Human T-cell lymphotropic virus type 1 infection among pregnant women in northeastern Brazil

Integrative and Multidisciplinary Care for People Living With Human T-Cell Lymphotropic Virus in Bahia, Brazil: 20 Years of Experience

Brazil is home to the highest absolute number of human T-cell lymphotropic virus type-1 (HTLV-1)-infected individuals worldwide; the city of Salvador, Bahia, has the highest prevalence of HTLV-1 infection in Brazil. Due to the complex nature of several diseases associated with this retrovirus, a multidisciplinary health care approach is necessary to care for people living with HTLV-1. The Bahia School of Medicine and Public Health’s Integrative Multidisciplinary HTLV Center (CHTLV) has been providing support to people living with HTLV and their families since 2002, striving to ensure physical and mental well-being by addressing biopsychosocial aspects, providing clinical care and follow-up, including to pregnant/postpartum women, as well as comprehensive laboratory diagnostics, psychological therapy, and counseling to family members. To date, CHTLV has served a total of 2,169 HTLV-infected patients. The average patient age is 49.8 (SD 15.9) years, 70.3% are female, most are considered low-income and have low levels of education. The majority (98.9%) are HTLV-1 cases, and approximately 10% have been diagnosed with tropical spastic paraparesis/HTLV-1-associated myelopathy (TSP/HAM), while 2.2% have infective dermatitis and 1.1% have adult T-cell lymphoma. In all, 178 pregnant/postpartum women [mean age: 32.7 (±6.5) years] have received care at CHTLV. Regarding vertical transmission, 53% of breastfed infants screened for HTLV tested positive in their second year of life, nearly 18 times the rate found in non-breastfed infants. This article documents 20 years of experience in implementing an integrative and multidisciplinary care center for people living with HTLV in Bahia, Brazil. Still, significant challenges remain regarding infection control, and HTLV-infected individuals continue to struggle with the obtainment of equitable and efficient healthcare.

Clinical and Public Health Implications of Human T-Lymphotropic Virus Type 1 Infection

Human T-lymphotropic virus type 1 (HTLV-1) is estimated to affect 5 to 10 million people globally and can cause severe and potentially fatal disease, including adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The burden of HTLV-1 infection appears to be geographically concentrated, with high prevalence in discrete regions and populations. While most high-income countries have introduced HTLV-1 screening of blood donations, few other public health measures have been implemented to prevent infection or its consequences. Recent advocacy from concerned researchers, clinicians, and community members has emphasized the potential for improved prevention and management of HTLV-1 infection. Despite all that has been learned in the 4 decades following the discovery of HTLV-1, gaps in knowledge across clinical and public health aspects persist, impeding optimal control and prevention, as well as the development of policies and guidelines. Awareness of HTLV-1 among health care providers, communities, and affected individuals remains limited, even in countries of endemicity. This review provides a comprehensive overview on HTLV-1 epidemiology and on clinical and public health and highlights key areas for further research and collaboration to advance the health of people with and at risk of HTLV-1 infection.

Prevalence of human T-lymphotropic virus type 1 and 2 (HTLV-1/-2) infection in pregnant women in Brazil: a systematic review and meta-analysis

Human T-lymphotropic virus type 1 (HTLV-1) infection may cause serious disease, while pathogenicity of HTLV-2 is less certain. There are no screening or surveillance programs for HTLV-1/-2 infection in Brazil. By performing this systematic review, we aimed to estimate the prevalence of HTLV-1/-2 infections in pregnant women in Brazil. This review included cohort and cross-sectional studies that assessed the presence of either HTLV-1/-2 infection in pregnant women in Brazil. We searched BVS/LILACS, Cochrane Library/CENTRAL, EMBASE, PubMed/MEDLINE, Scopus, Web of Science and gray literature from inception to August 2020. We identified 246 records in total. Twenty-six of those were included in the qualitative synthesis, while 17 of them were included in the meta-analysis. The prevalence of HTLV-1 in Brazilian pregnant women, as diagnosed by a positive screening test and a subsequent positive confirmatory test, was 0.32% (95% CI 0.19-1.54), while of HTLV-2 was 0.04% (95% CI 0.02-0.08). Subgroup analysis by region showed the highest prevalence in the Northeast region (0.60%; 95% CI 0.37-0.97) for HTLV-1 and in the South region (0.16%; 95% CI 0.02-1.10) for HTLV-2. The prevalence of HTLV-1 is much higher than HTLV-2 infection in pregnant Brazilian women with important differences between regions. The prevalence of both HTLV-1/-2 are higher in the Northeast compared to Center-West region.

Brazilian Protocol for Sexually Transmitted Infections 2020: human T-cell lymphotropic virus (HTLV) infection

This article addresses the Human T-lymphotropic virus (HTLV). This subject comprises the Clinical Protocol and Therapeutic Guidelines for Comprehensive Care for People with Sexually Transmitted Infections, published by the Brazilian Ministry of Health. HTLV-1/2 infection is a public health problem globally, and Brazil has the largest number of individuals living with the virus. HTLV-1 causes several clinical manifestations of neoplasm (adult T-cell leukemia/lymphoma) and inflammatory nature, such as HTLV-1-associated myelopathy and other manifestations such as uveitis, arthritis, and infective dermatitis. These pathologies have high morbidity and mortality and negatively impact the quality of life of infected individuals. This review includes relevant information for health authorities professionals regarding viral transmission, diagnosis, treatment, and monitoring of individuals living with HTLV-1 and 2 in Brazil. HTLV-1/2 transmission can occur through blood transfusion and derivatives, injectable drug use, organ transplantation, unprotected sexual intercourse, and vertical transmission.

Extracellular Vesicles in HTLV-1 Communication: The Story of an Invisible Messenger

Human T-cell lymphotropic virus type 1 (HTLV-1) infects 5-10 million people worldwide and is the causative agent of adult T-cell leukemia/lymphoma (ATLL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) as well as other inflammatory diseases. A major concern is that the most majority of individuals with HTLV-1 are asymptomatic carriers and that there is limited global attention by health care officials, setting up potential conditions for increased viral spread. HTLV-1 transmission occurs primarily through sexual intercourse, blood transfusion, intravenous drug usage, and breast feeding. Currently, there is no cure for HTLV-1 infection and only limited treatment options exist, such as class I interferons (IFN) and Zidovudine (AZT), with poor prognosis. Recently, small membrane-bound structures, known as extracellular vesicles (EVs), have received increased attention due to their potential to carry viral cargo (RNA and proteins) in multiple pathogenic infections (i.e., human immunodeficiency virus type I (HIV-1), Zika virus, and HTLV-1). In the case of HTLV-1, EVs isolated from the peripheral blood and cerebral spinal fluid (CSF) of HAM/TSP patients contained the viral transactivator protein Tax. Additionally, EVs derived from HTLV-1-infected cells (HTLV-1 EVs) promote functional effects such as cell aggregation which enhance viral spread. In this review, we present current knowledge surrounding EVs and their potential role as immune-modulating agents in cancer and other infectious diseases such as HTLV-1 and HIV-1. We discuss various features of EVs that make them prime targets for possible vehicles of future diagnostics and therapies.

