Blood donation in a large urban centre of southeast Brazil: a population-based study.

OBJECTIVES: This study aimed to estimate the prevalence and characterise potential blood donors and non-donors in a well-populated and representative urban area of Southeastern Brazil. BACKGROUND: Studies on blood donation usually evaluate individuals who donate. Population-based studies may contribute to characterise those who never reach the blood centre, trying to increase the range of donors. STUDY DESIGN AND METHODS: This was a secondary analysis of a population-based survey and a blood donor motivation study [Recipient Epidemiology and Donor Evaluation study (REDS II) International]. In a cross-sectional study 4047 individuals representing a metropolitan area answered the question 'Have you ever donated blood at least once in your life?'. The profiles ('Yes/No') were compared. Non-donors from this reference population were compared with donors of a local blood center, in a case control analysis. RESULTS: A total of 69·0% of the population had never donated blood and was composed mostly of women, younger than 30 years old, people not contributing to social security and not subscribing to newspapers. In the case-control study, the likelihood of donating was higher for: men, younger than 50 years old, longer time of education, married, participating in political campaigns and with a good self-perception of health. The factors associated with no blood donation were: self-reported mixed or white race/ethnicity, income higher than two minimum wages and belonging to trade union, political, religious/spiritual, or other social group and worse self perception of health. CONCLUSIONS: This population-based study allowed us to characterise a high proportion of people that never reaches the blood centre. The results may be used to diversify the donor profile, creating strategies to target those least likely to donate blood, as women, white people and those with higher income and purchasing power.

Mother-to-Child Transmission of Human T-Cell Lymphotropic Viruses-1/2: What We Know, and What Are the Gaps in Understanding and Preventing This Route of Infection.

Although human T-cell lymphotropic viruses (HTLV-1/2) were described over 30 years ago, they are relatively unknown to the public and even to healthcare personnel. Although HTLV-1 is associated with severe illnesses, these occur in only approximately 10% of infected individuals, which may explain the lack of public knowledge about them. However, cohort studies are showing that a myriad of other disease manifestations may trouble infected individuals and cause higher expenditures with healthcare. Testing donated blood for HTLV-1/2 started soon after reliable tests were developed, but unfortunately testing is not available for women during prenatal care. Vertical transmission can occur before or after birth of the child. Before birth, it occurs transplacentally or by transfer of virus during cesarean delivery, but these routes of infection are rare. After childbirth, viral transmission occurs during breastfeeding and increases with longer breastfeeding and high maternal proviral load. Unlike the human immunodeficiency virus types 1 and 2, HTLV is transmitted primarily through breastfeeding and not transplacentally or during delivery. In this study, we review what is currently known about HTLV maternal transmission, its prevention, and the gaps still present in the understanding of this process.

Relationship between social capital and test seeking among blood donors in Brazil.

BACKGROUND AND OBJECTIVES: Higher risk of HIV infection could be associated with test seeking, which is one motivation for donating blood. Cognitive social capital is defined as the social support, trust and co-operation that guide community behaviour. Structural social capital refers to an individual's participation in institutions and organizations. The association between social capital and test seeking was assessed. MATERIALS AND METHODS: A survey of over 7500 donors in three Brazilian blood centres was conducted. Test seeking was classified into four non-overlapping categories (non-test seeker, possible, presumed and self-disclosed test seekers) using one direct and two indirect questions. Social capital was summarized into cognitive and structural categorizations. Multivariable logistic regression analysis was performed. RESULTS: Compared with non-test seekers (62% of survey respondents), cognitive social capital was higher for each category of test seeking (OR=1.1, 7.4, 7.1, P<0.05 respectively). Male gender, lower education and lower income were also significantly associated with test seeking. CONCLUSION: As test seekers appear to have strong social networks, blood banks may leverage this to convince them to seek testing at other locations.

Hierarchical analysis of anaemia deferral in blood donor candidates: the individual in the population perspective.

