Prevalence of retrovirus, hepatitis B and D infection in the Matsés ethnic group in Loreto, Peru. / Prevalencia de infección por los virus de la hepatitis B, D y por retrovirus en la etnia Matsés (Loreto, Perú).

Observational, cross-sectional, populational study to determine the prevalence of infection by hepatitis B virus (HBV), hepatitis D virus (HDV), human immunodeficiency virus (HIV) and human T-lymphotropic virus type 1 and 2 (HTLV-1/2) in the Matsés ethnic group, after immunization against HBV. ELISA and qPCR tests were used in 963 residents. The prevalence of HBsAg, Anti-HBc and Anti-HBs was 3.32%, 36.03% and 58.67% respectively. In 3.1% of the population the viral load was greater than 2000 IU/mL. In children under 10 years, the prevalence of HBsAg and anti-HBc was 0.0% and 2.6%, respectively, while protective antibodies were found in 94.4%. The prevalence of HIV and HTLV-1/2 infection was 1.5% and 0.6%, respectively. It is therefore concluded that there are low rates of HBV and HDV infection in the Matsés child population. Likewise, the presence of HIV and HTLV-1/2 infection is confirmed.

Para determinar la prevalencia de infección por los virus de la hepatitis B y D (VHB y VHD, respectivamente), VIH y HTLV-1/2 en la etnia matsés, después de la inmunización contra el VHB se realizó un estudio transversal y poblacional, utilizando pruebas de ELISA y qPCR en 963 pobladores. Las prevalencias de HBsAg, anti-HBc y anti-HBs fueron 3,3%, 36,0% y 58,7%, respectivamente. En el 3,1% de la población la carga viral fue mayor a 2000 UI/mL. En menores de 10 años, la prevalencia de HBsAg y anti-HBc fue 0,0% y 2,6%, respectivamente, mientras que en el 94,4% se encontraron anticuerpos protectores. La prevalencia de infección por el VIH y el HTLV-1/2 fue 1,5% y 0,6%, respectivamente. Se concluye que existen tasas bajas de infección por el VHB y el VHD en la población infantil de la etnia matsés. Asimismo, se confirma la presencia de infección por el VIH y el HTLV-1/2.

HTLV screening of blood donors using chemiluminescence immunoassay in three major provincial blood centers of China.

BACKGROUND: Human T-cell lymphotropic virus (HTLV) remains a major safety concern for blood supplies. Despite many HTLV positive cases being reported in southeastern China, the detection of HTLV has not been prioritized in routine blood screening. Additionally, data on the prevalence of HTLV infection among blood donors is also limited. The objective of this study was to investigate the prevalence of HTLV among blood donors in three Chinese provinces through their representative blood centers, to evaluate the feasibility of chemiluminescence immunoassay (CLIA) for blood screening. METHODS: From November 2018 to March 2019, blood plasma samples were collected from Hebei, Changsha, and Shenzhen blood centers and were screened for the HTLV-1/2 antibody using a CLIA and enzyme-linked immunosorbent assay (ELISA). This was followed by confirmatory tests using INNO-LIA HTLV I/II. RESULTS: A total of 59,929 blood donations were collected and screened for HTLV-1/2. The reactive rate of CLIA and ELISA among donations in the Shenzhen blood center (0.0943%, 27/28,621) was higher than Hebei (0.0248%, 4/16,144), and Changsha (0.0198%, 3/15,164) (p < 0.05). After confirmation, 3 samples were confirmed as indeterminate for HTLV antibodies, and only one sample from the Shenzhen blood center was confirmed as HTLV-1. The overall prevalence of HTLV-1/2 was 1.67 per 100,000 (1/59,929). The HTLV-infected blood came from a 32-year-old first-time female donor with a high school degree, who belonged to the SHE ethnic minority and was born in the Fujian province. CONCLUSIONS: In summary, the overall prevalence of HTLV-1/2 among blood donors in the three blood centers in China remains relatively low. However, blood donations with positive or indeterminate results for HTLV antibodies reminded us of the importance of HTLV screening among blood donors in China.