Implications of human T-lymphotropic virus in pregnancy: A case report and a review of the diagnostic criteria and management proposal

Human T-lymphotropic virus (HTLV) is considered to be the most highly oncogenic existing virus, being the cause of several fatal diseases such as adult T cell leukemia-lymphoma (ATL) and HTLV-I-associated myelopathy (HAM). The main transmission methods are unprotected sexual intercourse, vertical transmission and breastfeeding and direct exposure to infected blood or tissue. The identification of infected mothers prior to delivery is a highly important step in preventing mother to child transmission. Universal antenatal screening for HTLV is not recommended in Romania, although there are sufficient data demonstrating the risk of vertical transmission. We present the case of an HTLV-1-infected pregnant woman, with an aim to highlight: i) points of strategy for the management of HTLV during pregnancy; ii) the particularities of the course of pregnancy; and iii) the aspects that show the importance of knowing the status regarding the HTLV infection antepartum. The case was particular due to the ascendant proviral load during the pregnancy period, which led to the initiation of antiretroviral therapy and the particular pregnancy outcome with preterm rupture of membranes and fetal growth restriction. According to current recommendations, pregnant women infected with HTLV-1 should be advised to refrain from donating blood, body organs, or other tissues. There is no evidence of the number of individuals infected with this virus in Romania at present, and the diagnosis can only occur by chance. A specific treatment or immunization for HTLV infection does not currently exist, thus preventive methods are the only tool to reduce the prevalence and mortality of this infection.

Distribution of Human T-Lymphotropic Virus (HTLV) and Hepatitis C Co-infection in Bahia, Brazil

Both Human T-lymphotropic virus type 1 (HTLV-1) and hepatitis C virus (HCV) are endemic in Brazil. In Salvador, the capital of the state of Bahia, 2% and 1.5% of the general population is infected with HTLV-1 or HCV. This study aimed to estimate the prevalence and the distribution of HTLV/HCV coinfection in Bahia. This cross-sectional study was conducted at the Central Laboratory of Public Health for the state of Bahia (LACEN-BA). All samples in the LACEN database submitted to serological testing for anti-HCV (chemiluminescence) and anti-HTLV-1/2 (chemiluminescence/ELISA and Western blot) from 2004 to 2013 were included. Infection rate was expressed as the number of infected individuals per 100,000 inhabitants in a given municipality; municipalities were grouped by microregion for further analysis. A total of 120,192 samples originating from 358 of the 417 municipalities in Bahia (85.8%) were evaluated. The overall HCV coinfection rate in HTLV-positive was 14.31% [2.8 (ranging from 0.4 to 8.0) per 100,000 inhabitants.] Twenty-one (5%) of the municipalities reported at least one case of HTLV/HCV coinfection. Most cases (87%) were concentrated in three microregions (Salvador: 79%, Ilhéus/Itabuna: 5%, Porto Seguro: 3%). Coinfection occurred more frequently in males (51%) with a mean age of 59 [(IQR): 46–59] years. HTLV/HCV coinfection in the state of Bahia was more frequently found among males living in the microregions of Salvador, Ilhéus/Itabuna and Porto Seguro, all of which are known to be endemic for HTLV infection.

Molecular detection of human T cell lymphotropic virus type 1 in pregnant women from Maranhão state, Brazil

The human T cell lymphotropic virus (HTLV) has a worldwide distribution. HTLV is endemic in some states in the northeastern region of Brazil. This study investigated the prevalence of HTLV-1/2 in 713 pregnant women attended at the Central Laboratory of Public Health of Maranhão (LACEN-MA) between February 2015 and May 2017. Serological screening was performed by chemiluminescent microparticle immunoassay (CMIA), and reactive sera were subsequently confirmed by Western blot (WB) analysis. Five samples were determined to be HTLV-1/2-reactive by CMIA analysis, while in the WB analysis, three sera were positive for HTLV-1, and two were indeterminate. The polymerase chain reaction (PCR) analysis used to detect HTLV-1 proviral DNA showed a specific 336 base pair fragment for HTLV-1 in all CMIA-reactive serum samples. PCR products were purified and sequenced. We observed a 0.7% molecular prevalence of HTLV-1 infection. The average age of the HTLV-1-positive pregnant women was 25.6 ± 8.2 years, and the average age of the HTLV-1-negative pregnant women was 24.3 ± 6.2 (p = 0.60). We observed that there was no association of HTLV-1 infection with age, ethnicity, marital status, educational level, family income, age of first sexual intercourse, previous pregnancy, breastfeeding, intravenous drug use by partner, history of blood transfusions, or use of condoms. The prevalence of HTLV-1 observed in pregnant women demonstrated the need to implement public health policies for the screening of HTLV-1/2 in prenatal care and counseling to avoid breastfeeding by infected women; this approach could control vertical transmission and reduce the spread of this virus in the population.

Pregnancy outcomes and mother-to-child transmission rate in HTLV-1/2 infected women attending two public hospitals in the metropolitan area of Rio de Janeiro

HTLV-1/2 are transmitted sexually, by whole cell blood products and from mother-to-child (MTC), mainly through breastfeeding. HTLV-1/2 prevalence in pregnant women is high in Rio de Janeiro, however there were no local studies addressing the rate of adverse pregnancy outcomes (APO) and MTC transmission. The aim was to study sociodemographic characteristics which may be associated to HTLV-1/2 infection and describe pregnancy outcomes and MTC transmission in HTLV-1/2-positive women. The cross-sectional study screened 1,628 pregnant women in of Rio de Janeiro (2012–2014) and found 12 asymptomatic carrier mothers (prevalence = 0.74%). Pregnancy outcome information was retrieved from medical records. Sociodemographic characteristics were similar between the positive and negative groups except for maternal age, which was higher in carrier mothers. The incidence of adverse pregnancy outcomes was similar in infected and non-infected patients (p = 0.33), however there was a high rate of premature rupture of membranes (PROM) amid infected mothers (3/12). Multilevel logistic regression found that for each additional year of age, the chance of being HTLV-1/2-positive increased 11% and that having another sexually transmitted infection (STI) increased 9 times the chance of being infected. Carrier mothers had more antenatal visits (OR = 5.26). Among the children of HTLV-1/2-positive mothers there was one fetal death, one infant death and one loss of follow-up. After two years of follow-up there was one case of MTC transmission (1/9). The mother reported breastfeeding for one month only. Knowledge about factors associated to HTLV-1/2 infection, its impact on pregnancy outcomes and the MTC transmission rate is important to guide public health policies on antenatal screening and management.

HTLV-1/2 are retroviruses transmitted by sex, blood products and from mother to child (MTC), mainly through breastfeeding. There is currently no vaccine, treatment or cure. Although it’s mostly asymptomatic it can cause disabling and even lethal diseases in carriers. The prevalence of HTLV-1/2 in pregnant women at the metropolitan area of Rio de Janeiro is high (0.74%). Our aim was to study the sociodemographic characteristics which may be associated to HTLV-1/2 infection and describe pregnancy outcomes and MTC transmission in the infected population. Apart from being slightly older, there were no differences in the carrier mothers’ sociodemographic profile. Pregnant women with sexually transmitted infections had a 9-fold chance of being HTLV-1/2 positive. Although adverse pregnancy outcomes were not increased, infected mothers had a high rate of ruptured membranes. Among the children of HTLV-1/2-positive mothers there was one fetal death, one infant death and one loss of follow-up. There was one case of MTC transmission (1/9), after one month of breastfeeding. Knowledge about factors associated to HTLV-1/2 infection, its impact on pregnancy, and the MTC transmission rate is important to guide further research and public health policies.

