A novel high-performance rapid screening test for the detection of total HTLV-I and HTLV-II antibodies in HTLV-I/II infected patients.

Rapid diagnosis of human T-cell lymphotropic virus (HTLV) type-I and -II infections are essential for timely and cost-effective disease interventions. MP Diagnostics ASSURE HTLV-I/II Rapid Test was developed for the rapid detection of anti-HTLV-I/II antibodies in patients' serum, plasma, and whole blood specimens. ASSURE HTLV-I/II Rapid Test employed MP Biomedicals' proprietary HTLV-I/II Trifusion recombinant antigen conjugated with gold nanoparticles and HTLV-I / HTLV-II recombinant antigens immobilized on the nitrocellulose membrane to detect total HTLV-I and HTLV-II antibodies. The overall performance of the ASSURE HTLV-I/II Rapid Test was found to be 99.42% sensitivity (95% Confidence Interval, 98.32-99.88%) and 100% specificity (95% Confidence Interval, 99.58-100.00%) in the tested clinical samples, including a total of 518 HTLV-I/II positive specimens (396 HTLV-I infection, 97 HTLV-II infection and 25 HTLV-I/II dual infection) and 872 HTLV negative clinical specimens consisting of 691 healthy donor samples, 116 potentially cross-reactive samples, and 65 samples with interfering substances. The ASSURE HTLV-I/II Rapid Test can effectively be deployed as a screening tool in any prevalence studies, blood banks or organ transplant centres.

Seroprevalence of human T-lymphotropic virus infection among blood donors in China: a first nationwide survey.

BACKGROUND: So far, the prevalence of human T-lymphotropic virus (HTLV) type 1 and 2 in some highly populated countries such as China is still unknown. In this study, a multi-center nationwide serological survey was designed and performed, to reveal the seroprevalence of HTLV infection among Chinese blood donors. RESULTS: Among 8,411,469 blood donors from 155 blood establishments, 435 were finally confirmed as HTLV carriers. The prevalence of HTLV infection in China varied in different provinces: Fujian had the highest prevalence of 36.240/100,000 (95% CI 31.990-41.050) and eleven provinces did not find HTLV-seropositive donors in the three years. no HTLV-2 infection was found. The overall prevalence of HTLV-1 in China decreased from 2016 to 2018. Female was identified as an independent risk factor of HTLV infection in China. Besides, seroconversion was observed in two of seven seroindeterminate donors 85 and 250 days after their last donation, respectively. CONCLUSIONS: The seroprevalence of HTLV infection in most areas of China among blood donors is quite low, but it varies significantly in different geographic areas. Screening anti-HTLV-1/2 antibody and follow-up of serointederminate donors are essential to ensure blood safety especially in areas where we have found HTLV infected donors.

Estimation of the window period of human T-cell leukemia virus type 1 and 2 tests by a lookback study of seroconverters among Japanese voluntary blood donors.

BACKGROUND: Japan is endemic for human T-cell leukemia virus type 1 (HTLV-1), and the horizontal transmission of HTLV-1 is often reported. However, the window period (WP) for serologic or molecular screening is unclear. STUDY DESIGN AND METHODS: Results for anti-HTLV-1 screening and confirmatory tests obtained from 648 591 repeated blood donors in the Kyushu district, one of the most endemic areas of HTLV-1 in the world, were evaluated. A lookback study was conducted for seroconverters. RESULTS: During 2012 to 2019, 436 seroconverters (155 men, 281women) were identified with use of a screening chemiluminescence enzyme-immunoassay (CLEIA) and multiple confirmatory tests. Because the period between the latest seronegative donation and seroconversion was highly variable (2.1-276.7 months), 19 cases that seroconverted within 6 months were subjected to the analysis. The WP of the particle agglutination assay and CLEIA was estimated to be 2.2 ± 0.6 and 2.6 ± 1.7 months, respectively. The WP of the indirect immunofluorescence assay was 4.8 ± 6.5 months. Although the WP of western blotting was estimated to be 6.3 ± 8.7 months, four cases were still indeterminate through the study period. Chemiluminescence and line immunoassays, the current screening and confirmatory tests used in the Japanese blood program, showed the shortest WP of 2.2 ± 0.6 months. The WP of real-time polymerase chain reaction for HTLV-1 was estimated to be 4.1 ± 7.8 months. CONCLUSIONS: The WP in commercially available testing systems for HTLV-1/2 was determined for natural infection among repeated blood donors. Considering the HTLV-1 WP will help increase transfusion safety and facilitate the accurate diagnosis of HTLV-1 infection.