Prevalencia de infección por los virus de la hepatitis B, D y por retrovirus en la etnia Matsés (Loreto, Perú) / Prevalence of retrovirus, hepatitis B and D infection in the Matsés ethnic group in Loreto, Peru

RESUMEN Para determinar la prevalencia de infección por los virus de la hepatitis B y D (VHB y VHD, respectivamente), VIH y HTLV-1/2 en la etnia matsés, después de la inmunización contra el VHB se realizó un estudio transversal y poblacional, utilizando pruebas de ELISA y qPCR en 963 pobladores. Las prevalencias de HBsAg, anti-HBc y anti-HBs fueron 3,3%, 36,0% y 58,7%, respectivamente. En el 3,1% de la población la carga viral fue mayor a 2000 UI/mL. En menores de 10 años, la prevalencia de HBsAg y anti-HBc fue 0,0% y 2,6%, respectivamente, mientras que en el 94,4% se encontraron anticuerpos protectores. La prevalencia de infección por el VIH y el HTLV-1/2 fue 1,5% y 0,6%, respectivamente. Se concluye que existen tasas bajas de infección por el VHB y el VHD en la población infantil de la etnia matsés. Asimismo, se confirma la presencia de infección por el VIH y el HTLV-1/2.

ABSTRACT Observational, cross-sectional, populational study to determine the prevalence of infection by hepatitis B virus (HBV), hepatitis D virus (HDV), human immunodeficiency virus (HIV) and human T-lymphotropic virus type 1 and 2 (HTLV-1/2) in the Matsés ethnic group, after immunization against HBV. ELISA and qPCR tests were used in 963 residents. The prevalence of HBsAg, Anti-HBc and Anti-HBs was 3.32%, 36.03% and 58.67% respectively. In 3.1% of the population the viral load was greater than 2000 IU/mL. In children under 10 years, the prevalence of HBsAg and anti-HBc was 0.0% and 2.6%, respectively, while protective antibodies were found in 94.4%. The prevalence of HIV and HTLV-1/2 infection was 1.5% and 0.6%, respectively. It is therefore concluded that there are low rates of HBV and HDV infection in the Matsés child population. Likewise, the presence of HIV and HTLV-1/2 infection is confirmed.

[Human T-cell lymphotropic virus type 1 (HTLV-1): a forgotten pathogen]. / Het humaan T-cellymfotroop virus type 1.

HTLV-1 is a retrovirus endemic to different parts of the world that causes a variety of symptoms, ranging from asymptomatic infection to severe diseases such as lymphoma/leukaemia and myelopathy. HTLV-1 is transmitted from mother to child through breastfeeding, sexually and via blood and organ donation. We describe 3 patients as examples of the distinct clinical problems related to HTLV-1: a 53-year-old woman with HTLV-1-associated myelopathy, a 43-year-old woman with acute T-cell lymphoma and a 34-year-old pregnant woman who is an asymptomatic carrier. It is not known how many people are infected in the Netherlands, but it is probably more prevalent among immigrants from the Caribbean and Surinam and likely to be underdiagnosed. Diagnosis is important because it alters treatment and because measures to prevent transmission can be implemented, e.g. refraining from breastfeeding and safe sex precautions.

Human T-Lymphotropic Virus type 1c subtype proviral loads, chronic lung disease and survival in a prospective cohort of Indigenous Australians.