Evidence of New Endemic Clusters of Human T-Cell Leukemia Virus (HTLV) Infection in Bahia, Brazil

Background

Salvador, Bahia (northeastern Brazil), has been identified as the epicenter of Human T-cell leukemia virus Human T-cell leukemia virus (HTLV) type 1 infection in the country. This study aims to estimate the rate of HTLV infection and the geographical distribution of this virus in this state.

Methods

All HTLV tests (chemiluminescence/ELISA assays/Western Blotting) performed in the Central Laboratory of Public Health of Bahia (LACEN) from 2004 to 2013 were included. Data was extracted from LACEN’s database using high volume extract, transformation and load throughput. Infection rate was expressed as the number of infected individuals per 100,000 inhabitants considering municipalities grouped in microregions and/or mesoregions as the unit of analysis.

Results

A total of 233,876 individuals were evaluated. Individuals were from 394 out of 417 municipalities of Bahia (94.5%). HTLV chemiluminescence/ELISA assay was found to be reactive for 3,138 individuals from whom 2,323 had WB results (1,978 positives, 62 negative and 282 indeterminate). Out of 1978 reactive samples, 1,813 (91.7%) were positive for HTLV-1, 58 (2.9%) for HTLV-2 and 107 (5.4%) were for both HTLV-1 and HTLV-2. The cumulative mean rate of HTLV-positive cases in Bahia was 14.4 per 100,000 inhabitants. Three microregions presented rates >20 HTLV-positive cases/100,000 inhabitants: Barreiras (24.83 cases per 100,000 inhabitants), Salvador (22.90 cases per 100,000 inhabitants), and Ilhéus-Itabuna (22.60 cases per 100,000 inhabitants).

Conclusion

HTLV infection is disseminated in the state of Bahia, with an overall moderate rate of infection. Further studies should be conducted to characterize the epidemiological and clinical profile of HTLV-infected individuals better and to propose effective prevention measures.

Mother-to-Child HTLV-1 Transmission: Unmet Research Needs

Mother-to-child transmission (MTCT) of Human T-cell lymphotropic virus type 1 (HTLV-1) causes lifelong infection. At least 5–10 million individuals worldwide are currently living with HTLV-1. Studies of regional variation are required to better understand the contribution of MTCT to the global burden of infection. Although most infected individuals remain asymptomatic ∼10% develop high morbidity, high mortality disease. Infection early in life is associated with a higher risk of disease development. Adult T-cell leukemia (ATL), which is caused by HTLV-1 and has a median survival of 8 months is linked to MTCT, indeed evidence of ATL following infection as an adult is sparse. Infective dermatitis also only occurs following neonatal infection. Whilst HTLV-1-associated myelopathy (HAM) follows sexual and iatrogenic infection approximately 30% of patients presenting with HAM/TSP acquired the infection through their mothers. HAM/TSP is a disabling neurodegenerative disease that greatly impact patient’s quality of life. To date there is no cure for HTLV-1 infection other than bone marrow transplantation for ATL nor any measure to prevent HTLV-1 associated diseases in an infected individual. In this context, prevention of MTCT is expected to contribute disproportionately to reducing both the incidence of HTLV-1 and the burden of HTLV-1 associated diseases. In order to successfully avoid HTLV-1 MTCT, it is important to understand all the variables involved in this route of infection. Questions remain regarding frequency and risk factors for in utero peri-partum transmission whilst little is known about the efficacy of pre-labor cesarean section to reduce these infections. Understanding the contribution of peripartum infection to the burden of disease will be important to gauge the risk-benefit of interventions in this area. Few studies have examined the impact of HTLV-1 infection on fertility or pregnancy outcomes nor the susceptibility of the mother to infection during pregnancy and lactation. Whilst breast-feeding is strongly associated with transmission and avoidance of breast-feeding a proven intervention little is known about the mechanism of transmission from the breast milk to the infant and there have been no clinical trials of antiretroviral therapy (ARV) to prevent this route of transmission.

Estimation of HTLV-1 vertical transmission cases in Brazil per annum

Background

Brazil has at least 800,000 HTLV-1 infected individuals. HTLV-1 can be transmitted via sexual intercourse, contact with blood and from mother to child, mainly by breastfeeding. Treatments for the high morbidity/mortality associated diseases (ATL and HAM/TSP) are limited, therefore, infection prevention is of utmost importance. However, antenatal screening is not routinely performed in Brazil. A lack of data regarding the number of individuals infected via breastfeeding impairs the development of government policies. The objective is to estimate the number of HTLV-1 infections occurring annually due to mother to child transmission (MTCT) in Brazil, nationally and regionally.

Methodology

To estimate HTLV-1 MTCT in Brazil the following variables are modelled: number of births, prevalence of HTLV-1 infection in pregnant women, breastfeeding duration rate and transmission risk according to breastfeeding period. The number of cases of HAM/TSP and ATL attributable to MTCT are also estimated.

Principal findings

In 2008, there were 2,934,828 live births in Brazil. HTLV prevalence in pregnant women in Brazil ranges between 0.1–1.05% by region. An estimated 16,548 HTLV-1 infected women are pregnant each year. According to the breastfeeding pattern and HTLV-1 prevalence of each region there are an estimated 3,024 new cases of HTLV-1 infection due to MTCT annually of which 2,610 are preventable through infant feeding advice. These 3,024 transmissions will result in 120–604 cases of ATL and 8–272 of HAM/TSP. North-East region comprises the high number of MTCT cases, followed by South-East.

Conclusions/significance

A high number of new HTLV-1 infections due to MTCT occur every year in Brazil. Antenatal screening and avoiding breastfeeding are essential to prevent subsequent development of HTLV-1-associated diseases.

The human T-cell lymphotropic virus type 1 (HTLV-1) causes lifelong infection in humans. Although most infected individuals remain asymptomatic HTLV-1 causes severe disease in at least 5% of carriers. In the present study we estimate the number of HTLV-1 infections that occur annually due to mother to child transmission (MTCT) in Brazil and within its regions. The high number of estimated cases due to MTCT (3,024) which will give rise in adult life to HTLV-1associated diseases suggest the importance of performing HTLV-1 antenatal screening in Brazil to reduce the dissemination of this infection and to thus prevent a blood cancer to which most individuals succumb within 8 months of presentation and in others a disabling disease of the spinal cord.

HTLV-1 is predominantly sexually transmitted in Salvador, the city with the highest HTLV-1 prevalence in Brazil

Background

Salvador is the city with the highest number of HTLV-1 infected individuals in Brazil, yet the main route of HTLV-1 transmission is unknown.

Objective

To investigate the association of syphilis infection as a proxy for sexual transmission of HTLV-1 infection in the general population of this city.

Methods

A cross sectional population-based study was conducted with 3,451 serum samples obtained by a representative simple random sampling. Data on gender, age, income, and years of education were collected by questionnaire and the presence of HTLV, HIV and Treponema pallidum infection was determined by serology. Logistic regression analysis was used to evaluate the independent effect of the potential explanatory variables to HTLV-1 infection and Odds Ratios (OR) and 95% CI were calculated.

Results

The majority of studied individuals were female (56.4%), had less than 7 years of education (55.3%) and earned two or less minimum wages (52.0%). The overall prevalence of HTLV-1 was 1.48% (51/3,451; 95% CI: 1.10%– 1.94%), which increased with age. Only three persons younger than 17 (3/958; 0.31%; CI 95% 0.06–0.91) years were infected by HTLV-1. Among the 45 syphilis positives, 12 (26.7%) were HTLV positive, while among 21 HIV positives, only one (4.8%) was HTLV positive. HTLV-1 infection was found to be associated with syphilis infection (OR_ADJUSTED 36.77; 95% CI 14.96–90.41).

