Human T-cell Lymphotropic Virus Type I Seropositivity Research Articles

Infección por el HTLV-I en pacientes con síndromes linfoproliferativos en dos sitios centinela de Cuba

To determine the prevalence of human T-cell lymphotropic virus type I (HTLV-I) infection among patients with lymphoproliferative disorders, as well as among their family members and sexual contacts, at two sentinel sites in Cuba. An analysis was conducted of all the patients with a presumptive diagnosis of hematological malignancies seen by the hematology departments of the Hospital Hermanos Ameijeiras (HHA), City of Havana, and the Hospital Provincial Comandante Faustino Pérez (HPCFP), Matanza, Cuba, in January 1996-January 1997. HTLV-I seropositivity was determined by ELISA and Western Blot, and infection was confirmed by polymerase chain reaction. The positive patients' family members and sexual contacts were also assessed. The Z-test was used to compare proportions. Seroprevalence of HTLV-I infection in patients with lymphoproliferative disorders was 0.4% higher at the HPCFP than at the HHA (6.1% versus 0.2%, P<0.001). There were no significant differences in prevalence by age, sex, or skin color. Of the 53 family members and sexual contacts studied, 8 (15.1%) were positive for HTLV-I infection. The prevalence of HTLV-I in the study group was higher than previously found in Cuba. The value of seroepidemiological surveillance through sentinel sites was confirmed.

Seroprevalence and demographic characteristics of HTLV-I among blood donors in Taiwan: 1996-1999.

Screening for the human T-cell lymphotropic virus type I (HTLV-I) and-II in blood donors was implemented in Taiwan beginning in February 1996. The purpose of the present study was to investigate the changes in HTLV-I seroprevalence in all unpaid blood donors in Taiwan during the period from February 1996 to December 1999 and to determine the influence of age and sex on the HTLV-I seropositivity of donors. HTLV-I and HTLV-II screening was performed using combined HTLV-I/II immunoassay. Repeated reactive samples were confirmed by Western blot analysis. Of a total of 3,701,087 donors in all 6 blood centers in Taiwan, 2,311 (0.058%) were seropositive for HTLV-I. The HTLV-I seropositivity was 0.130%, 0.063%, 0.044%, and 0.032% in the years 1996, 1997,1998, and 1999, respectively. There was a linear increase of HTLV-I seropositivity with advancing age. The HTLV-I carrier rate for female donors was twice that for the male donors. Ninty-seven percent of HTLV-I seropositive results came from first-time donors. Our findings suggest that Taiwan is a low-prevalence nonendemic area for HTLV-I infection. The large-scale HTLV-I screening program has decreased HTLV-I seropositivity among blood donors and is useful for preventing HTLV-I transmission via blood transfusion.

Geographical clustering of human T-cell lymphotropic virus type I in Guadeloupe, an endemic Caribbean area.

Between January 1989 and December 1996, 59,426 blood donors from Guadeloupe (French West Indies) were screened for antibodies to human T-cell lymphotropic virus type I (HTLV-I). Of these, 195 were confirmed as being positive for HTLV-I, yielding an overall prevalence of 0.33% [95% confidence interval (CI) 0.28-0.38]. On multiple logistic regression analysis, risk factors for HTLV-I were female gender [odds ratio (OR) 1.8; CI 1.3-2.4], increasing age (30-39 years, OR 2.2, CI 1.4-3.4; 40-49 years, OR 3.1, CI 2.1-4.7; > or =50 years, OR 5.6, CI 3.6-8.6) and positive hepatitis B core antibodies (OR 2.0; CI 1.5-2.8). HTLV-I seropositivity was also significantly associated with current residence in certain areas, highlighting microgeographic clustering: individuals living along the Atlantic Facade of Guadeloupe, which is a traditional sugar cane plantation area where Africans were brought during slave trading, were at increased risk for HTLV-I infection (OR 1.9; CI 1.3-2.7) compared with other areas in Guadeloupe devoted to other activities. Our report of HTLV-I cluster identification in Guadeloupe probably reflects both its low spread and its highly intrafamilial restricted transmission within this endemic Caribbean population.

