Birth Prevalence and Natural History of Congenital Cytomegalovirus Infection in a Highly Seroimmune Population

Background. The natural history of congenital cytomegalovirus (CMV) infection is scarcely known in populations with high maternal CMV seroprevalence. This study evaluated the birth prevalence, clinical findings at birth, and hearing outcome in CMV-infected children from such a population. Methods. Consecutively born infants were screened for the presence of CMV in urine and/or saliva specimens during the first 2 weeks after birth. Neonatal clinical findings were recorded, and CMV-infected children were tested to document hearing function during follow-up. A subset of mothers of CMV-infected infants were prenatally tested for the presence of anti-CMV immunoglobulin G antibodies. Results. Congenital CMV infection was confirmed in 87 (1.08%; 95% confidence interval [CI], 0.86%-1.33%) of 8047 infants. Seven infants (8.1%; 95% CI, 3.3%-15.9%) had at least 1 clinical finding suggestive of CMV infection, and 4 (4.6%; 95% CI, 1.3%-11.3%) had 13 findings of systemic disease. Sensorineural hearing loss was found in 5 (8.6%; 95% CI, 2.9%-19.0%) of 58 children tested at a median age of 21 months. Bilateral profound hearing loss was observed in 2 children, and the hearing threshold was 160 decibels in all 5 children with hearing loss, including 2 children born to mothers with probable nonprimary CMV infection. Conclusions. The results of this large newborn screening study in a population with high CMV seroimmunity provide additional evidence that congenital CMV disease occurs in populations with high seroprevalence rates, with a similar incidence of CMV-related hearing loss to that reported in the offspring of women from populations in developed countries with lower rates of seroimmunity to CMV.

A nationwide population-based study of migraine in Brazil

The aim of this study was to estimate the 1-year prevalence of migraine and the degree of the association of migraine with some sociodemographic characteristics of a representative sample of the adult population of Brazil. This was a cross-sectional, population-based study. Telephone interviews were conducted on 3848 people, aged 18-79 years, randomly selected from the 27 States of Brazil. The estimated 1-year gender- and age-adjusted prevalence of migraine was 15.2%. Migraine was 2.2 times more prevalent in women, 1.5 times more in subjects with > 11 years of education, 1.59 times more in subjects with income of < 5 Brazilian Minimum Wages per month, and 1.43 times more in those who do not do any physical exercise. The overall prevalence of migraine in Brazil is 15.2%. Migraine is significantly more prevalent in women, subjects with higher education, with lower income, and those who do not exercise regularly, independently of their body mass index.

A Nationwide Population-Based Study of Tension-Type Headache in Brazil

To estimate the 1-year prevalence of tension-type headache (TTH) and the degree of the association of TTH with some sociodemographic characteristics of a representative sample of the adult population of Brazil. This was an observational, cross-sectional, population-based study. We conducted telephone interviews on 3848 people, aged 18-79 years, randomly selected from the 27 states of Brazil. Trained lay interviewers administered the structured questionnaire. It included questions about the sociodemographic characteristics of the population, as well as questions about headache. The degree of the association was calculated through prevalence ratios, adjusted with Poisson regression by gender, age, years of education, marital status, household income, job status, body mass index (BMI), and physical exercise. The estimated 1-year gender- and-age-adjusted prevalence of TTH was 13.0% (95% CI: 11.8-14.2%); 15.4% in males and 9.5% in females. The prevalence of probable TTH was 22.6% (95% CI: 21.1-24.1%). Most (86.2%) subjects reported episodic TTH; 6.4% had chronic TTH. The prevalence was higher at 18-29 years of age (16.2%). TTH was 1.6 times more prevalent in men, and 1.54 times more in subjects with more than 11 years of education. There was no significant association of TTH with marital or job status, household income, BMI, and physical activity. This is the first nationwide epidemiological study of TTH in Brazil. The overall prevalence of TTH in Brazil is low, at 13%. TTH is significantly more prevalent in males and subjects with higher education level.