Conclusion

The data presented herein indicate that horizontal transmission between adults is the main route of HTLV-1 infection in the general population of Salvador and that this is likely to occur through sexual contact.

Tuberculosis incidence in a cohort of individuals infected with human T-lymphotropic virus type 1 (HTLV-1) in Salvador, Brazil

Background

Few reports have investigated the association between human T-lymphotropic virus type 1 (HTLV-1) and tuberculosis (TB) in countries where both infections are endemic. This study estimates the incidence of TB in a cohort infected with HTLV-1, compared with non-infected individuals, over a ten-year period.

Methods

Retrospective cohort study involving the cross-matching of records of individuals for whom a HTLV serology was performed at a referral center for HTLV (CHTLV) with a database of TB cases from Sinan—the Information System on Diseases of Compulsory Declaration between 2002 and 2012.

Results

From a cohort of 6,495 individuals, 1,711 were infected with HTLV-1. A total of 73 TB cases occurred during the study period: 33 HTLV-1-infected patients and 40 uninfected individuals. The incidence density for TB in the HTLV-1 infected group was 3.3 person-years per 1,000 individuals and 1.1 person-years per 1,000 individuals in the group HTLV-1 uninfected group. The relative risk of developing TB in the group of patients infected with HTLV-1 was 2.6 (CI 95 % 1.6–4.2) in comparison with HTLV-1 uninfected group. Compared to individuals with isolated TB, those in the HTLV-1 infected group who had TB were older (p = 0.005) and had lower education levels (p = 0.02). No differences were observed with respect to the clinical/radiological presentation, nor in the outcome of TB and prevalence of HIV infection, when comparing among the HTLV-1-infected and uninfected groups.

Conclusions

Patients infected with HTLV-1 are more susceptible to TB. The epidemiological characteristics of HTLV-1/TB subjects and those infected with TB overlap.

Dried blood spot testing for the antenatal screening of HTLV, HIV, syphilis, toxoplasmosis and hepatitis B and C: prevalence, accuracy and operational aspects

INTRODUCTION

Screening for vertically transmitted infection is mandatory and must be conducted at the first prenatal consultation. The most vulnerable women's groups are those at the lowest socio-economic level. Dried blood spot testing on filter paper could represent a secure way to screen pregnant women in the prenatal period.

METHODS

A cross-sectional study was conducted between November 2009 and March 2010, in the Metropolitan Region of Salvador, Bahia, Brazil, to compare the accuracy of the dried blood spot in filter paper and venipuncture serological as screening methods for HIV, HTLV, VHB, VHC, Treponema pallidum, and Toxoplasma gondii during prenatal period. Results of the venous blood sample collected in tubes were considered the gold standard.

RESULTS

Serum samples and dried blood spot were obtained from 692 pregnant women aged between 14 and 42 years, with a median age of 26. Thirteen women were seropositive for T. gondii (1.88%; 95% CI: 0.60-2.71%), five for T. pallidum (0.72%; 95% CI: 0.15-1.61%), two for HBV (0.29%; 95% CI: 0.050.95%) and one for HTLV-1 (0.14%; 95% CI: 0.01-0.71%). No one was positive for HCV and HIV. The dried blood spot accuracy for syphilis and HTLV were 100% (95% CI: 99.25-100) and 100% (95% CI: 99.45-100%), respectively. The average time between blood collection and recording of the sample in the reference laboratory was 4.93 (3.82) days and between dried blood spot processing and active search for pregnant women was 3.44 (4.27) days.

CONCLUSIONS

The use of dried blood spot may represent a secure way to expedite access to results of vertically transmitted diseases in the prenatal period, particularly in regions with scarce healthcare resources.

Prevalence of HTLV-1/2 in pregnant women living in the metropolitan area of Rio de Janeiro

Background

HTLV-1/2 infection can cause severe and disabling diseases in children and adults. The aim of the study was to estimate the prevalence of HTLV-1/2 infection in pregnant women living in the metropolitan area of Rio de Janeiro.

Methodology/Principal Findings

1,204 pregnant women were tested upon hospital admission for delivery in two public hospitals in the cities of Rio de Janeiro and Mesquita, between November, 2012 and April, 2013. The samples were screened by chemiluminescent microparticle immunoassay (CMIA) and reactive ones were confirmed by Western blot (WB). Epi-info software was used for building the database and performing the statistical analysis. Eight patients had confirmed HTLV-1/2 infection (7 HTLV-1, one HTLV-2), equivalent to a prevalence rate of 0.66%. Two further reactive screening tests had negative Western blot results and therefore were considered negative in the statistical analysis. All HTLV-1/2-positive patients were born in Rio de Janeiro, most were non-Caucasian (87.5%), in a stable relationship (62.5%), had at least ten years of formal education (62.5%) and a monthly family income of up to US$600.00 (87.5%). There was only one case of coinfection with syphilis and none with HIV. The mean age of the infected women was 28.4 (SD = 6.3) years and of the seronegative ones was 24.8 (SD = 6.5) (p = 0.10). The median number of pregnancies were 3.0 and 1.0 (p = 0.06) and the median number of sexual partners were 3.5 and 3.0 (p = 0.33) in the seropositive and negative groups, respectively. There were no statistically significant differences between the groups.

Conclusions/Significance

A significant prevalence of HTLV-1/2 was found in our population. The socio-epidemiological profile of carrier mothers was similar to the controls. Such findings expose the need for a public health policy of routine HTLV-1/2 screening in antenatal care, since counselling and preventive measures are the only strategies currently available to interrupt the chain of transmission and the future development of HTLV-1/2-related diseases.

HTLV-1/2 are retroviruses transmitted by blood products, sexual contact and from mother to child, mainly through breastfeeding. The infection has a characteristic geographical distribution with endemic areas often neighbouring very low prevalence areas. Infection is life long and although asymptomatic in most cases, it can cause severe and disabling diseases in children and adults. There is currently no cure, vaccine or effective treatment for HTLV-1/2 infections. Our research is the first to study the prevalence of HTLV-1/2 in pregnant women living in the metropolitan area of Rio de Janeiro, the second largest in Brazil. 1,204 pregnant women were tested upon hospital admission for delivery in two public hospitals in the cities of Rio de Janeiro and Mesquita, between November, 2012 and April, 2013 and a significant prevalence of HTLV-1/2 was found (0.66%). The socio-epidemiological profile of carrier mothers was similar to the controls'. Epidemiological knowledge is fundamental for the elaboration of public health policies such as routine HTLV-1/2 screening in antenatal care, since counselling and preventive measures, mainly avoidance of breastfeeding, are the only strategies currently available to interrupt the chain of transmission and the future development of HTLV-1/2-related diseases.

HTLV-1 in pregnant women from the Southern Bahia, Brazil: a neglected condition despite the high prevalence

BACKGROUND

As the most frequent pathway of vertical transmission of HTLV-1 is breast-feeding, and considering the higher prevalence in women, it is very important to perform screening examinations for anti-HTLV-1 antibodies as part of routine prenatal care. So far, no studies of HTLV-1 seroprevalence in pregnant women in the Southern region of Bahia, Brazil, have been described.