The prevalence of human T-cell leukemia virus in blood donors in China.

BACKGROUND: China has not yet incorporated routine human T-lymphotropic virus (HTLV)-1/2 blood donor screening, even though HTLV has been reported in the southeastern coastal region. This study was conducted to investigate the prevalence of HTLV in five major regions across of China. METHODS: From January 2016 to December 2017, blood samples were collected in 20 blood centers located in different regions of China. These samples were screened for HTLV-1/2 antibodies using enzyme-linked immunosorbent assay (ELISA). If the test samples were reactive, the samples were confirmed with a western blot (WB) assay. If the results of WB were indeterminate, the donor was interviewed after a minimum lapse of 8 weeks. All follow-up samples from donors were tested for anti-HTLV-1/2 with ELISA and WB. RESULTS: There were 875,453 donor samples tested for anti-HTLV-1/2 by ELISA. In all, 365 samples tested negative, 22 samples tested positive by WB, and 14 samples with HTLV status undetermined due to being lost to follow-up. The prevalences were 11.09, 5.96, 3.16, 2.88 and 0.98 per 100,000 in Xiamen, Changsha, Beijing, Shenzhen, and Nanjing blood center, respectively. The prevalences were 0 per 100,000 for all 15 other blood centers. There was significant differences in the prevalence of HTLV in different regions of China (p = 0.0011). CONCLUSION: In China, HTLV-1 confirmed positive donors are mainly from southeastern coastal areas. It may be necessary to conduct HTLV screening in these areas to reduce the risk of transfusion-transmitted HTLV.

Primary cutaneous smoldering adult T-cell leukemia/ lymphoma.

HTLV-1 is a virus that is endemic in southwesternJapan and the Caribbean and has been implicatedin the development of ATLL. ATLL, which is anuncommon malignant condition of peripheralT-lymphocytes, is characterized by four clinicalsubtypes, which include acute, lymphomatous,chronic, and smoldering types, that are based onLDH levels, calcium levels, and extent of organinvolvement. We present a 52-year- old woman withpruritic patches with scale on the buttocks and withtender, hyperpigmented macules and papules oftwo-years duration. Histopathologic examinationwas suggestive of mycosis fungoides, laboratoryresults showed HTLV-I and II, and the patient wasdiagnosed with primary cutaneous ATLL. We reviewthe literature on HTLV-1 and ATLL and specifically theprognosis of cutaneous ATLL. The literature suggeststhat a diagnosis of ATLL should be considered amongpatients of Caribbean origin or other endemicareas with skin lesions that suggest a cutaneousT-cell lymphoma, with clinicopathologic features ofmycosis fungoides. Differentiation between ATLLand cutaneous T-cell lymphoma is imperative as theyhave different prognoses and treatment approaches.

TOXOPLASMA AND VIRAL ANTIBODIES AMONG HIV PATIENTS AND INMATES IN CENTRAL JAVA, INDONESIA.

In Indonesia, Toxoplasma and its associations with blood-borne viruses have been poorly studied. In order to study the association between anti-Toxoplasma antibodies and blood-borne viral antibodies, blood samples from 497 participants (375 inmates from four prisons in Central Java, Indonesia and 122 HIV patients at a Voluntary Counseling and Testing Clinic in Surakarta, Indonesia) were tested for serological markers of Toxoplasma, human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), hepatitis D virus (HDV) and human T-lymphotropic virus types I and II (HTLV-1/2). Anti-Toxoplasma IgG and IgM positivity rates were 41.6% and 3.6%, respectively. One point two percent of participants was positive for both anti-Toxoplasma IgG and IgM antibodies. Sixteen point five percent, 11.3%, 2.6% and 2.8% of participants were positive for anti- Toxoplasma IgG combined with anti-HCV antibodies, anti-Toxoplasma IgG combined with anti-HIV antibodies, anti-Toxoplasma IgM combined with anti-HIV antibodes and anti-Toxoplasma IgG combined with both anti-HIV and anti-HCV antibodies, respectively. Anti-Toxoplasma IgM seropositivity was associated with anti-HIV (aOR = 4.3; 95% CI: 1.112-16.204, p = 0.034). Anti-Toxoplasma IgG antibodies were associated with anti-HCV (aOR = 2.8; 95% CI: 1.749-4.538, p < 0.001) and history of injection drug use (aOR = 3.1; 95% CI: 1.905-5.093, p < 0.001). In conclusion, we recommend patients with HIV, HCV infection and injection drug users should be screened for Toxoplasma infection in Indonesia.