Chronic daily headache in Brazil: a nationwide population-based study

The objectives of this study were to estimate the 1-year prevalence of chronic daily headache (CDH) and the degree of the association of CDH with some sociodemographic characteristics of the adult population of Brazil. This was a cross-sectional, population-based study. We conducted telephone interviews with 3848 people, aged 18-79 years, randomly selected from the 27 States of Brazil. The degree of the association was calculated through prevalence ratios, adjusted with Poisson regression by gender, age and some sociodemographic factors. The estimated 1-year gender- and age-adjusted prevalence of CDH was 6.9%. CDH was 2.4 times more prevalent in women, 1.72 times more in unemployed, 1.63 times more in subjects with high household income and two times greater in those who did not exercise. The overall prevalence of CDH in Brazil is high. CDH is significantly more prevalent in women, the unemployed, subjects with higher income, and in those who do not exercise.

Systemic lupus erythematosus: Association with KIR and SLC11A1 polymorphisms, ethnic predisposition and influence in clinical manifestations at onset revealed by ancestry genetic markers in an urban Brazilian population

Systemic lupus erythematosus (SLE) is an autoimmune disorder of the connective tissue with a wide and heterogeneous spectrum of manifestations, with renal and neurological involvement usually related to worse prognosis. SLE more frequently affects females of reproductive age, and a high prevalence and renal manifestation seem to be associated with non-European ethnicity. The present study aims to investigate candidate loci to SLE predisposition and evaluate the influence of ethnic ancestry in the disease risk and clinical phenotypic heterogeneity of lupus at onset. Samples represented by 111 patients and 345 controls, originated from the city of Belem, located in the Northern Region of Brazil, were investigated for polymorphisms in HLA-G, HLA-C, SLC11A1, MTHFR, CASP8 and 15 KIR genes, in addition to 89 Amerindian samples genotyped for SLC11A1. We also investigated 48 insertion/deletion ancestry markers to characterize individual African, European and Amerindian ancestry proportions in the samples. Predisposition to SLE was associated with GTGT deletion at the SLC11A1 3`UTR, presence of KIR2DS2 +/KIR2DS5 +/KIR3DS1 + profile, increased number of stimulatory KIR genes, and European and Amerindian ancestries. The ancestry analysis ruled out ethnic differences between controls and patients as the source of the observed associations. Moreover, the African ancestry was associated with renal manifestations. Lupus (2011) 20, 265-273.

Canine population dynamics: the potential effect of sterilization campaigns

Objective. To analyze, through mathematical modeling, the potential ability of sterilization campaigns to reduce the population density of pet dogs. Methods. Mathematical models were constructed to simulate the canine population dynamics and project the results of control strategies based on several sterilization rates. Results. Even at high sterilization rates (for example, 0.80 year(-1)), it would take approximately 5 years to reduce density by 20%. Even so, other sources of population growth, such as the importing of dogs from other geographic areas, could outweigh the effects of a sterilization program. Conclusions. A program`s effectiveness is contingent upon not only on the sterilization rate, but also the rate of population growth. Sterilization campaigns may potentially reduce population density, but this reduction may not be immediately evident.