METHODS

Pregnant women were selected at the two regional reference centers for health care from Southern Bahia. A total of 2766 pregnant women attending the antenatal unit between November 2008 and May 2010 have been analyzed. An extra blood sample was drawn during their routine antenatal testing. A standardized questionnaire was applied and all positive plasma samples were tested by ELISA and were confirmed by Western Blot and PCR. Besides that, positive women were contacted and visited. The family members that were present during the visit were asked to be serologically screened to the virus. A prospective study was also carried out and newborns were followed up to two years for evaluation of vertical transmission.

RESULTS

HTLV prevalence was 1.05% (CI 95%: 0.70-1.50). There was no association of HTLV-1 infection with age, education, income and ethnic differences. The association with marital status was borderline (OR = 7.99; 95% CI 1.07-59.3; p = 0.042). In addition, 43 family members of the HTLV-1 seropositive women have been analyzed and specific reactivity was observed in 32.56%, including two children from previous pregnancy.

CONCLUSION

It is very important to emphasize that the lack of HTLV-1 screening in pregnant women can promote HTLV transmission especially in endemic areas. HTLV screening in this vulnerable population and the promotion of bottle-feeding for children of seropositive mothers could be important cost-effective methods to limit the vertical transmission. Besides that, our data reinforce the need to establish strategies of active surveillance in household and family contacts as important epidemiological surveillance actions for the early detection of virus infection and the prevention of transmission by sexual or and parenteral contact.

High prevalence of human T-lymphotropic virus infection in indigenous women from the peruvian Amazon

Background

In an earlier study, we detected an association between human T-cell lymphotropic virus (HTLV) infection and cervical human papillomavirus (HPV) in indigenous Amazonian Peruvian women of the Shipibo-Konibo ethnic group. As both HTLV and HPV can be transmitted sexually, we now report a population-based study examining the prevalence and risk factors for HTLV-1 and HTLV-2 infection in this population.

Methods

Between July and December 2010, we conducted a comprehensive screening for HTLV among Shipibo-Konibo women 15 to 39 years of age living in two communities located in Lima and in 17 communities located within four hours by car or boat from the Amazonian city of Pucallpa in Peru.

Results

We screened 1,253 Shipibo-Konibo women for HTLV infection 74 (5.9%) tested positive for HTLV-1, 47 (3.8%) for HTLV-2 infection, and 4 (0.3%) had indeterminate results. In the multivariate analysis, factors associated with HTLV-1 infection included: older age (Prevalence Ratio (PR): 1.04, 95% CI 1.00–1.08), primary education or less (PR: 2.01, 95% CI: 1.25–3.24), younger or same age most recent sex partner (PR: 1.66, 95% CI: 1.00–2.74), and having a most recent sex partner who worked at a logging camp (PR: 1.73, 95% CI: 1.09–2.75). The only factor associated with HTLV-2 infection was older age (PR: 1.08, 95% CI: 1.03–1.12).

Conclusion

HTLV infection is endemic among Shipibo-Konibo women. Two characteristics of the sexual partner (younger age and labor history) were associated with infection in women. These results suggest the need for implementation of both HTLV screening during the antenatal healthcare visits of Shipibo-Konibo women, and counseling about the risk of HTLV transmission through prolonged breastfeeding in infected women. We also recommend the implementation of prevention programs to reduce sexual transmission of these viruses.

Epidemiological Aspects and World Distribution of HTLV-1 Infection

The human T-cell leukemia virus type 1 (HTLV-1), identified as the first human oncogenic retrovirus 30 years ago, is not an ubiquitous virus. HTLV-1 is present throughout the world, with clusters of high endemicity located often nearby areas where the virus is nearly absent. The main HTLV-1 highly endemic regions are the Southwestern part of Japan, sub-Saharan Africa and South America, the Caribbean area, and foci in Middle East and Australo-Melanesia. The origin of this puzzling geographical or rather ethnic repartition is probably linked to a founder effect in some groups with the persistence of a high viral transmission rate. Despite different socio-economic and cultural environments, the HTLV-1 prevalence increases gradually with age, especially among women in all highly endemic areas. The three modes of HTLV-1 transmission are mother to child, sexual transmission, and transmission with contaminated blood products. Twenty years ago, de Thé and Bomford estimated the total number of HTLV-1 carriers to be 10-20 millions people. At that time, large regions had not been investigated, few population-based studies were available and the assays used for HTLV-1 serology were not enough specific. Despite the fact that there is still a lot of data lacking in large areas of the world and that most of the HTLV-1 studies concern only blood donors, pregnant women, or different selected patients or high-risk groups, we shall try based on the most recent data, to revisit the world distribution and the estimates of the number of HTLV-1 infected persons. Our best estimates range from 5-10 millions HTLV-1 infected individuals. However, these results were based on only approximately 1.5 billion of individuals originating from known HTLV-1 endemic areas with reliable available epidemiological data. Correct estimates in other highly populated regions, such as China, India, the Maghreb, and East Africa, is currently not possible, thus, the current number of HTLV-1 carriers is very probably much higher.

HTLV-1/2 seroprevalence and coinfection rate in Brazilian first-time blood donors: an 11-year follow-up

The seroprevalence and geographic distribution of HTLV-1/2 among blood donors are extremely important to transfusion services. We evaluated the seroprevalence of HTLV-1/2 infection among first-time blood donor candidates in Ribeirão Preto city and region. From January 2000 to December 2010, 1,038,489 blood donations were obtained and 301,470 were first-time blood donations. All samples were screened with serological tests for HTLV-1/2 using enzyme immunoassay (EIA). In addition, the frequency of coinfection with hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), Chagas disease (CD) and syphilis was also determined. In-house PCR was used as confirmatory test for HTLV-1/2. A total of 296 (0.1%) first-time donors were serologically reactive for HTLV-1/2. Confirmatory PCR of 63 samples showed that 28 were HTLV-1 positive, 13 HTLV-2 positive, 19 negative and three indeterminate. Regarding HTLV coinfection rates, the most prevalent was with HBV (51.3%) and HCV (35.9%), but coinfection with HIV, CD and syphilis was also detected. The real number of HTLV-infected individual and coinfection rate in the population is underestimated and epidemiological studies like ours are very informative.

Descriptive study of HTLV infection in a population of pregnant women from the state of Pará, Northern Brazil

INTRODUCTION

In Brazil, studies have shown that HTLV seroprevalence among pregnant women varies from 0 to 1.8%. However, this seroprevalence was unknown in the State of Pará, Brazil. The present study describes, for the first time, the HTLV seroprevalence among pregnant women from the State of Pará, Northern Brazil.

METHODS

13,382 pregnant women were submitted to HTLV screening during prenatal care, and those with non-seronegative results to anti-HTLV were submitted to Western blot (WB) test to confirm and separate HTLV-1 and HTLV-2 carriers.

RESULTS

HTLV seroprevalence in the population of pregnant women was 0.3%, and HTLV-1 was identified in 95.3% of patients. The demographic profile of HTLV carriers was as follows: women with age between 20 and 40 years old (78.4%); residing in the metropolitan region of Belém, Pará (67.6%); and with educational level of high school (56.8%). Other variables related to infection were as follows: beginning of sexual intercourse between the age of 12 and 18 years old (64.9%) and have being breastfed for more than 6 months (51.4%). Most of the women studied had at least two previous pregnancies (35.1%) and no abortion (70.3%). Coinfections (syphilis and HIV) were found in 10.8% (4/37) of these pregnant women.

