Epidemiological methods for research with drug misusers: review of methods for studying prevalence and morbidity

Epidemiological studies of drug misusers have until recently relied on two main forms of sampling: probability and convenience. The former has been used when the aim was simply to estimate the prevalence of the condition and the latter when in depth studies of the characteristics, profiles and behaviour of drug users were required, but each method has its limitations. Probability samples become impracticable when the prevalence of the condition is very low, less than 0.5% for example, or when the condition being studied is a clandestine activity such as illicit drug use. When stratified random samples are used, it may be difficult to obtain a truly representative sample, depending on the quality of the information used to develop the stratification strategy. The main limitation of studies using convenience samples is that the results cannot be generalised to the whole population of drug users due to selection bias and a lack of information concerning the sampling frame. New methods have been developed which aim to overcome some of these difficulties, for example, social network analysis, snowball sampling, capture-recapture techniques, privileged access interviewer method and contact tracing. All these methods have been applied to the study of drug misuse. The various methods are described and examples of their use given, drawn from both the Brazilian and international drug misuse literature.

Portugal making a difference with children and families: the GADIF model

Portugal is a culture grounded in strong traditions and family. Yet, social changes like women returning to the workforce and a decreas ed national birth rate are impacting the traditional family structure and care giving environments of children. Female employment has been increasing steadily in P ortugal over the last three decades (Galego & Pereira, 2006) and the total fert ility rate decreasing from 4.1 to 2.8 (INE, 2006). Furthermore, extended family me mbers, like grandparents, no longer reside close by to their children and grandc hildren as in the past, because of a changing labor market. Many of the younger gen eration are leaving their rural communities to flock to urban areas because o f job opportunities, leaving behind older relatives who would have otherwise par ticipated in the daily care of children. Given these social and economic changes, children are spending more time in out-of-home care with non-familial caregive rs. Yet, government regulations and guidelines in early care and educat ion (ECCE) and early intervention (EI) are only just emerging; it contin ues to be a work in progress.

Implications of the Intervention Program for Physical Activity (IPPA) in the perception of illness and wellbeing in people with Multiple Sclerosis (MS)

The aim of this study is to examine the implications of the IPPA in the perception of illness and wellbeing in MS patients. Methods - This is a quasi experimental study non-randomized study with 24 MS patients diagnosed at least 1 year before, and with an EDSS score of under 7. We used the IPPA in 3 groups of eight people in 3 Portuguese hospitals (Lisbon, Coimbra, and Porto). The sessions were held once a week for 90 minutes, over a period of 7 weeks. The instruments used were: We asked the subjects the question “Please classify the severity of your disease?” and used the Personal Wellbeing Scale (PWS) at the beginning (time A) and end (time B) of the IPPA. We used the SPSS version 20. A non-parametric statistical hypothesis test (Wilcoxon test) was used for the variable analysis. The intervention followed the recommendations of the Helsinki Declaration. Results – The results suggest that there are differences between time A and B, the perception of illness decreased (p<0.08), while wellbeing increased (p<0.01). Conclusions: The IPPA can play an important role in modifying the perception of disease severity and personal wellbeing.

Heterophoria, fusional amplitudes and stereoacuity in school aged children

The stability of binocular vision depends on good fusional amplitudes and its measurements provide information about the patient’s ability to cope with a deviation. However, weak correlations between fusional amplitudes and angle of deviation have been reported in the literature. There are no uniform normative values of fusional amplitudes, even though standards for vergence have been established since 1940s. Aims: 1) Determine the prevalence of heterephoria; 2) Determine the relationship between heterophoria, fusional amplitudes and stereoacuity in children.

A prospective study with children whose mothers had dengue during pregnancy

Dengue congenital disease was not confirmed in 10 children whose mothers had the infection during pregnancy. The fetal sera presented anti-dengue IgG antibodies which progressively declined, and disappeared after 8 months. IgM antibodies to dengue were not observed in the sera. Other normal data suggesting the healthy state of the children included: absence of malformations, pregnancy time, Apgar index, weight, and placenta aspect

Tinea capitis: study of asymptomatic carriers and sick adolescents, adults and elderly who live with children with the disease

Tinea capitis is a dermatophyte infection that occurs mainly in childhood; there are few reports, in Brazil, in adolescents and adults. The detection of asymptomatic carriers is of great importance in the disease control. From February 1998 to February 1999, a study was performed at the outpatient Dermatologic Unit of Instituto de Puericultura e Pediatria Martagão Gesteira (Universidade Federal do Rio de Janeiro, Brasil) to verify the frequency of asymptomatic carriers and tinea capitis between 79 adolescents, adults and elderly who lived in the same household of 56 children (0-12 years) with tinea capitis. Of these, one female and one male adults (2.5%) were asymptomatic carriers and the cultures revealed Trichophyton tonsurans and Microsporum canis respectively. One female adolescent and two female adults (3.8%) had tinea capitis and all cultures revealed Trichophyton tonsurans. The study has shown that adolescents and adults who live in the same household of children with tinea capitis may be sick or asymptomatic carriers.