BACKGROUND AND OBJECTIVES: Deferral due to anaemia is common in blood donor selection, mainly owing to iron deficiency. This study analysed the prevalence of anaemia, its individual and group-associated factors in 335,095 blood donor candidates in the Hemominas Foundation, a public blood centre in Minas Gerais State, Brazil. MATERIALS AND METHODS: For the hierarchical analysis, gender, self-reported skin colour and age were included as independent variables at the individual level. Second level variables included proportion of self-reported white, male proportion, prevalence of sickle cell trait and Human Development Index (HDI) for the cities where the blood centres were located. RESULTS: Deferral due to anaemia was 9.71% in the donor population in the present study. Differences among geographic areas throughout the State were observed; living in an area with lower HDI (P < 0.032), female gender and non-white skin colour (both P < 0.001) were significantly associated with anaemia. Cities with a lower HDI had higher prevalence rates of anaemia when compared with the others. Anaemia was more pronounced among female and non-white donors and in the northern part of the State. CONCLUSION: A high deferral of blood donors due to anaemia, mostly associated with poverty was observed and deserves attention from the public health perspective. Blood centres should consider the profile of donors and their geographic location when planning mobile blood collection or regional campaigns.

Transfusion-transmitted infectious diseases.

A spectrum of blood-borne infectious agents is transmitted through transfusion of infected blood donated by apparently healthy and asymptomatic blood donors. The diversity of infectious agents includes hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency viruses (HIV-1/2), human T-cell lymphotropic viruses (HTLV-I/II), Cytomegalovirus (CMV), Parvovirus B19, West Nile Virus (WNV), Dengue virus, trypanosomiasis, malaria, and variant CJD. Several strategies are implemented to reduce the risk of transmitting these infectious agents by donor exclusion for clinical history of risk factors, screening for the serological markers of infections, and nucleic acid testing (NAT) by viral gene amplification for direct and sensitive detection of the known infectious agents. Consequently, transfusions are safer now than ever before and we have learnt how to mitigate risks of emerging infectious diseases such as West Nile, Chikungunya, and Dengue viruses.

HLA class I alleles in HTLV-1-associated myelopathy and asymptomatic carriers from the Brazilian cohort GIPH.

INTRODUCTION AND OBJECTIVES: The development of HTLV-1-associated myelopathy (HAM/TSP) in HTLV-1-infected individuals is probably a multi-factor event, in which the immune system plays a crucial role. The efficiency of the host immunity seems to be one of the in vivo determining factors of the proviral load levels and is regulated by genes associated with MHC class I alleles (HLA). Protection or predisposition to HTLV-1-associated diseases according to individual HLA profile was shown in Japanese studies. The present work tested for HLA alleles previously related to protection or susceptibility to HTLV-1-associated myelopathy in a cohort study (GIPH) from Brazil. METHODS: A total of 93 HTLV-1-infected individuals participated in the study, as follows: 84 (90.3%) asymptomatic and 9 (9.7%) with HAM/TSP. Alleles related to protection (A*02, Cw*08) and susceptibility (B*07, Cw*08 and B*5401) were tested by the PCR-SSP method. RESULTS: Allele A*02 was more frequent in the asymptomatic group and in its absence, Cw*07 was correlated with HAM/TSP (P = 0.002). Allele B*5401 was not present in the Brazilian population. Alleles B*07 and Cw*08 were not different between the groups DISCUSSION: The presence of HLA-A2 elicits a stronger cytotoxic response, which is involved in the HTLV-1 proviral load reduction. This study confirmed a tendency of this allele to protect against HAM-TSP. Therefore, A*02 might be of interest for researches involved with HTLV-1 vaccine.

Spatial distribution of the Human T-Lymphotropic Virus types I and II (HTLV-I/II) infection among blood donors of Hemominas Foundation, Belo Horizonte, Minas Gerais State, Brazil, 1994-1996.

We conducted a cross-sectional study of the spatial distribution of HTLV-I/II infection among blood donors of Hemominas Foundation, living in Belo Horizonte, from 1994 to 1996. Study population (1,022) was composed by 533 cases (positive Western Blot (WB), indeterminate WB and ELISA positive without WB result) and a random sample of 489 non-cases (HTLV-I/II serum negative). Cases and non-cases were georeferenced using the exact or an approximation of the household address reported at the blood donation interview. Using multivariate analysis, cases with WB result are less likely to be reposition blood donors compared to voluntary ones (OR = 0.70; CI 95%: 0.50-0.99). Using the difference between univariate K functions, we found no evidence that cases and non-cases differ in their spatial distribution. We found no evidence that cases with and without WB result differ in the distance between their residence and Hemominas Foundation. No donors without WB result were georeferenced by the exact address. These donors could not have received the Hemominas letter inviting them to return to collect the second blood sample.