CONCLUSIONS

Seroprevalence of HTLV infection in pregnant women assisted in basic health units from the State of Pará, Northern Brazil, was 0.3% similar to those described in other Brazilian studies. The variables related to infection were important indicators in identifying pregnant women with a higher tendency to HTLV seropositivity, being a strategy for disease control and prevention, avoiding vertical transmission.

HTLV infection and its implication in gynaecology and obstetrics

INTRODUCTION

Worldwide, 20-30 million people are estimated to be infected with HTLV. HTLV-1 is endemic in Western Africa and Southern Japan, whereas HTLV-2 is considered to be spread among native American people.

MATERIALS AND METHODS

The impact of HTLV in gynaecology and obstetrics is being reviewed. Search strategy and selection criteria for identifying relevant data were performed by searching Medline, Current Contents, Web of Science, Embase and references from relevant articles. English and German gynaecological and infectious diseases textbooks as well as national and international guidelines and recommendations were also reviewed.

RESULTS

Transmission may occur by sexual intercourse or cellular blood products. Although materno-fetal transmission is debated, transmission through maternal breast milk has been confirmed. An HTLV-infection can lead to adult T-cell leukaemia (ATL) or cumulative opportunistic and neurological disorders that can occur with varying degrees of severity. Diagnosis can be done by antibody detection via the use of ELISA and western blot analysis as well as PCR diagnosis.

CONCLUSION

Due to inadequate treatment options and the lack of an effective vaccination, prevention is currently only possible by restricting transmission, including the usage of condoms during sexual intercourse or avoiding breastfeeding in HTLV-seropositive mothers. If, due to socio-economic reasons, breastfeeding cannot be avoided, short-term breastfeeding for a maximum of up to 6 months is suggested.

Prevalence and risk factors for HIV, syphilis, hepatitis B, hepatitis C, and HTLV-I/II infection in low-income postpartum and pregnant women in Greater Metropolitan Vitória, Espírito Santo State, Brazil

Sexually transmitted infections during pregnancy pose a major risk to the fetus due to vertical transmission. The study's objective was to determine the prevalence of HIV, syphilis, hepatitis B and C, and HTLV-I/II infection among low-income postpartum and pregnant women treated in Greater Metropolitan Vitória, Espírito Santo State, Brazil, and the risk factors associated with these infections. A cross-sectional study was conducted from February to October 1999 assessing postpartum and pregnant women from the maternity ward of the Vitória Mercy Hospital and the Carapina Outpatient Referral Unit in the Municipality of Serra, respectively. Patients were systematically interviewed and had blood samples drawn for serological tests (HIV 1&2, VDRL, HbsAg, anti-HCV, and HTLV-I/II). A total of 534 patients (332 postpartum and 202 pregnant women) were assessed. Seroprevalence rates for the target infections in postpartum and pregnant women and the overall sample were as follows, respectively: HIV 0.9%, 0%, and 0.6%; syphilis 2.1%, 3.6%, and 2.7%; HBV 1.2%, 1%, and 1.1%; HCV 1.8%, 0.6%, and 1.4%; and HTLV-I/II 1.7%, 0.6%, and 1.3%. Factors associated with the various infections are presented and analyzed in light of other research findings from the literature.

[Prevalence of human T-cell lymphotropic virus (HTLV-1/2) infection among puerperae in Cuiabá, Mato Grosso, 2006]

The prevalence of human T-cell lymphotropic virus (HTLV-1/2) infection among puerperae in the State of Mato Grosso, Brazil, is unknown. Through this cross-sectional study, the prevalence of HTLV-1/2 infection among puerperae attended at three public maternity hospitals in Cuiabá, State of Mato Grosso, was defined. Between April and September 2006, 3,831 deliveries took place and 2,965 puerperae underwent serological tests for HTLV-1/2: enzyme-linked immunosorbent assay (ELISA) and western blot. The mean age of the women studied was 23.9 years. The prevalence of HTLV-1/2 was 0.2%, i.e. similar to the prevalence observed in the general population of many developed centers in Brazil. This finding of low prevalence suggests that there is still no justification for introducing public health interventions for the population of pregnant women in our setting, to reduce the vertical transmission of HTLV-1/2.

[HTLV 1/2 infection: prenatal performance as a disease control strategy in State of Mato Grosso do Sul]

In this study, the prevalence of HTLV 1/2 infection among pregnant women in the State of Mato Grosso do Sul was estimated by means of the ELISA, Western Blot and PCR techniques, in blood samples collected by peripheral venous puncture. 116,689 pregnant women were examined and 153 were diagnosed as presenting HTLV 1/2 infection, with prevalence of 0.13%. Among these 153 pregnant women, 133 (86.9%) had type 1 and 20 (11.1%) had type 2; 73.2% were black, brown or indigenous; about 90% performed domestic activities; and 75.8% (116/153) had been to school for seven years or less. The 153 pregnant women had 172 pregnancies during the study period and 164 pregnancies were followed. Out of pregnancies that were followed, 6.7% (11/164) evolved to abortion, 26.8% (41/153) reported previous abortions and 31.7% (13/41) had had more than two abortions. Comorbidities were found in 17% (26/153), among whom 3.3% (5/153) had HIV (p<0.000002). The authors emphasize the importance of identifying pregnant women with HTLV 1/2 infection, as a strategy for disease control and prevention.

Phylogenetic and molecular analysis of HTLV-1 isolates from a medium sized town in northern of Brazil: tracing a common origin of the virus from the most endemic city in the country

Salvador-Bahia has the highest prevalence of HTLV-1 infection in Brazil; about 2% of the population is infected. In this city, the prevalence of HTLV in pregnant women is 1%. There is no data of the HTLV-1 prevalence in others cities of the Bahia's Recôncavo, where the population has similar social and demography characteristics to those from Salvador. Our aim was to evaluate the seroprevalence of HTLV in pregnant women in Cruz das Almas-Bahia, a medium-sized city from the Bahia's Recôncavo. All individuals were tested for HTLV (ELISA) and the positive samples were confirmed by Western Blot. Phylogenetic analyses of the total LTR region were performed in all positive samples. We tested 408 samples (45.4% of the estimate pregnant women population) between June 1st and October 31, 2005. The prevalence of HTLV-1 infection was 0.98%. In addition, all isolated virus were grouped in the subtype HTLV-1a, in the Latin American group. Our results suggest that the introduction of HTLV-1 occurred after the slave trade into Salvador. In addition, HTLV-1-infection should be screened during the pregnancy in women originating from HTLV-1 endemic areas.

Retrospective study of the prevalence of human T-cell lymphotropic virus-type 1/2, HIV, and HBV in pregnant women in Argentina

This study shows first data on HTLV-1/2 seroprevalence among pregnant women in the non-endemic region of Argentina. In a retrospective study a representative sample (n = 3,143) of the pregnant women registered in the health public service in the province of Córdoba was evaluated. HTLV-1/2 seroprevalence was 0.191% +/- 0.0857 [IC 0.022-0.359]. This prevalence was 10 times higher in pregnant women than in blood donors [0.019 (4/21.183)]. The pregnant women would reflect the epidemiology of the general population more accurately since it constitutes a more heterogeneous group than that of blood donors. The prevalence of infection with HIV was 2.8 times higher than that of HTLV-1/2 (P < 0.05) and the presence of any of these two viruses was not a subrogating indicator of the presence of the other (Goodman and Kruskal's Tau coefficient = 0.0092). The prevalence of HBV was not significantly different from that of HTLV-1/2 (P > 0.05). We consider that it is necessary to carry out continuous studies in order to define the main risk factors for infection of these women. Thus, a decision could be made to apply the best policy in public health to prevent vertical transmission of the virus in Argentina.