Polymerase Chain Reaction Screening for Fungemia and/or Invasive Fungal Infections in Patients with Hematologic Malignancies

INTRODUCTION: Invasive fungal infections (IFIs) are a life-threatening complication in patients with hematologic malignancies, mainly in acute leukemia patients, following chemotherapy. IFI incidence is increasing, and associated mortality remains high due to unreliable diagnosis. Antifungal drugs are often limited by inadequate antimicrobial spectrum and side effects. Thus, the detection of circulating fungal DNA has been advocated as a rapid, more sensitive diagnostic tool. PATIENTS AND METHODS: Between June 01 and January 03, weekly blood samples (1,311) were screened from 193 patients undergoing intensive myelosuppressive or immunosuppressive therapy. IFI cases were classified according to European Organization for Research and Treatment of Cancer/Mycoses Study Group criteria. Fungal DNA was extracted from whole blood and amplified using polymerase chain reaction (PCR) published primers that bind to the conserved regions of the fungal 18S rRNA gene sequence. In our study, two or more consecutive positive samples were always associated with fungal disease. RESULTS: PCR screening predicted the development of IFI to be 17 days (median). This test had a specificity of 91.1% and a sensitivity of 75%. IFI incidence was 7.8%. DISCUSSION: Therefore, our results confirm the potential usefulness of PCR serial screening and the clinical applicability in everyday routine. PCR screening offers a noninvasive repeatable aid to the diagnosis of IFI.

An outbreak of scalp white piedra in a Brazilian children day care

White piedra is a superficial mycosis caused by Trichosporon spp. that affects the hair shaft of any part of the body. It is presented an outbreak of scalp white piedra seen in 5.8% of the children frequenting a day care in Northeastern of São Paulo State, Brazil. Mycological exam and culture identified T. cutaneum in all five cases, and scanning electron microscopy of nodules around hair shaft infected by Trichosporon spp. is demonstrated comparing them with those of black piedra and with nits of Pediculous capitis.

The importance of physical education classes in pre-school children

The purpose of this study was to analyse differences between total physical activity (TPA) and moderate-to-vigorous PA (MVPA) of pre-school children during daily school hours when they attended the physical education class (PED) and school days without PE class (NPED) and to assess the contribution of PE classes to TPA in school hours. The sample was composed of 193 pre-school healthy children (96 girls) aged from three to five years old and was conducted between February and December of 2008. Children wore accelerometers for at least four consecutive days during school hours. Data were analysed with specific software, age-specific counts-per-minute cut-off points and a 5 s epoch were used. Independent and general linear model repeated measures were used to assess differences between gender and differences between different days within each gender, respectively. Boys engaged more MVPA than girls (P < 0.05). During PED, pre-school children engaged significantly more in TPA and MVPA than during NPED (P < 0.05). PE class contributed, on average, 27.7% for the TPA and 32.8% of daily MVPA during PED in both gender. The results of this study suggest that structured PA such as a PE class increased the daily TPA and MVPA level of pre-school children.

Identification of respiratory virus in infants with congenital heart disease by comparison of different methods

Respiratory virus infections are the main cause of infant hospitalization and are potentially severe in children with congenital heart disease (CHD). Rapid and sensitive diagnosis is very important to early introduction of antiviral treatment and implementation of precautions to control transmission, reducing the risk of nosocomial infections. In the present study we compare different techniques in the diagnosis of respiratory viruses in CHD infants. Thirty-nine samples of nasopharyngeal aspirate were obtained from CHD infants with symptoms of respiratory infection. The Multiplex PCR (Seeplex® RV 12 ACE Detection) driven to the detection of 12 respiratory viruses was compared with the direct immunofluorescence assay (DFA) and PCR, both targeting seven respiratory viruses. The positivity found by DFA, Multiplex and PCR was 33.3%, 51.3% and 48.7%, respectively. Kappa index comparing DFA and Multiplex, DFA and PCR and PCR and Multiplex PCR was 0.542, 0.483 and 0.539, respectively. The concordance between techniques was considered moderate. Both Multiplex PCR (p = 0.001) and PCR (p = 0.002) detected significantly more respiratory virus than DFA. As the performance of the tests may vary, the combination of two or more techniques may increase diagnostic sensitivity favoring the diagnosis of co-infections, early introduction of antiviral therapy and implementation of appropriate measures.

