure to BCG revaccination. Had the results from the HU attenders control group been accepted this would have resulted in overestimation of vaccine efficacy. When the exposure of interest is offered in a health facility, selection of controls from attenders at the facility may result in over representation of exposure in controls and selection bias.
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http://dx.doi.org/10.1186/1471-2288-7-11DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1810541PMC
February 2007

Risk factors for treatment delay in pulmonary tuberculosis in Recife, Brazil.

BMC Public Health 2005 Mar 18;5:25. Epub 2005 Mar 18.

Departamento de Medicina Tropical, Universidade Federal de Pernambuco, Brazil.

Background: Tuberculosis is still a great challenge to public health in Brazil and worldwide. Early detection followed by effective therapy is extremely important in controlling the disease. Recent studies have investigated reasons for delays in treatment, but there is no agreed definition of what constitutes an "acceptable" delay. This study investigates factors associated with total delay in treatment of tuberculosis.

Methods: A cohort of adult cases of pulmonary tuberculosis diagnosed over a two-year period was studied. Patients were interviewed on entry, reporting the duration of symptoms before the start of treatment, and sputum and blood samples were collected. It was decided that sixty days was an acceptable total delay. Associations were investigated using univariable and multivariable analysis and the population attributable fraction was estimated.

Results: Of 1105 patients, 62% had a delay of longer than 60 days. Age, sex, alcoholism and difficulty of access were not associated with delays, but associations were found in the case of unemployment, having given up smoking, having lost weight and being treated in two of the six health districts. The proportion attributable to: not being an ex-smoker was 31%; unemployment, 18%; weight loss, 12%, and going to the two worst health districts, 25%.

Conclusion: In this urban area, delays seem to be related to unemployment and general attitudes towards health. Although they reflect the way health services are organized, delays are not associated with access to care.
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http://dx.doi.org/10.1186/1471-2458-5-25DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1084352PMC
March 2005

Antibody isotype responses in Balb/c mice immunized with the cytoplasmic repetitive antigen and flagellar repetitive antigen of Trypanosoma cruzi.

Mem Inst Oswaldo Cruz 2003 Sep 29;98(6):823-5. Epub 2003 Oct 29.

Departamento de Imunologia, Centro de Pesquisas Aggeu Magalhães-Fiocruz, 50670-420 Recife, PE, Brasil.

In the present report we analyzed the levels of IgG1, IgG2a, IgG2b and IgG3 isotypes from Balb/c mice immunized with cytoplasmic repetitive antigen (CRA), and flagellar repetitive antigen (FRA) of Trypanosoma cruzi. The immunization was done by subcutaneous route three times (20 days apart) and the analysis was performed 14 days after each treatment. CRA-immunized mice produced high levels of all IgG isotypes, mainly IgG3 and IgG1. FRA-immunization elicited only high levels of IgG1.
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http://dx.doi.org/10.1590/s0074-02762003000600019DOI Listing
September 2003
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