BACKGROUND: The Human T-Lymphotropic Virus type 1c subtype (HTLV-1c) is highly endemic to central Australia where the most frequent complication of HTLV-1 infection in Indigenous Australians is bronchiectasis. We carried out a prospective study to quantify the prognosis of HTLV-1c infection and chronic lung disease and the risk of death according to the HTLV-1c proviral load (pVL). METHODOLOGY/PRINCIPAL FINDINGS: 840 Indigenous adults (discharge diagnosis of bronchiectasis, 154) were recruited to a hospital-based prospective cohort. Baseline HTLV-1c pVL were determined and the results of chest computed tomography and clinical details reviewed. The odds of an association between HTLV-1 infection and bronchiectasis or bronchitis/bronchiolitis were calculated, and the impact of HTLV-1c pVL on the risk of death was measured. Radiologically defined bronchiectasis and bronchitis/bronchiolitis were significantly more common among HTLV-1-infected subjects (adjusted odds ratio = 2.9; 95% CI, 2.0, 4.3). Median HTLV-1c pVL for subjects with airways inflammation was 16-fold higher than that of asymptomatic subjects. There were 151 deaths during 2,140 person-years of follow-up (maximum follow-up 8.13 years). Mortality rates were higher among subjects with HTLV-1c pVL ≥1000 copies per 105 peripheral blood leukocytes (log-rank χ2 (2df) = 6.63, p = 0.036) compared to those with lower HTLV-1c pVL or uninfected subjects. Excess mortality was largely due to bronchiectasis-related deaths (adjusted HR 4.31; 95% CI, 1.78, 10.42 versus uninfected). CONCLUSION/SIGNIFICANCE: Higher HTLV-1c pVL was strongly associated with radiologically defined airways inflammation and with death due to complications of bronchiectasis. An increased risk of death due to an HTLV-1 associated inflammatory disease has not been demonstrated previously. Our findings indicate that mortality associated with HTLV-1c infection may be higher than has been previously appreciated. Further prospective studies are needed to determine whether these results can be generalized to other HTLV-1 endemic areas.

Turning a blind eye: HTLV-1-associated uveitis in Indigenous adults from Central Australia.

PURPOSE: We describe the first two cases of HTLV-1 associated uveitis to be associated with HTLV-1c subtype infection. METHODS: Case report. RESULTS: Uveitis was demonstrated in two Indigenous Australian men, both of whom had high HTLV-1c proviral loads in peripheral blood. Visual outcomes were poor in each case. CONCLUSION: Clinicians should be aware of HTLV-1c infection as a cause of uveitis in Australia, and HTLV-1 serology should be included in the basic uveitis work-up in HTLV-1-endemic areas.

The prevalence and clinical associations of HTLV-1 infection in a remote Indigenous community.

OBJECTIVE: Hospital and laboratory data indicate that human T-lymphotropic virus type 1 (HTLV-1) is endemic to central Australia, but no community-based studies of its prevalence or disease burden have been reported. We determined the prevalence rates of HTLV-1 infection and of HTLV-1-associated diseases in a remote Indigenous community. SETTING: A remote Northern Territory community. DESIGN: All residents were asked to complete a health survey and offered a limited clinical examination, together with serological tests for HTLV-1 and Strongyloides, and HTLV-1 proviral load (PVL) assessment. MAIN OUTCOME MEASURES: HTLV-1 seropositivity rates; HTLV-1 PVL (copies/105 peripheral blood leucocytes [PBL]); presentation with HTLV-1-related clinical disease. RESULTS: HTLV-1 serostatus was determined for 97 of 138 residents (70%). The prevalence of HTLV-1 infection was significantly higher among adults (30 of 74 people tested) than children (1 of 23; P = 0.001). Nine of 30 HTLV-1-positive adults had a clinical syndrome that was potentially attributable to HTLV-1 infection (chronic lung disease, seven; symptomatic strongyloidiasis, two). The median HTLV-1 PVL was significantly higher for adults with chronic lung disease than for those who were asymptomatic (chronic lung disease, 649 copies/105 PBL [IQR, 162-2220]; asymptomatic adults, 40 copies/105 PBL [IQR, 0.9-229]; P = 0.017). Ten of 72 adults tested were seropositive for Strongyloides (six of 28 HTLV-1-positive participants and four of 44 HTLV-1-negative participants; P = 0.17), as were three of 15 children tested; the three children were HTLV-1-negative. CONCLUSION: The prevalence of HTLV-1 infection and the rate of disease potentially attributable to HTLV-1 were high among adults in this remote community.