Detection of antibodies to human T-cell leukemia virus types 1 and 2 in breast milk from East Asian women.

We investigated the incidence of human T-cell leukemia virus type I (HTLV-1) infection in a total of 17 regions in four countries, including 13 regions in Japan, as well as Korea (Seoul and Busan), China, and Vietnam, by testing breast milk using a particle agglutination assay (PA) and line immunoassay (LIA). Among 266 samples from Japan, 24 (9.0%) were positive on PA and 3 (1.1%) were positive on LIA. Among 50 samples from Seoul, 2 were positive on PA and 1 was positive on LIA. In contrast, all 50 samples from Busan were negative on both tests, suggesting the maldistribution of HTLV-1 infectants in South Korea. The numbers of positive samples were 2/91 on PA and 1/91 on LIA for China and 1/88 on both PA and LIA for Vietnam. In China, one sample with a high probability of HTLV-2 infection was identified by LIA and synthetic peptide enzyme-linked immunosorbent assay (ELISA). We examined HTLV-1 antibody in breast milk samples using commercially available test kits, suggesting the existence of HTLV-1 carriers in endemic areas in Southeast Asia and an HTLV-2 infectant in China. As a part of human ethno-epidemiological research, these results constitute valuable epidemiological data. Further studies on the sensitivity, specificity, and reliability of assays using antibodies to HTLV-1 and 2 in breast milk will be necessary for large-scale epidemiological surveys of HTLV infection.

Trends in the prevalence and distribution of HTLV-1 and HTLV-2 infections in Spain.

BACKGROUND: Although most HTLV infections in Spain have been found in native intravenous drug users carrying HTLV-2, the large immigration flows from Latin America and Sub-Saharan Africa in recent years may have changed the prevalence and distribution of HTLV-1 and HTLV-2 infections, and hypothetically open the opportunity for introducing HTLV-3 or HTLV-4 in Spain. To assess the current seroprevalence of HTLV infection in Spain a national multicenter, cross-sectional, study was conducted in June 2009. RESULTS: A total of 6,460 consecutive outpatients attending 16 hospitals were examined. Overall, 12% were immigrants, and their main origin was Latin America (4.9%), Africa (3.6%) and other European countries (2.8%). Nine individuals were seroreactive for HTLV antibodies (overall prevalence, 0.14%). Evidence of HTLV-1 infection was confirmed by Western blot in 4 subjects (prevalence 0.06%) while HTLV-2 infection was found in 5 (prevalence 0.08%). Infection with HTLV types 1, 2, 3 and 4 was discarded by Western blot and specific PCR assays in another two specimens initially reactive in the enzyme immunoassay. All but one HTLV-1 cases were Latin-Americans while all persons with HTLV-2 infection were native Spaniards. CONCLUSIONS: The overall prevalence of HTLV infections in Spain remains low, with no evidence of HTLV-3 or HTLV-4 infections so far.

Evaluation of a new screening assay for HTLV-1 and -2 antibodies for large-scale use.