ESTABLISHING THE REFERENCE RANGE FOR T LYMPHOCYTES SUBPOPULATIONS IN ADULTS AND CHILDREN FROM BRAZIL

SUMMARY In Brazil, the existing reference values for T-lymphocytes subsets are based on data originated in other countries. There is no local information on normal variation for these parameters in Brazilian adults and children. We evaluated the normal variation found in blood donors from five large Brazilian cities, in different regions, and in children living in Salvador, and Rio de Janeiro. All samples were processed by flow cytometry. The results were analyzed according to region, gender, and lifestyle of blood donors. A total of 641 adults (63% males), and 280 children (58% males) were involved in the study. The absolute CD3+, and CD4+ cells count were significantly higher for females (adults and children). Higher CD4+ cell count in adults was associated with smoking, while higher CD8+ count was found among female children. Higher counts, for all T-cells subsets, were detected in blood donors from southeast / south regions while those living in the northern region had the lowest values. Individuals from midwestern and northeastern regions had an intermediate count for all these cells subsets. However, these differences did not reach statistical significance. In Brazil, gender and smoking, were the main determinants of differences in T-lymphocytes reference values.

Improving Influenza Surveillance in Portuguese Preschool Children by Parents' Report

Influenza surveillance is usually based on nationally organized sentinel networks of physicians and on hospital reports. This study aimed to test a different report system, based on parents' phone contact to the research team and in home collection of samples by a dedicated team. The identification of influenza and other respiratory viruses in children who attended a Hospital Emergency Department was also recorded. Real-time PCR and reverse transcription PCR were performed for influenza A and B, parainfluenza 1-4, adenovirus, human metapneumovirus, respiratory syncytial virus A and B, rhinovirus, enterovirus, group 1 coronaviruses, group 2 coronaviruses, and human bocavirus. One hundred children were included, 64 from the day care centers and 36 from the Hospital. Overall, 79 samples were positive for at least one respiratory virus. Influenza A (H3) was the virus most frequently detected: 25 cases, 20 of these in children under 5 years of age (ten from day care centers and ten who went to the hospital) which was higher than those reported by the National Influenza Surveillance Programme for this age. CONCLUSION: The results obtained in this study suggest that a surveillance system based on parents' reports could complement the implanted system of the National Influenza Surveillance Programme.

Seroprevalence and sociocultural conditionants of Chagas disease in school aged children of marginal zones of Asunción

Chagas disease is becoming a public health problem in Latin America due to the wide distribution, the high prevalence, the magnitude of the damage caused and the difficulties to control it. In Paraguay, the disease is mainly distributed in the departments of Paraguari, Cordillera and Central. Prevalence in marginal zones, where migrations from rural populations and endemic areas make possible the urbanization of the disease, has no been studied yet. This is a descriptive study with a cross-sectional sampling and a probabilistic system recruitment carried out in school aged children from marginal zones of Asuncion to determine the prevalence of Chagas' disease. Serological methods, parasite isolation and questionnaires were used to achieve the goals. Nine hundred and fifty three children were studied to determine the prevalence of Chagas' disease in marginal zones which was 1.4%.

Toxoplasma antibody and stool parasites in public school children, Rolândia, Paraná, Brazil

The occurrence of toxoplasmosis and enteroparasitosis was studied in 434 children from elementary schools in the rural and urban areas of Rolândia, Paraná State, Brazil. Sera and fecal samples from all the students were submitted to IFA for Toxoplasma gondii and coproparasitological tests, respectively. The children were tested by Amsler grid and 72 of them were examined for the presence of lesions compatible with ocular toxoplasmosis. Some variables were tested but none showed increased risk for toxoplasmosis. The distribution according to sex and age and also same other variables are presented and discussed. Correlations between Amsler's grid test, toxoplama RIFI, occurrence of eyes lesions and enteroparasitosis are also considered.

Serum levels of interleukin-6, tumor necrosis factor-alpha and interferon-gama in infants with and without dengue

This study compared the serum levels of IL-6, TNF-alpha and IFN-gamma, in children under 1 year of age with and without dengue. Sera were collected from a total of 41 children living in the Department of Antioquia, Colombia (27 patients with dengue and 14 controls). The results showed higher cytokine levels in children with dengue than without dengue, with statistically significant differences for IL-6 and IFN-gamma. No statistically significant differences were found between clinical forms, although IL-6 and IFN-gamma levels were higher in dengue fever cases than in dengue hemorrhagic fever cases. On the other hand, TNF-alpha levels were higher in dengue hemorrhagic fever than in dengue fever. The levels of IL-6 and TNF-alpha were higher in secondary infection than in primary infection, although IFN-gamma levels were higher in primary infection. These results suggest that IL-6, TNF-alpha and IFN-gamma are involved in dengue infection independently of the clinical form.