Population structure and mouse-virulence of Toxoplasma gondii in Brazil

Recent studies found that isolates of Toxoplasma gondii from Brazil were biologically and genetically different from those in North America and Europe. However, to date only a small number of isolates have been analysed from different animal hosts in Brazil. In the present study DNA samples of 46 T. gondii isolates from cats in 11 counties in Sao Paulo state, Brazil were genetically characterised using 10 PCR restriction fragment length polymorphism markers including SAG1, SAG2, SAG3, STUB, GRA6, c22-8, c29-2, L358, PKI and Apico. An additional marker, CS3, that locates on chromosome VIIa and has previously been shown to be linked to acute virulence of T. gondii was also used to determine its association to virulence in mice. Genotyping of these 46 isolates revealed a high genetic diversity with 20 genotypes but no clonal Type I, II or III lineage was found. Two of the 46 isolates showed mixed infections. Combining genotyping data in this study with recent reported results from chickens, dogs and cats in Brazil (total 125 isolates) identified 48 genotypes and 26 of these genotypes had single isolates. Four of the 48 genotypes with multiple isolates identified from different hosts and locations are considered the common clonal lineages in Brazil. These lineages are designated as Types BrI, BrII, BrIII and BrIV. These results indicate that the T. gondii population in Brazil is highly diverse with a few successful clonal lineages expanded into wide geographical areas. In contrast to North America and Europe, where the Type II clonal lineage is overwhelmingly predominant, no Type II strain was identified from the 125 Brazil isolates. Analysis of mortality rates in infected mice indicates that Type BrI is highly virulent, Type BrIII is non-virulent, whilst Type BrII and BrIV lineages are intermediately virulent. In addition, allele types at the CS3 locus are strongly linked to mouse-virulence of the parasite. Thus, T. gondii has an epidemic population structure in Brazil and the major lineages have different biological traits. (C) 2007 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Modeling the Dynamics of Viral Evolution Considering Competition Within Individual Hosts and at Population Level: The Effects of Treatment

We consider two viral strains competing against each other within individual hosts (at cellular level) and at population level (for infecting hosts) by studying two cases. In the first case, the strains do not mutate into each other. In this case, we found that each individual in the population can be infected by only one strain and that co-existence in the population is possible only when the strain that has the greater basic intracellular reproduction number, R (0c) , has the smaller population number R (0p) . Treatment against the one strain shifts the population equilibrium toward the other strain in a complicated way (see Appendix B). In the second case, we assume that the strain that has the greater intracellular number R (0c) can mutate into the other strain. In this case, individual hosts can be simultaneously infected by both strains (co-existence within the host). Treatment shifts the prevalence of the two strains within the hosts, depending on the mortality induced by the treatment, which is, in turn, dependent upon the doses given to each individual. The relative proportions of the strains at the population level, under treatment, depend both on the relative proportions within the hosts (which is determined by the dosage of treatment) and on the number of individuals treated per unit time, that is, the rate of treatment. Implications for cases of real diseases are briefly discussed.

Avian Infectious Bronchitis Virus in Brazil: A Highly Complex Virus Meets a Highly Susceptible Host Population

Infectious bronchitis (IB) is a highly aggressive disease for poultry in terms of symptoms and economic losses, and the control of this disease is difficult if flocks are not protected against type-specific challenges by the Avian infectious bronchitis virus (IBV). This article summarizes data presented by the author at the Workshop on Infectious Bronchitis 2009 on IB and IBV, including future developments on the field.

Periodontal attachment loss in an untreated isolated population of Brazil

Background: The aim of this study was to assess the prevalence, extent, and severity of clinical attachment loss (CAL) and to investigate the association of demographic, socioeconomic, and behavioral risk indicators with CAL in an untreated isolated population in Brazil. Methods: All subjects aged >= 12 years were identified by a census. Participants were submitted to a full-mouth clinical examination of six sites per tooth and were interviewed using a structured, written questionnaire. Results: Among the 214 subjects who were interviewed and examined clinically, CAL >= 5 mm in at least one site was observed in 8% of the 12- to 19-year-olds and in all dentate subjects >= 50 years of age; the age-dependent prevalence of CAL >= 7 mm in at least one site ranged from 5% among 12- to 19-year-olds to 83% among subjects >= 50 years old. Multivariate analysis identified plaque (odds ratio [OR] = 2.8), supragingival calculus (OR = 2.9 to 10.6), age >= 30 years (OR = 11.4), and smoking (OR = 2.4) as risk indicators for CAL >= 5 mm and smoking (OR = 8.2) as a risk indicator for CAL >= 7 mm. Conclusions: CAL is highly prevalent in this isolated population. The high occurrence of CAL in young age groups and the confirmation of traditional risk indicators for CAL in this study suggest that other factors, such as host susceptibility, may be needed to explain the high levels of CAL found. Age and behavioral factors were risk indicators associated significantly with the CAL found in this population and may be useful indicators of high-risk subjects for periodontal diseases.