Laboratory testing for Human T-lymphotropic Virus type 1 and 2 (HTLV-1 and -2) infections has become routine in blood transfusion, tissue transplantation and clinical diagnoses in many countries worldwide. Screening is usually based on the detection of antibodies to HTLV-1 and/ or -2. The number of commercially available assays is limited, and among them, ELISA tests based on microtiter format are most commonly used. Recently, the new rHTLV-I/II assay (Abbott Laboratories, Abbott Park, IL) was released; this assay was developed for an automatic large-scale screening platform. This assay was evaluated using pre-characterized serum panels and routine samples from the clinical laboratory. The sensitivity was 100% for HTLV-1 and -2 (99/99 and 42/42, respectively, including one sample that was dually reactive, HTLV-1 + 2). To test assay specificity, panels of blood donor sera, specimens from patients with autoimmune diseases and some viral infections were used. False-reactive samples from previous HTLV diagnoses were also included. With these panels, the specificity was 99.4% (619/623). However, the four false-reactive samples all belonged to the group of samples that were previously considered as false-reactive for HTLV-antibodies. All other samples were negative by the rHTLV-I/II assay, and thus 100% specificity was obtained. The 1,412 samples tested in the clinic by this assay in routine use were all negative (100% specificity). Taken together, the overall specificity was 99.8%. The assay was sensitive, specific and appropriate for the large-scale screening of samples for HTLV-1/2 antibodies.

Geographic distribution of human T-lymphotropic virus types 1 and 2 among mothers of newborns tested during neonatal screening, Minas Gerais, Brazil.

OBJECTIVE: To evaluate the geographic distribution of human T-lymphotropic virus types 1 and 2 (HTLV-1/2) in the State of Minas Gerais, Brazil, in puerperal women whose newborns were tested for HTLV-1/2 during neonatal screening, and to overlap seropositivity with social and economic status determinants. METHODS: During September-November 2007, the dry-blood samples taken from newborns on filter paper for routine screening were also tested for maternal IgG anti-HTLV-1/2 antibodies. For reactive samples, the mothers of the newborns had blood drawn to test for these viruses. RESULTS: The study analyzed 55,293 specimens taken from newborns. Of these, 52 (9.4 per 10,000) were reactive and 42 mothers (7.6 per 10,000) were confirmed with HTLV-1/2 infection. HTLV-1/2 geographic distribution was heterogeneous, with a tendency to be higher in the North and North-East parts of Minas Gerais. The highest rates of seropositivity were observed in Vale do Mucuri (55.9 per 10,000) and in Jequitinhonha (16.0 per 10,000), overlapping with the State's worst social and economic indicators. CONCLUSIONS: To our knowledge this was the first time that neonatal screening for HTLV-1/2 was performed in Brazil. This model could be used in other areas with high HTLV-1/2 prevalence rates. The detection of carrier mothers can enable intervention measures, such as providing infant formula to newborns, to be implemented expeditiously to reduce vertical transmission.

[Investigation of anti-HTLV I/II seroprevalence in healthy blood donors in Izmir region, Turkey]. / Izmir bölgesinde saglikli kan vericilerinde anti-HTLV-I/II seroprevalansinin arastirilmasi

Almost 10-20 million people in the world are thought to be infected by human deltaretroviruses, namely human T-cell lymphotropic virus (HTLV) type I and II, recently. HTLV-I is endemic in southwestern Japan, the Caribbean and sub-Saharan Africa, whereas HTLV-II is more prevalent in intravenous drug addicts, and in American indian populations, endemically. HTLV-I is mainly responsible for adult T-cell leukemia (ATL) and HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP), however, HTLVII is not clearly associated with a known clinical disease. Both viruses may be transmitted by sexual contact, parenteral route, whole blood transfusion and breast-feeding. In most of the countries [USA, Canada, South America, Caribbean, Japan, Taiwan and some Europe countries (France, UK, Ireland, Sweden, Denmark, The Netherlands, Portugal, Romania, Greece)] routine screening of anti-HTLV-I/II in blood donors is mandatory, however, there is no such practice in Turkey since seroepidemiologic data on HTLVI/II infections is insufficient. In this study, the seroprevalence of HTLV-I/II in healthy blood donors admitted to the blood bank of Ege University Medical Faculty Hospital, Izmir (located at Aegean region), was investigated to support data on the decision making process on routine screening of anti-HTLV-I/II in blood centers. Serum samples from 10.000 healthy blood donors (mean age: 32.6 years; 87.8% were male), who succeeded the donor history questionnaire, were included to the study, and HTLV-I/II antibodies were screened by a commercial enzyme immunoassay (ELISA) (Murex HTLVI-II, Murex Diagnostics, UK) method. Serum samples which were yielded reactive and borderline results were retested by ELISA, and repeated reactive/borderline results were then confirmed by HTLV-I/II confirmation test (INNO-LIA HTLV-I/II, Innogenetics, Belgium). Seven samples yielded reactive/borderline reactive results by both ELISA lots, however, all of them were found negative by confirmatory test. According to our data HTLV-I/II infections are not endemic in Izmir region, and anti-HTLV-I/II screening of blood donors is not required in our blood center currently. Nevertheless, screening HIV which is very rare in prevalence among the donor population, is mandatory for blood donors in our country. Thus, even its prevalence is very low, much more comprehensive and multi-centered studies are necessary for making the decision of integrating HTLV-I/II in routine blood bank screening tests in Turkey.