Prevalence and phylogenetic analysis of HTLV-1 in a segregated population in Iran.

Human T-lymphotropic virus type 1 (HTLV-1) infection is an important health issue that affects a variety of endemic areas. The Khorasan province, mainly its capital Mashhad in northeastern Iran, was reported to be as one of these endemic regions. Torbat-e Heydarieh, a large city Southwest border to Mashhad with a segregated population was investigated for the prevalence and associated risk factors of HTLV-1 infection in 400 randomly selected individuals. Blood samples were tested for the presence of HTLV-1 antibodies via the ELISA method and then were confirmed by an Immunoblot test. For the presence of HTLV-1 in lymphocytes of infected subjects, PCR was performed on LTR and TAX regions. DNA sequencing of LTR fragment was also carried out to determine the phylogenetic of HTLV-1, using the Maximum likelihood method. HTLV-1 sero-reactivity (sero-prevalence) among the study population was 2% (8/400), of which 1.25% had HTLV-1 provirus in lymphocytes (actual prevalence). HTLV-1 infection was significantly associated with the age, marital status, and history of blood transfusion (P < 0.05). However, there were no statistical differences between HTLV-1 infection, and gender, surgery, and hospitalization. In regression analysis, age showed the most significant correlation with the infection (P = 0.006, OR = 4.33). Based on our phylogenetic study, the HTLV-1 prevalent sequence type of Torbat-e Heydarieh belongs to the cosmopolitan subtype A. HTLV-1 prevalence in Torbat-e Heydarieh (1.25%) is low comparing to those of both Mashhad (2-3%) and Neishabour (3.5-5%) in the province of Khorasan. Thus, traveling mobility and population mixing such as marriage, bureaucratic affairs, occupation, and economic activities could be the usual routs of HTLV-1 new wave of spreading in this segregated city.

Serological study of Trypanosoma cruzi, Strongyloides stercoralis, HIV, human T cell lymphotropic virus (HTLV) and syphilis infections in asymptomatic Latin-American immigrants in Spain.

OBJECTIVE: We aimed to perform a serological screening for T. cruzi, Strongyloides stercoralis, HIV, human T cell lymphotropic virus (HTLV) and syphilis in Latin American immigrants admitted to hospital in Spain. METHODS: We have carried out a cross-sectional study of Latin American immigrants admitted to the Hospital General Universitario Alicante (Spain) from June 2012 to May 2014, where screening of Chagas disease, strongyloidiasis, HTLV, HIV and syphilis was performed by serology. RESULTS: A total 180 patients were included in the study. Patients' median age was 38 years old, 123 (68.3%; 123/180) were female and 57 (31.7%; 57/180) male. Five of the 180 (2.5%) patients were positive for Chagas disease; associated with knowledge about Chagas disease (p=0.005), previous contact with patients with Chagas disease (p=0.04) and being Bolivian (p<0.001). Forty-two of the 157 (26.8%) patients were positive for Strongyloides serology; associated positively with being male (p<0.001), eosinophilia (p=0.001), hyper-IgE (p<0.001) and being Ecuadorian (p=0.001), and negatively associated with being Colombian (p=0.03). Positive serology of latent syphilis was found in 1.8% (3/171) of patients. Serology of HTLV was negative in all cases. No new cases of HIV infection were diagnosed. CONCLUSIONS: We propose that Latin American immigrant patients admitted to hospital in Spain be screened for strongyloidiasis, Chagas disease and syphilis by serology.

Insights into origins of Human T-cell Lymphotropic Virus Type 1 based on new strains from aboriginal people of Canada.