Spatial distribution of human and canine visceral leishmaniasis in Belo Horizonte, Minas Gerais State, Brasil, 1994-1997.

In this paper, we present spatial analysis of the association between all incidents cases of human Visceral Leishmaniasis and seropositive dogs, from 1994 to 1997 in Belo Horizonte, a large Brazilian city. We geocoded 158 human cases and 11,048 seropositive dogs and compared canine prevalence rates with Human Bayesian Incidence rates in the same areas. We also used Knox's test to evaluate the hypothesis of space-time clustering of human cases in the period. Additionally, we used Kernel's maps for seropositive dogs distribution and located the human cases in the resulting smooth maps. We concluded that human and dog rates are correlated. Also, the Visceral Leishmaniasis in Belo Horizonte spread quickly, but apart from the rates' magnitude, it has kept the same spatial pattern through time. We believe it is possible to use this technique to choose areas to implement control measures against Visceral Leishmaniasis in a more efficient way.

Human T lymphotropic virus type I (HTLV-I) infection in neurological patients in Salvador, Bahia, Brazil.

HTLV-I infection represents a major health concern in endemic areas throughout the world, such as Salvador, the main city of Bahia State, with socio-demographic characteristics similar to sub-Saharan African cities, located in the Northeast of Brazil. In order to provide an estimate of the frequency distribution, and range of neurological manifestations potentially related to HTLV-I infection in this city, we conducted a cross-sectional clinical-epidemiological study to determine the prevalence of this infection in patients with neurological diseases. Patients exhibiting vascular diseases, tumoral diseases or trauma were excluded. Over a period of 16 months, we studied 322 consecutive patients with chronic neurological diseases, who attended the neurological clinics of two major hospitals in Salvador. Overall, the prevalence of HTLV-I infection among the patients was 20.9% (67/320). However, the prevalence among the 104 patients with chronic myelopathy was 50.0% (52/104). It was observed that the major prevalence of HTLV-I was between the ages of 40 and 60 years with a female predominance. Our data indicate that, in Salvador city, HTLV-I is associated with chronic myelopathies or myeloneuropathies, which seem to be the only neurological diseases associated with HTLV-I.

HIV-1/2 indeterminate western blot results: follow-up of asymptomatic blood donors in Belo Horizonte, Minas Gerais, Brazil

A importancia clinica e de saude publica de resultados indeterminados em exames para HIV-1/2 e ainda dificil de avaliar em doadores de sangue voluntarios. Na Fundacao Hemominas e utilizado um teste de triagem (ELISA) que, se reativo, e seguido pelo Western blot (WB). Avaliamos nesse estudo 84 doadores que apresentavam ELISA repetidamente reativo, mas WB indeterminado. Dos 84 individuos, 16 (19 por cento) tinham historia de doencas sexualmente transmissiveis; 18/84 (21,4 por cento) informaram ter recebido ou pago por sexo; 3/84 (3,6 por cento) informaram contacto homosexual; 2/26 mulheres (7,6 por cento) tinham historia pregressa de multiplos abortos ilegais e 3/84 (3,6 por cento) tinham sidos transfundidos. Quatro de 62 doadores (6,5 por cento) tinham fator anti-nuclear (Hep2) positivo, com titulos de ate 1:640. Exame parasitologico revelou a presenca de ovos de S. mansoni nas fezes de 4/62 (6,4 por cento) e outros parasitas em 8/62 (12,9 por cento). Cinco individuos (5,9 por cento) apresentaram franca conversao para HIV-1/2 no WB; 43/84 (51,2 por cento) tinham resultados negativos na ultima visita, enquanto que 36/84 (42,9 por cento) permaneceram com o WB inderterminado. Concluimos que, embora pudessemos encontrar algumas condicoes associadas ao resultado inderminado para HIV-1/2 no WB e muitos doadores com historia pregressa de comportamento de risco, o significado da maioria dos resultados ainda necessita elucidacao

Erectile insufficiency as first symptom of HTLV I/II associated myelopathy. Case report.