Intrafamilial transmission of HTLV-I and its association with anti-Tax antibody in an endemic population in Japan.

To assess the relationship of anti-Tax antibody to human T-cell lymphotropic virus type-I (HTLV-I) transmission, the sero-prevalence of HTLV-I was analyzed among married couples and among mother/child (both adults) pairs. HTLV-I seroprevalence was significantly higher among wives with anti-Tax+ than those with anti-Tax- HTLV-I carrier husbands (82.4% vs. 59.5%). However, in the group of wives aged 60 years or older, there was no statistical difference in HTLV-I seropositivity based on the husbands' anti-Tax sero-status. In the group whose wives were less than 60 years old, more anti-Tax sero-positive than sero-negative husbands had high DNA levels (57.1% and 20.0%), whereas in the group of husbands whose wives were aged 60 years or older, the number of anti-Tax sero-positive and sero-negative individuals with high DNA levels was similar. HTLV-I sero-prevalence was significantly higher among the adult men with anti-Tax+ carrier mothers than those with anti-Tax- carrier mothers (52.0% vs. 14.3%). For women, HTLV-I sero-prevalence did not differ significantly according to their mothers' anti-Tax sero-status. Our results suggest that the presence of anti-Tax antibody in HTLV-I carriers is an age-dependent risk factor for male-to-female HTLV-I transmission. Furthermore, the effect of the mother's anti-Tax antibody as a risk factor for vertical HTLV-I transmission could be observed in men even after becoming adults.

Risk Factors and Cofactors for Human T-Cell Lymphotropic Virus Type I (HTLV-I)-associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP) in Jamaica

Human T-cell lymphotropic virus type I (HTLV-I) has been etiologically associated with a neurologic syndrome called HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) as well as with adult T-cell leukemia/lymphoma. The authors sought to quantify the risk in Jamaica of HAM/TSP associated with HTLV-I infection and cofactors associated with this disease among infected individuals. Between 1988 and 1989, prevalent and incident HAM/TSP patients and controls with other neurologic diseases were enrolled in a retrospective study. A second control group was composed of HTLV-I-seropositive, asymptomatic carriers in Jamaica, ascertained in a separate study conducted in 1988. Although HTLV-I seropositivity was not a component of the case definition for HAM/TSP, all 43 HAM/TSP patients were HTLV-I seropositive compared with two (4.0%) of the controls with other neurologic diseases. Given HTLV-I seropositivity, one cofactor associated with the risk of HAM/TSP was young age at initial heterosexual confidence interval 1.29-12.46 for individuals aged < or = 15; odds ratio = 4.26, 95% confidence interval 1.41-12.90 for individuals aged 16-17 years at initial intercourse). Among individuals who reported this early age at initial sexual intercourse, an increased risk of HAM/TSP was associated with having reported more than five lifetime sexual partners (odds ratio = 2.88, 95% confidence interval 0.90-8.70). Neither an early age at initial sexual intercourse or the number of lifetime sexual partners was a risk factor for adult T-cell leukemia/lymphoma. These data support the hypothesis that HAM/TSP is associated with sexually acquired HTLV-I infection, whereas adult T-cell leukemia/lymphoma is not.