The causes of the worldwide distribution of Human T-cell Lymphotropic Virus Type 1 (HTLV-1) remain incompletely understood, with competing hypotheses regarding the number and timing of events leading to intercontinental spread on historical and prehistoric timescales. Ongoing discovery of this virus in aboriginal populations of Asia and the Americas has been the main source of evidence for the latter. We conducted molecular phylogenetic and dating analyses for 13 newly reported HTLV-1 strains from Canada. We analyzed two full-length proviral genomes from aboriginal residents of Nunavut (an autonomous territory in Northern Canada including most of the Canadian Arctic), 11 long-terminal-repeat (LTR) sequences from aboriginal residents of British Columbia's Pacific coast, and 2 LTR sequences from non-aboriginal Canadians. Phylogenetic analysis demonstrated a well-supported affinity between the two Nunavut strains and two East Asian strains, suggesting the presence of an Asian-American sublineage within the widespread "transcontinental" subgroup A clade of HTLV-1 Cosmopolitan subtype a. This putative sublineage was estimated to be 5400-11,900 years in age, consistent with a long-term presence of HTLV-1 in aboriginal populations of the Canadian Arctic. Phylogenetic affinities of the other 11 Canadian HTLV-1 aboriginal strains were diverse, strengthening earlier evidence for multiple incursions of this virus into coastal aboriginal populations of British Columbia. Our results are consistent with the hypothesis of ancient presence of HTLV-1 in aboriginal populations of North America.

Stable human T-cell lymphotropic virus type 1 (HTLV-1) subtype a/subgroup a endemicity in Amerindians from Northwest Argentina: a health problem to be resolved.

Jujuy province, in Northwest Argentina, is known to be endemic for HTLV-1 infection. Moreover, foci of HTLV-1 associated pathologies have also been described in this region. To gain an insight into the current situation of HTLV-1/2 in this endemic area, a seroprevalence and phylogenetic study was performed among a Kolla community from Abra Pampa city and surroundings. Out of 112 individuals, 11 (9.8%) were confirmed as HTLV-1 positive and no HTLV-2 infection was detected. The phylogenetic analysis of the LTR region showed that all the HTLV-1 sequences belonged to the Cosmopolitan subtype a/transcontinental subgroup A, and were closely related to reference sequences from Peru, Argentina, and the South of Brazil (P = 0.82). Considering the cultural and historical features of this community and in spite of the mandatory detection of anti-HTLV-1/2 antibodies in blood banks since 2005, it would be important to implement new public health measures focused on decreasing HTLV-1 transmission in this endemic area.

Trends in the seroprevalence of HTLV-1 in Japanese blood donors in Nagasaki Prefecture, 2000-2006.

Human T cell leukemia virus type-1 (HTLV-1) is the established cause of adult T cell leukemia/lymphoma. Monitoring time trends in HTLV-1 seroprevalence in blood donors is important to assess the safety of the blood supply in the viral endemic area. We analyzed changes in HTLV-1 seroprevalence in 48415 first-time blood donors who donated blood from 2000 to 2006 in Nagasaki prefecture, an endemic area in Japan. The donors were divided into 10-year birth cohorts: before 1950, 1951-1960, 1961-1970, 1971-1980, and 1981-1990. Among the first-time blood donors, 622 were tested positive for HTLV-1 [overall seroprevalence: 1.28%, (95% CI 1.19-1.39)]. Seroprevalence was significantly high in the birth cohort of before 1950 (6.22%) and declined with birth-year. The time trend of the birth-cohort-specific seroprevalence showed almost no change within each birth cohort, except for the birth cohort of 1981-1990 that showed a significantly declining trend (P for trend = 0.006). Among the birth cohort of 1981-1990, the seroprevalence was stable among those born during 1981-1986 (0.66-0.83%), but was lower among those born during 1987-1990 (0-0.38%). Detail analyses showed that HTLV-1 seroprevalence among blood donors clearly declined in those born after 1987.

DC-SIGN (CD209) gene promoter polymorphisms in a Brazilian population and their association with human T-cell lymphotropic virus type 1 infection.