[Frequency of HIV-1, rubella, syphilis, toxoplasmosis, cytomegalovirus, simple herpes virus, hepatitis B, hepatitis C, Chagas disease and HTLV I/II infection in pregnant women of State of Mato Grosso do Sul]

It was aimed to estimate the frequency of syphilis, rubella, hepatitis B, hepatitis C, toxoplasmosis, Chagas disease, HTLV I/II, simple herpes virus, HIV-1 and cytomegalovirus in pregnant women and to evaluate the relationship between age and the frequency of the infections studied. A transversal study of 32,512 pregnant women submitted to pre-natal screening in the period of November 2002 to October 2003. The frequency of the tried infections among the pregnant women were 0.2% of HIV-1, 0.03% of rubella, 0.8% of syphilis, 0.4% of toxoplasmosis, 0.05% of cytomegalovirus, 0.02% of simple herpes virus, 0.3% of HBsAg, 0.1% of hepatitis C, 0.1% of HTLV and 0.1% of Chagas disease. There was significative statistical association between age and prenatal infection of rubella, cytomegalovirus, Chagas disease and herpes virus. The rates of frequency of rubella, syphilis, toxoplasmosis, Chagas disease and cytomegalovirus in pregnant women studied were lower than the compared rates.

Human T-lymphotropic virus 1: recent knowledge about an ancient infection

Human T-lymphotropic virus 1 (HTLV-1) has infected human beings for thousands of years, but knowledge about the infection and its pathogenesis is only recently emerging. The virus can be transmitted from mother to child, through sexual contact, and through contaminated blood products. There are areas in Japan, sub-Saharan Africa, the Caribbean, and South America where more than 1% of the general population is infected. Although the majority of HTLV-1 carriers remain asymptomatic, the virus is associated with severe diseases that can be subdivided into three categories: neoplastic diseases (adult T-cell leukaemia/lymphoma), inflammatory syndromes (HTLV-1-associated myelopathy/tropical spastic paraparesis and uveitis among others), and opportunistic infections (including Strongyloides stercoralis hyperinfection and others). The understanding of the interaction between virus and host response has improved markedly, but there are still no clear surrogate markers for prognosis and there are few treatment options.

High endemicity of human T-cell lymphotropic virus type 1 among pregnant women in peru

Human T-cell lymphotropic virus type 1(HTLV-1) is associated with adult T-cell leukemia, tropical spastic paraparesis, and other immune-mediated diseases. There are reports of groups with high prevalences of HTLV-1 infection in Peru, but there is limited knowledge of the epidemiology of infection or which routes of infection are most important. We studied 2,492 women presenting to a large maternity hospital in Lima for prenatal, delivery, or abortion services. HTLV-1 seropositivity was confirmed in 42 women (1.7%; 95% confidence interval, 1.2-2.2). Seroprevalence increased with age but did not vary by region of birth or recency of migration to Lima. Age greater than 30 years and sexual intercourse before 20 years of age were strongly and independently associated with infection. History of abortion and history of transfusion were of borderline significance. Women whose male partner had a characteristic that might be a marker for risk of sexually transmitted infections were also more likely to be infected. HTLV-1 is common among Peruvians throughout the country and is maintained by a low level of neonatally acquired infection that is amplified by sexual transmission. In addition to screening of the blood supply, instituted in 1997, programs designed to reduce neonatal and sexual transmission should be effective.

Global epidemiology of HTLV-I infection and associated diseases

Epidemiologic aspects of human T-lymphotropic virus type I (HTLV-I) infection have been thoroughly studied over the course of approximately 25 years since its first description. The geographic distribution of the virus has been defined, with Japan, Africa, Caribbean islands and South America emerging as the areas of highest prevalence. The reasons for HTLV-I clustering, such as the high ubiquity in southwestern Japan but low prevalence in neighboring regions of Korea, China and eastern Russia are still unknown. The major modes of transmission are well understood, although better quantitative data on the incidence of transmission, and on promoting/inhibiting factors, are needed. Epidemiologic proof has been obtained for HTLV-I's causative role in major disease associations: adult T-cell leukemia (ATL), HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), HTLV-associated uveitis and infective dermatitis. However, more and better studies are needed for other apparent disease outcomes such as rheumatologic, psychiatric and infectious diseases. Since curative treatment of ATL and HAM/TSP is lacking and a vaccine is unavailable, the social and financial cost for the individual, his/her family and the health system is immense. For this reason, public health interventions aimed at counseling and educating high-risk individuals and populations are of paramount importance.

Infective Dermatitis and Human T Cell Lymphotropic Virus Type 1-Associated Myelopathy/Tropical Spastic Paraparesis in Childhood and Adolescence

BACKGROUND

Human T cell lymphotropic virus type 1 (HTLV-1)-associated infective dermatitis (IDH) is a chronic and recurrent eczema occurring during childhood and adolescence. HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a chronic myelopathy of adulthood, presenting with slowly progressive spastic paraparesis and sphincter dysfunction with mild sensory involvement. There are few reports describing an association between IDH and HAM/TSP. The objective of this study was to evaluate the occurrence of HAM/TSP in patients with IDH and in seropositive members of their families and to determine the blood levels of antibodies against HTLV-1 in patients with HAM/TSP.

METHODS

Twenty patients with IDH and their seropositive mothers and siblings underwent clinical, neurological, and laboratory evaluations. The diagnosis of HAM/TSP was made in accordance with the World Health Organization criteria.

RESULTS

Nine individuals had HAM/TSP (6 of the patients with IDH, 2 mothers, and 1 seropositive brother). In 3 families, > 1 individual had HAM/TSP. The serum antibody titers of the patients with HAM/TSP varied from 1 : 3.125 to 1 : 78.125.

CONCLUSIONS

A strong association was observed between IDH and HAM/TSP. The familial clustering of both diseases suggests a genetic background. Serological screening for HTLV-1 in children with symptoms of myelopathy is essential in areas where HTLV-1 is endemic.

Infective dermatitis associated with the human T cell lymphotropic virus type I in Salvador, Bahia, Brazil

BACKGROUND

Infective dermatitis associated with human T cell lymphotropic virus type I (HTLV-I) infection is a chronic, relapsing eczema of childhood.

METHODS

Children, their mothers, and their siblings underwent serological testing for HTLV-I. Epidemiological data were collected from all seropositive children and their family members, and clinical and dermatological examinations were performed. Laboratory studies, including skin culture, and histopathological analyses were also performed. The diagnosis of infective dermatitis associated with HTLV-I (IDH) was made according to previously established criteria.

RESULTS

All of the patients with cases that demonstrated clinical aspects of IDH were positive for HTLV-I. The median age of the children at the time of the first visit was 8.0 years (range, 2-14 years). The median duration of breastfeeding for 19 children was 22.5 months (range, 1-48 months). The lesions were erythematous, scaly, exudative, and crusted in all cases. The scalp, retroauricular areas, neck, and groin were the regions that were commonly affected. Cultures were positive for Staphylococcus aureus for 95% of the patients. The children were followed-up for a median of 3.0 years (range, 0.1-7 years), and 5 children developed HTLV-I-associated myelopathy/tropical spastic paraparesis. All of the children except 1 were treated with sulfamethoxazole-trimethoprim, and their lesions either improved greatly or completely disappeared.