Risk Factors for Maternal HTLV-I Infection in French Guiana

The aim of this study was to compare rates of human T-cell lymphotropic virus type I (HTLV-I) seroprevalence in pregnant women belonging to different ethnic groups in French Guiana and to determine the risk factors associated with HTLV-I seropositivity. All 1,873 deliveries between 1 July 1991 and 30 June 1993 in the only gynecologic and obstetric unit at Saint Laurent du Maroni were enrolled. Serologic status could be established for 1,727 women, with 75 (4.3%) being HTLV-I seropositive. The HTLV-I seroprevalence rate differed significantly between ethnic groups: 5.7% for Noir-Marron (70/1,302), 6.3% for Haitian (3/50), and 0% for Creole (126), Amerindians (166), and Hmong (64). In Noir-Marron pregnant women, HTLV-I seropositivity was associated with a maternal age of > 35 years [odds ratio (OR), 3.3; 95% confidence interval (CI), 1.4-7.6], prior miscarriage (OR, 1.7; CI, 1-2.8), prior cesarean section (OR, 2.1; CI, 1.1-4.0), a parity > 4 (OR, 4.0; CI, 1.8-8.8), a gravidity > 6 (OR, 4.2; CI, 2.0-7.2), and a negative Rhesus factor (OR, 2.2; CI, 1.1-4.5). Two separate stepwise logistic regressions were done because gravidity and parity were highly correlated. HTLV-I seropositivity remained associated with a gravidity > 6 (OR, 3.9; CI, 2.1-7.4) and a negative Rhesus factor (OR, 2.6; CI, 1.2-5.3) for the first model and with a parity > 4 (OR, 4.1; CI, 1.9-9.0) and a negative Rhesus factor (OR, 2.5; CI, 1.2-5.1) for the second model.(ABSTRACT TRUNCATED AT 250 WORDS)

Human T cell lymphotropic virus type I infection among female sex workers in Peru.

Four hundred female sex workers attending a sexually transmitted disease clinic in Lima, Peru, were interviewed for demographic information and medical, contraceptive, and sexual practice histories. Cervical cultures were done for Neisseria gonorrhoeae and Chlamydia trachomatis, and serum was tested for antibodies to human immunodeficiency virus, human T cell lymphotropic virus type I (HTLV-I), Treponema pallidum, C. trachomatis, herpes simplex virus type 2 (HSV-2), and Haemophilus ducreyi. The prevalence of HTLV-I increased with duration of prostitution from 3.6% (< 3 years) to 9.3% (3-6 years) to 15.9% (> 6 years; P < .01). After adjustment for duration of prostitution, reduced risk of HTLV-I was significantly correlated with condom use for more than half of all sexual exposures for > 3 years (odds ratio [OR], 0.34; 95% confidence interval [CI], 0.13-0.89). Further adjusting for condom use, HTLV-I seropositivity was associated with C. trachomatis (OR, 3.7; 95% CI, 1.4-13.2) and with antibody to HSV-2 (OR, 3.7; 95% CI, 0.5-29.6). Thus, duration of prostitution, lack of consistent condom use, and past infection with C. trachomatis were significantly associated with HTLV-I seropositivity.

Decreased reactivity to PPD among HTLV-I carriers in relation to virus and hematologic status.

Data on human T-cell lymphotropic-virus-type-I (HTLV-I) status and hematology from 528 individuals were analyzed for associations with low reactivity to the purified protein derivative (PPD) of Mycobacterium tuberculosis recall antigen. Subjects were classified as HTLV-I carriers with abnormal lymphocytes (Ably), carriers without Ably, and seronegatives. All carriers had a significant 2.6-fold risk of being low responders to PPD compared with the seronegatives, carriers with Ably having the highest relative risk. Carriers with HTLV-I-antibody titer > or = 1:256, or with other detectable markers of virus status such as antibody to tax and proviral DNA, had increased risk for low response to PPD similar to the estimate for HTLV-I seropositivity alone, compared with the seronegatives. Subjects with a low lymphocyte count had 3.5 times the risk for being low responders to PPD, compared with subjects with high counts. Similarly, subjects with a low monocyte count had 2.0 times the risk for low reactivity of those with a moderate to high count. Results were not confounded by age, sex, smoking or alcohol drinking. Using multiple logistic regression, only HTLV-I seropositivity and low lymphocyte and monocyte counts were predictive of low reactivity to PPD. Analysis indicates that suppression of delayed-type hypersensitivity is associated with HTLV-I infection per se, and not with viral replication or load. Furthermore, this effect may occur in part via changes in the number and function of lymphocytes and monocytes. Such a mechanism may involve altered cytokine production in carriers and concomitant changes in cell populations involved in delayed-type hypersensitivity.