This study evaluated four polymorphisms located in the DC-SIGN (CD209) gene promoter region (positions -336, -332 -201 and -139) in DNA samples from four Brazilian ethnic groups (Caucasians, Afro-Brazilian, Asians and Amerindians) to establish the population distribution of these single-nucleotide polymorphisms (SNPs) and correlated DC-SIGN polymorphisms and infection in samples from human T-cell lymphotropic virus type 1 (HTLV-1)-infected individuals. To identify CD209 SNPs, 452 bp of the CD209 promoter region were sequenced and the genotype and allelic frequencies were evaluated. This is the first study to show genetic polymorphism in the CD209 gene in distinct Brazilian ethnic groups with the distribution of allelic and genotypic frequency. The results showed that -336A and -139A SNPs were quite common in Asians and that the -201T allele was not observed in Caucasians, Asians or Amerindians. No significant differences were observed between individuals with HTLV-1 disease and asymptomatic patients. However, the -336A variant was more frequent in HTLV-1-infected patients [HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), 80 %; healthy asymptomatic HTLV-1 carriers, 90 %] than in the control group (70 %) [P=0.0197, odds ratio (OR)=2.511, 95 % confidence interval (CI)=1.218-5.179). In addition, the -139A allele was found to be associated with protection against HTLV-1 infection (P=0.0037, OR=0.3758, 95 % CI=0.1954-0.7229) when the HTLV-1-infected patients as a whole were compared with the healthy-control group. These observations suggest that the -139A allele may be associated with HTLV-1 infection, although no significant association was observed among asymptomatic and HAM/TSP patients. In conclusion, the variation observed in SNPs -336 and -139 indicates that this lectin may be of crucial importance in the susceptibility/transmission of HTLV-1 infections.

Strongyloides stercoralis: a cause of morbidity and mortality for indigenous people in Central Australia.

BACKGROUND: Strongyloides stercoralis may cause a complicated infection in immunocompromised patients, which has a high case fatality rate. Death generally results from sepsis with enteric pathogens. Globally, infection with the human T-cell lymphotropic virus type 1 (HTLV-1) is a major risk factor for this syndrome. Both S. stercoralis and HTLV-1 are endemic to Central Australia. AIMS: The aim of the study was to determine whether complicated strongyloidiasis occurs in association with HTLV-1 infection in Central Australia. METHODS: A retrospective audit of all cases of complicated strongyloidiasis presenting to Alice Springs Hospital between January 2000 and December 2006 was carried out. Diagnosis was defined as definite or probable according to whether diagnosis was made by faecal studies or serology respectively. The medical records, investigations and outcomes of patients who met predetermined criteria for a diagnosis of complicated strongyloidiasis were reviewed. RESULTS: Eighteen indigenous patients met the criteria for complicated strongyloidiasis (definite 9, probable 9). Seven of 11 patients tested were HTLV-1 seropositive. At diagnosis, no treatment was documented for nine patients (definite 4, probable 5), three received a single dose of ivermectin and one a single dose of albendazole. Fifteen patients (83%) died because of sepsis (definite 7, probable 8). Pathogens isolated and their foci of infection included Klebsiella pneumoniae pneumonia (4), bloodstream infection with Enterococcus spp. (2), K. pneumoniae peritonitis (1) and streptococcal meningitis (1). CONCLUSION: Complicated strongyloidiasis occurs in association with HTLV-1 infection in central Australia. This finding has significant implications for the management of S. stercoralis in the region.

Frequent HTLV-1 infection in the offspring of Peruvian women with HTLV-1-associated myelopathy/tropical spastic paraparesis or strongyloidiasis.