A case of HTLV-I/II myelopathy in which the initial complaint was erectile insufficiency (EI) is reported. The only abnormalities found on the neurological exam were discrete weakness of the psoas and increased knee jerk reflexes. Diagnosis was made by demonstrating antibodies anti-HTLV I/II in the serum and cerebrospinal fluid (with the techniques of ELISA and Western blot), with confirmation by the polymerase chain reaction (PCR). EI can thus be the first symptom of HTLV-I/II infection and patients with EI of unknown etiology should be tested for HTLV-I/II in endemic areas.

Presence of human immunodeficiency virus (HIV) and T-lymphotropic virus type I and II (HTLV-I/II) in a haemophiliac population in Belo Horizonte, Brazil, and correlation with additional serological results.

The aim of this study was to determine the prevalence of human immunodeficiency virus type 1 (HIV-1) and human T lymphotropic virus types I and II (HTLV-I/II) infections in 226 haemophiliac patients treated at Fundação Hemominas in Belo Horizonte, Minas Gerais State, Brazil, and to verify association with other serological results. Patients positive for HTLV-I/II had also a neurological, haematological and ophthalmological evaluation. Fundação Hemominas offers comprehensive care for all haemophiliac patients in Minas Gerais. Thirty-six (15.9%) of the 226 patients showed reactive results to HIV-1 [ELISA, Abbott, USA, confirmed by Western blot (WB), Cambridge Biotech, USA, and/or immunofluorescence, Fiocruz, Brazil] and 16 (7.1%) had reactive sera to HTLV-I/II (ELISA, Ortho). Eleven of these 16 (4.9%) were positive, 3/16 (1.3%) were indeterminate and 2/16 (0.9%) were negative in the HTLV WB (Cambridge Biotech). Neurological, haematological and ophthalmological examination of 9/16 patients revealed no abnormality suggestive of HTLV disease. Of the 16 patients reactive to HTLV-I/II ELISA test, six (37.5%) were also positive to HIV-1 (chi 2 = 5.92; P = 0.01). Seropositivity for HTLV-I/II and HIV-1 was associated with advancing age and positive results for hepatitis C virus (HCV), Chagas' disease (T. cruzi infection) and syphilis. No association between the presence of HTLV with type and severity of haemophilia and hepatitis B results was detected. The prevalence of antibodies against HIV-1 is approximately three times that of HTLV-I/II and a patient positive for HTLV-I/II had a significantly increased risk of being positive for HIV-1, HCV and T. cruzi.

HTLV-I associated uveitis, myelopathy, rheumatoid arthritis and Sjögren's syndrome.

A 62 year-old white female presented with a 10-year-history of slowly progressive spastic paraparesis, pain and dysesthesia in the lower limbs and sphincter disturbance. A few years after the onset of the neurologic symptoms she developped migratory arthritis with swelling of the knees and pain on palpation of knees and fingers, dry eyes, mouth and skin. Two months before admission she presented bilateral nongranulomatous anterior uveitis. Examination revealed spastic paraparesis with bilateral Babinski sign, a decreased sensation level below L3, decreased vibration sense in the lower extremities, and a postural tremor of the upper limbs. Laboratory work-up disclosed HTLV-I positive tests in the blood and cerebrospinal fluid (CSF), and a mild pleocytosis in the CSF with a normal protein content. Nerve conduction velocity studies were normal. The present case shows the association of uveitis, arthritis and Sjögren's syndrome in a patient with tropical spastic paraparesis/human T-cell lymphotropic virus type I (HTLV-I) associated myelopathy (TSP/HAM), and illustrates the wide spectrum of clinical manifestations which may accompany this infection with this virus.

Children with adrenergic manifestations of envenomation after Tityus serrulatus scorpion sting are protected from early anaphylactic antivenom reactions.