CONCLUSIONS

The present study demonstrates the severity of IDH in Bahia and confirms that its diagnosis is based almost exclusively on clinical aspects of the disease. Serological testing for HTLV-I and careful follow-up is recommended for all children with chronic, relapsing, severe eczema in regions where HTLV-I is endemic.

[HTLV1 infection and pregnancy]

OBJECTIVE

We report an epidemiological study with an analysis of the risk factors of the HTLV-1 seroprevalence in pregnant women and their children in the town of St Laurent du Maroni, French Guyana.

MATERIAL AND METHOD

HTLV-1 seroprevalence and risk associated factors were first studied in all the pregnant women having delivered at St. Laurent between July 1991 and June 1993. Then, a retrospective analysis was performed in the children, aged between 18 months and 12 years old, born from HTLV-1 infected mothers, focusing especially on the duration of breast feeding and the level of HTLV-1 anti body titers and proviral load.

RESULTS

The global HTLV-1 seroprevalence was 4.4% (75/1727) but it was more prevalent among ethnic groups of African origin such as the Noir Marron population (5.5%) and Haitians (6.3%). In the Noir-Marron population, which represents 70% of the studied population, HTLV-1 seropositivity was associated with a maternal age of>35 years, prior miscarriage, prior cesarean section, parity>4, gravidity>6 and negative rhesus factor. After logistic regression, HTLV-1 seropositivity remained associated with gravidity>6 and negative rhesus factor. Out of the 216 children born from 81 HTLV-1 infected mothers, only 21 were found to be HTLV-1 seropositive, giving a crude HTLV-1 transmission rate of 9.7% while among the 180 breast-fed children 10.6% were HTLV-1 seropositive. HTLV-1 seropositivity in children was associated with elevated maternal anti HTLV-1 antibody titer, high maternal HTLV-1 proviral load and child's gender, girls being more frequently HTLV-1 infected than boys.

CONCLUSION

HTLV-1 infection, which can be responsible for severe pathologies in adults (adult T cell leukemia and tropical spastic paraparesis/HTLV-1 associated myelopathy) should be screened during pregnancy in women originating from high HTLV-1 endemic areas, as for France, mainly the French West Indies, French Guyana and Intertropical Africa. In case of HTLV-1 seropositivity, mothers should be informed on the risk of transmission and promotion of bottle feeding of their children should be strongly proposed.

HTLV-I in the general population of Salvador, Brazil: a city with African ethnic and sociodemographic characteristics

The city of Salvador has the highest prevalence of HTLV-I among blood donors in Brazil. To study the prevalence of HTLV-I among the general population of Salvador, 30 "sentinel surveillance areas" were selected for the investigation of various infectious diseases, and 1385 individuals within these areas were surveyed according to a simple random sample procedure. ELISA was used to screen plasma samples for antibodies to HTLV-I, and the positive samples were tested by a confirmatory assay (Western blotting). The overall prevalence of HTLV-I was 1.76% (23/1385). Infection rates were 1.2% for males and 2.0% for females. Specific prevalence demonstrated an increasing linear trend with age. No one younger than 13 years of age was infected. Multivariate analysis estimated adjusted odds ratios for the association of HTLV-I with age of 9.7 (3.3; 30.4) for females and 12.3 (1.47; 103.1) for males. Less education and income might be associated with HTLV-I infection in females. Phylogenetic analysis of the long terminal repeat fragments showed that most of the samples belonged to the Latin American cluster of the Transcontinental subgroup (Cosmopolitan subtype). For the entire city of Salvador, it is estimated that approximately 40000 individuals are infected with HTLV-I. Our results suggest multiple post-Colombian introductions of African HTLV-Ia strains in Salvador.

Prevalência da infecção pelo vírus linfotrópico humano de células T e fatores de risco associados à soropositividade em doadores de sangue da cidade de Rio Branco, AC, Brasil (1998-2001)

Para cada doador de sangue soropositivo (ELISA, Abbott®) para HTLV-I/II, de dezembro de 1998 a março de 2001, também foram selecionados dois soronegativos. As amostras séricas foram re-testadas pelo ELISA (Murex®) e aquelas que permaneceram soropositivas foram testadas pelo Western Blot e pela PCR. Das 11.121 amostras séricas, 73 (0,66%) foram positivas (Abbott®), mas somente 12 (0,11%) permaneceram positivas (Murex®), enquanto que as 146 soronegativas foram confirmadas, apesar de ser sofrível o índice de concordância entre os dois ELISA. O Western Blot confirmou as 12 amostras como soropositivas: 8 (0,07%) HTLV-I; duas (0,02%) HTLV-II e duas (0,02%) indeterminadas - sendo pela PCR uma pelo HTLV-I e a outra pelo HTLV-II. Em conclusão, nessa população da Amazônia Ocidental foi muito baixa a soroprevalência de HTLV-I/II, apesar de ser esperada maior prevalência do HTLV-II devido a grande miscigenação racial indígena.

Globin haplotypes of human T-cell lymphotropic virus type I-infected individuals in Salvador, Bahia, Brazil, suggest a post-Columbian African origin of this virus

The city of Salvador, Bahia, Brazil, has sociodemographic characteristics similar to some African cities. Up to now, it has had the highest prevalence of human T-cell lymphotropic virus type I (HTLV-I) infection (1.74%) in the country. To investigate which strains of HTLV-I are circulating in Salvador, we studied isolates from 82 patients infected with HTLV-I: 19 from the general population, 21 from pregnant women, 16 from intravenous drug users, and 26 from patients and their family attending a neurologic clinic. Phylogenetic analysis from part of the LTR fragments showed that most of these isolates belonged to the Transcontinental subgroup of the Cosmopolitan subtype (HTLV-Ia). Only one sample from a pregnant woman was closely related to the Japanese subgroup, suggesting recent introduction of a Japanese HTLV-I lineage into Salvador. betaA-Globin haplotypes were examined in 34 infected individuals and found to be atypical, confirming the racial heterogeneity of this population. A total of 20 chromosomes were characterized as Central African Republic (CAR) haplotype (29.4%), 31 (45.6%) were characterized as Benin (BEN) haplotype, and 17 (25%) were characterized as Senegal (SEN) haplotype. Five patients' genotypes (14.7%) were CAR/CAR; 10 (29,4%), BEN/BEN; 9 (26.5%), CAR/BEN; 2 (5.9%), BEN/SEN; and 7 (20.6%), SEN/SEN. One patient's genotype (2.9%) was CAR/SEN. The betaA-globin haplotype distribution in Salvador is unusual compared with other Brazilian states. Our data support the hypothesis of multiple post-Columbian introductions of African HTLV-Ia strains in Salvador, Bahia, Brazil.

No evidence of vertical transmission of HTLV-I in bottle-fed children

The most frequent pathway of vertical transmission of HTLV-I is breast-feeding, however bottle fed children may also become infected in a frequency varying from 4 to 14%. In these children the most probable routes of infection are transplacental or contamination in the birth canal. Forty-one bottle-fed children of HTLV-I seropositive mothers in ages varying from three to 39 months (average age of 11 months) were submitted to nested polymerase chain reaction analysis (pol and tax genes). 81.5% of the children were born by an elective cesarean section. No case of infection was detected. The absence of HTLV-I infection in these cases indicates that transmission by transplacental route may be very infrequent.