OBJECTIVES: To describe the frequency of HTLV-1 infection among offspring of mothers who had presented with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), strongyloidiasis, or asymptomatic HTLV-1 infection, and to identify factors associated with HTLV-1 infection. METHODS: In a descriptive study, records were reviewed of HTLV-1-positive women and their offspring who had been tested for HTLV infection at a public hospital in Lima, Peru, from 1989 to 2003. Sons and daughters of women who had presented with strongyloidiasis, HAM/TSP, or asymptomatic infection were eligible for this study. RESULTS: Three hundred seventy subjects were included: 279 were the offspring of 104 mothers presenting with HAM/TSP, 58 were the offspring of 22 mothers with strongyloidiasis, and 33 were the offspring of 26 asymptomatic mothers. Mean age of the offspring at the time of testing was 26 years (standard deviation 12). Nineteen percent of the offspring tested positive for HTLV-1: 6% (2/33) of those with asymptomatic mothers, 19% (52/279) among the offspring of mothers with HAM/TSP, and 31% (18/58) among the offspring of mothers presenting with strongyloidiasis On multiple logistic regression analysis, three factors were significantly associated with HTLV-1: (a) duration of breast-feeding (odds ratio [OR] = 15.1; [4.2-54.1] for 12 to 24 months versus less than 6 months breast-feeding); (b) clinical condition of the mother (OR = 8.3 [1.0-65.3] for HAM/TSP and OR = 11.5 [1.4-98.4] for strongyloidiasis in comparison with offspring of asymptomatic mothers); and (c) transfusion history (OR = 5.5 [2.0-15.2]). CONCLUSIONS: In addition to known risk factors for HTLV-1 transmission (duration of breast-feeding and history of blood transfusion), maternal HAM/TSP and strongyloidiasis were associated with seropositivity among offspring of HTLV-1-infected mothers.

[Analysis of the ethical issues raised by a ten-year epidemiology program in French Guiana: limitations of the current legal framework and solutions adopted]. / Analyse des enjeux éthiques soulevés au cours d'un programme de recherche épidémiologique de dix années en Guyane française : limites de l'encadrement actuel et solutions adoptées.

BACKGROUND: This paper discusses the ethical aspects of a large research program in virology, conducted since 1994 and which has evolved in parallel with the elaboration of bioethics laws in France. This research, which involved the collection of a considerable amount of epidemiological data in the field, focused on epidemiological determinants (mother to child transmission, genetic susceptibility/resistance) of the human oncogenic retrovirus human T cell lymphotropic virus type 1 (HTLV-1). Data were collected from a specific population (Noirs Marrons) living in remote areas in French Guiana (South America). This ethnic group of African descent is highly endemic for HTLV-1 and associated adult T cell leukemia/lymphoma. The population has lived for two centuries on either side of the Maroni river, which constitutes the frontier between French Guiana and Surinam. The low socioeconomic and education levels of a large part of this population are mainly explained by a recent housing/residence fixation on the French side of the Maroni river. It is also linked to significant immigration from Surinam due to the civil war, which lasted for five years in the late 1990s, in this country. Conducting epidemiological surveys in this peculiar context illustrates the limitations of the available current legal framework in France for such studies. Indeed, several important ethical issues arose concerning not only individual and population benefits, but also specificities of the given information and of the informed consent. Another question concerns individual information feed-back in such a context of persistent viral infection, with a very low disease incidence, in a population with a relatively low education level. The goal of this work was mainly to report several of the ethical issues encountered and to discuss possible ways of achieving better information deliver and consent procedures in such a context. Indeed, these procedures should include new ideas and regulations promoting a real partnership, in order to conduct long-term epidemiological studies in populations with a low education level.

Frequent HTLV-1 infection in the offspring of Peruvian women with HTLV-1-associated myelopathy/tropical spastic paraparesis or strongyloidiasis