The incidence of early anaphylactic reactions to scorpion antivenom given i.v. after Tityus serrulatus scorpion sting was evaluated in 103 children aged up to 15 years in Belo Horizonte, Brazil. Patients without adrenergic manifestations (Group 1, n = 28) were compared with those who presented systemic involvement that included adrenergic manifestations (Group 2, n = 75). Data were recorded on a proforma and the presence or absence of early anaphylactic reaction was cross-tabulated according to clinical features, sex, age and volume of antivenom used in the treatment. Unpaired Student's t-test was used to calculate significance of differences in age and volume of antivenom used. Multivariate logistic regression was used to determine the effects of clinical features and volume of antivenom as predictors of early anaphylactic reaction to antivenom treatment. Twelve (42.9%) of 28 children included in Group 1 presented early anaphylactic reactions compared with 6 (8%) of 75 children of Group 2 (OR = 8.63; 95% CI: 2.88, 25.7). The reactions were more severe in Group 1. There were no significant differences with respect to age and sex. After adjusting for clinical form, volume of antivenom was not significantly associated with presence of reactions (OR = 1.11; 95% CI: 0.70, 2.80 for each 5.0 ml of antivenom administered). The results show that children with adrenergic manifestations after T. serrulatus scorpion sting had significantly lower anaphylactic reactions to antivenom than those without these manifestations.

Epidemiology of Schistosoma mansoni infection in a low-endemic area in Brazil: clinical and nutritional characteristics.

A cross-sectional case-control study designed to evaluate the role of malnutrition in the association between the intensity of Schistosoma mansoni infection and clinical schistosomiasis, was conducted in an area with both low frequency of infection and low morbidity of schistosomiasis in Brazil. Cases (256) were patients with a positive stool examination for S. mansoni; their geometrical mean number of eggs/gram of feces was 90. Controls (256) were a random sample of the negative participants paired to the cases by age, sex and length of residence in the area. The clinical signs and symptoms found to be associated with S. mansoni infection, comparing cases and controls, were blood in stools and presence of a palpable liver. A linear trend in the relative odds of these signs and symptoms with increasing levels of infection was detected. Adjusting by the level of egg excretion, the existence of an interaction between palpable liver and ethnic group (white) was suggested. No differences in the nutritional status of infected and non-infected participants were found.

Exposure to acellular blood products and risk of HIV infection in hemophiliacs from Belo Horizonte, Brazil.

Results of a HIV prevalence study conducted in hemophiliacs from Belo Horizonte, Brazil are presented. History of exposure to acellular blood components was determined for the five year period prior to entry in the study, which occurred during 1986 and 1987. Patients with coagulations disorders (hemophilia A = 132, hemophilia B = 16 and coagulation disorders other than hemophilia = 16) were transfused with liquid cryoprecipitate, locally produced, lyophilized cryoprecipitate, imported from São Paulo (Brazil) and factor VIII and IX, imported from Rio de Janeiro (Brazil), Europe, and United States. Thirty six (22%) tested HIV seropositive. The univariate and multivariate analysis (logistic model) demonstrated that the risk of HIV infection during the study period was associated with the total units of acellular blood components transfused. In addition, the proportional contribution of the individual components to the total acellular units transfused, namely a increase in factor VIII/IX and lyophilized cryoprecipitate proportions, were found to be associated with HIV seropositivity. This analysis suggest that not only the total amount of units was an important determinant of HIV infection, but that the risk was also associated with the specific component of blood transfused.

Assessment of fibrin(ogen) degradation products in preeclampsia using immunoblot, enzyme-linked immunosorbent assay, and latex-based agglutination.

Plasma and serum from pregnant women with preeclampsia (N = 35) and normotensive pregnant (N = 71) and nonpregnant (N = 10) controls were screened for fibrin(ogen) degradation products (fibrinogen and cross-linked fibrin degradation products, and fibrin polymers) using three different assay systems (immunoblot, enzyme-linked immunosorbent assay [ELISA], and latex-bead agglutination assay). All tests showed statistically significant differences (P less than .05) between the preeclamptic patients and the other two groups (pregnant and nonpregnant women). The ELISA assay for total fibrin(ogen) degradation products was the most sensitive test, but was less specific than D-dimer latex. Eleven of the 35 preeclamptic women developed HELLP syndrome (hemolysis, elevated liver enzyme, and low platelet counts). Positive tests were as common in the 11 preeclamptic women who developed the syndrome as in the 24 who did not. These results suggest that fibrinolytic disorders are secondary pathophysiologic events in the course of preeclampsia, but further studies with a larger number of patients are needed.