Role of HTLV-I in development of non-Hodgkin lymphoma in Jamaica and Trinidad and Tobago

Human T-cell lymphotropic virus type I (HTLV-I) has been implicated in the aetiology of adult T-cell leukaemia/ lymphoma in Japan and elsewhere, particularly the Caribbean. We have carried out parallel case-control studies in Jamaica and in Trinidad and Tobago to quantify the role of HTLV-I in the development of non-Hodgkin lymphoma (NHL). 135 cases of NHL were enrolled in Jamaica and 104 in Trinidad and Tobago. Controls were selected from patients treated in the same wards or clinics at the same time as the cases. Overall, patients with NHL were 10 times more likely than were controls to be seropositive for HTLV-I (Jamaica odds ratio 10·3 [95% Cl 6·0-18·0], Trinidad and Tobago 14·4 [7·6-27·2]). In both countries the association between NHL and HTLV-I was greatest for T-cell lymphomas (18·3 [9·5-35·6] and 63·3 [25-167]). Among T-cell lymphomas especially, there was no significant difference between men and women in the association between NHL and HTLV-I, but there was a significant inverse relation between age and likelihood of HTLV-I seropositivity. B-cell lymphomas were predominant in the older age groups and were not associated with HTLV-I seropositivity. These findings are consistent with the hypothesis that early life exposure to HTLV-I is important for risk of subsequent ATL. Prevention of vertical transmission of HTLV-I could reduce by 70-80% cases of NHL in people under 60 years in this region.

Human T-cell lymphotropic virus type I infection and pregnancy: A case-control study and 12-month follow-up of 135 women and their infants

Human T-cell lymphotropic virus type I (HTLV-I) infection is common in Gabon, but its influence on pregnancy is unknown. A single case of acute T-cell leukemia in a pregnant woman has been reported in the literature, but, as far as we know, we present the first case-control study analyzing the relationship between HTLV-I seropositivity and the course and outcome of pregnancy. The study concerned 45 HTLV-I seropositive pregnant women matched with 90 seronegative pregnant women. None has clinical features of HTLV-I infection during pregnancy or during the year after delivery. HTLV-I seropositivity did not significantly affect the course or outcome of pregnancy. After losing maternal antibodies to HTLV-I, none of the infants had seroconversion to HTLV-I 1 year after birth. Filaria infection was correlated with HTLV-I seropositivity, but confounding factors may account for this observation.

Human T-cell lymphotropic virus type I infection and pregnancy: A case-control study and 12-month follow-up of 135 women and their infants

Human T-cell lymphotropic virus type I (HTLV-I) infection is common in Gabon, but its influence on pregnancy is unknown. A single case of acute T-cell leukemia in a pregnant woman has been reported in the literature, but, as far as we know, we present the first case-control study analyzing the relationship between HTLV-I seropositivity and the course and outcome of pregnancy. The study concerned 45 HTLV-I seropositive pregnant women matched with 90 seronegative pregnant women. None has clinical features of HTLV-I infection during pregnancy or during the year after delivery. HTLV-I seropositivity did not significantly affect the course or outcome of pregnancy. After losing maternal antibodies to HTLV-I, none of the infants had seroconversion to HTLV-I 1 year after birth. Filaria infection was correlated with HTLV-I seropositivity, but confounding factors may account for this observation.

A survey of the human T-cell lymphotropic virus type I (HTLV-I) in south-western Colombia.

To evaluate altitude of birthplace and residence as factors associated with geographic clustering of HTLV-I infection in Colombia, we sampled a total of 670 current residents of the South Pacific coastal lowland and of upland regions (Cali and environs) of the Valle and Cauca Provinces, located at an altitude of 3,100 ft. Among the 255 lowland study subjects, 4.3% had antibody against HTLV-I, compared to 0.9% of the 415 upland study subjects. A hypothesis emerging from this study is that the lower socio-economic status of lowland residents and associated diseases, particularly untreated syphilis and other sexually transmitted diseases, may explain the increased HTLV-I seropositivity rates in this population.