OBJECTIVES: To describe the frequency of HTLV-1 infection among offspring of mothers who had presented with HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), strongyloidiasis, or asymptomatic HTLV-1 infection, and to identify factors associated with HTLV-1 infection. METHODS: In a descriptive study, records were reviewed of HTLV-1-positive women and their offspring who had been tested for HTLV infection at a public hospital in Lima, Peru, from 1989 to 2003. Sons and daughters of women who had presented with strongyloidiasis, HAM/TSP, or asymptomatic infection were eligible for this study. RESULTS: Three hundred seventy subjects were included: 279 were the offspring of 104 mothers presenting with HAM/TSP, 58 were the offspring of 22 mothers with strongyloidiasis, and 33 were the offspring of 26 asymptomatic mothers. Mean age of the offspring at the time of testing was 26 years (standard deviation 12). Nineteen percent of the offspring tested positive for HTLV-1: 6 percent (2/33) of those with asymptomatic mothers, 19 percent (52/279) among the offspring of mothers with HAM/TSP, and 31 percent (18/58) among the offspring of mothers presenting with strongyloidiasis On multiple logistic regression analysis, three factors were significantly associated with HTLV-1: (a) duration of breast-feeding (odds ratio [OR] = 15.1; [4.2-54.1] for 12 to 24 months versus less than 6 months breast-feeding); (b) clinical condition of the mother (OR = 8.3 [1.0-65.3] for HAM/TSP and OR = 11.5 [1.4-98.4] for strongyloidiasis in comparison with offspring of asymptomatic mothers); and (c) transfusion history (OR = 5.5 [2.0-15.2]). CONCLUSIONS: In addition to known risk factors for HTLV-1 transmission (duration of breast-feeding and history of blood transfusion), maternal HAM/TSP and strongyloidiasis were associated with seropositivity among offspring of HTLV-1-infected mothers.

OBJETIVOS: Describir la frecuencia de la infección por HTLV-1 en los hijos e hijas de madres diagnosticadas con mielopatía/paraparesia espástica tropical asociada con el HTLV-1 (M/PET-HTLV-1), estrongiloidiasis o infección asintomática por HTLV-1, e identificar los factores asociados con la infección por HTLV-1. MÉTODOS: Para este estudio descriptivo se revisaron los registros de mujeres positivas a HTLV-1 y de sus hijos evaluados con pruebas para la infección por HTLV en un hospital público de Lima, Perú, entre 1989 y 2003. Eran elegibles para este estudio los hijos y las hijas de las mujeres que se presentaron con estrongiloidiasis, M/PET-HTLV-1 o infección asintomática. RESULTADOS: En el estudio participaron 370 personas: 279 hijos de 104 madres con M/PET-HTLV-1, 58 hijos de 22 madres con estrongiloidiasis y 33 hijos de 26 madres asintomáticas. La edad promedio de los participantes en el momento de su prueba para HTLV era de 26 años (desviación estándar: 12 años). De las personas estudiadas, 19 por ciento resultaron positivas a la infección por HTLV-1: 6 por ciento (2/33) de los hijos de madres asintomáticas, 19 por ciento (52/279) de los hijos de madres con M/PET-HTLV-1 y 31 por ciento (18/58) de los hijos de madres con estrongiloidiasis. Según el análisis de regresión logística múltiple, tres factores se asociaron significativamente con la infección por HTLV-1: a) duración de la lactancia materna por 12_24 meses (razón de posibilidades [odds ratio, OR] = 15,1; intervalo de confianza de 95 por ciento [IC95 por ciento]: 4,2 a 54,1, frente a la lactancia materna por menos de 6 meses); b) que la madre presentara M/PET-HTLV-1 o estrongiloidiasis (OR = 8,3; IC95 por ciento: 1,0 a 65,3 y OR = 11,5; IC95 por ciento: 1,4 a 98,4, respectivamente, en comparación con los hijos de madres asintomáticas); y c) los antecedentes de haber recibido una transfusión sanguínea (OR = 5,5; IC95 por ciento: 2,0 a 15,2). CONCLUSIONES: Además de los factores...

HTLV-1 infection and the viral etiology of multiple sclerosis.

The HTLV-1 virus produces a progressive inflammatory, and then degenerative, myelopathy which evolves progressively from onset. HTLV-1 in endemic in populations which are recognized as having low risk of multiple sclerosis . Multiple sclerosis generally evolves as a relapsing-remitting disease and affects predominantly Caucasians. In Caucasians, HAM/TSP can be marked by fluctuations as well as relapses. In Asians MS affects preferentially the spinal cord. The author hypothesizes that population selection through environmental factors has pushed the immune response of Caucasians towards generating relapsing-remitting disease and that of Primordial populations towards progressive disease. HTLV-1 endemicity being the marker of Primordial populations and its absence that of Caucasians.