Surveillance of human retroviruses in blood samples from patients with hepatitis B and C in São Paulo, Brazil.

INTRODUCTION: Human retroviruses and the hepatitis B and C viruses (HBV and HCV, respectively) share routes of transmission; thus, coinfections occur and could alter subsequent disease outcomes. A preliminary study on human T-lymphotropic virus types 1 and 2 (HTLV-1/2) in serum samples from HBV- and HCV-infected individuals in São Paulo revealed 1.3% and 5.3% rates of coinfection, respectively. These percentages were of concern since they were detected in HTLV-endemic regions and in high-risk individuals in Brazil. The present study was conducted to extend and confirm these data. METHODS: HTLV-1/2 and human immunodeficiency virus (HIV) infection status were identified in 1,984 sera for HBV and HCV viral load quantification - 1,290 samples from HBV-infected individuals (53.3% men, mean age: 47.1 years) and 694 samples from HCV-infected individuals (56.3% men, mean age: 50.1 years). HTLV-1/2 antibodies were detected by enzyme immunoassay, followed by western blotting and line immunoassay; HIV infection was detected by enzyme immunoassay. RESULTS: HTLV-1/-2 infection was detected in 1.9% HBV-infected individuals (0.7% HTLV-1 and 1.2% HTLV-2) and in 4.0% (2.4% HTLV-1 and 1.6% HTLV-2) HCV-infected individuals; HIV infection was detected in 9.2% and 14.5%, respectively. Strong associations with HTLV and HIV, male sex, and older age were found in HBV/HTLV and HCV/HTLV-coinfected individuals (p<0.05). CONCLUSIONS: HTLV-1 and HTLV-2 were confirmed to be prevalent in individuals with HBV and HCV in São Paulo; coinfected individuals deserve further clinical and laboratory investigation.

Epidemiology of human T-cell lymphotropic virus type 1 infection in blood donors, Israel.

The prevalence of infection with human T-cell lymphotropic virus type 1 (HTLV-1) in blood donors from Israel is 1 infection/100,000 persons. In donors originating from Eastern Europe, the Middle East, and Latin America, prevalences are 7.7, 14.6, and 20.4, respectively. HTLV-1 prevalence may be high outside areas where HTLV-1 previously was known to be endemic.

High rate of HTLV-II infection in seropositive i.v. drug abusers in New Orleans.

Confirmed infection with HTLV-II (human T cell leukemia virus type II) has been described only in rare cases. The major limitation to serological diagnosis of HTLV-II has been the difficulty of distinguishing HTLV-II from HTLV-I (human T cell leukemia virus type I) infection, because of substantial cross-reactivity between the viruses. A sensitive modification of the polymerase chain reaction method was used to provide unambiguous molecular evidence that a significant proportion of intravenous drug abusers are infected with HTLV, and the majority of these individuals are infected with HTLV-II rather than HTLV-I. Of 23 individuals confirmed by polymerase chain reaction analysis to be infected with HTLV, 21 were identified to be infected with HTLV-II, and 2 were infected with HTLV-I. Molecular identification of an HTLV-II--infected population provides an opportunity to investigate the pathogenicity of HTLV-II in humans.

Seroprevalence of human T lymphtropic virus (HTLV) among tissue donors in Iranian tissue bank.

Iranian Tissue Bank prepares a wide range of human tissue homografts such as; heart valve, bone, skin, amniotic membrane and other tissues for different clinical applications. The purpose of this study was to determine the seroprevalence of HTLV in tissue donors. About 1,548 tissue donors were studied during a 5-years period by ELISA assays. HTLV(1,2)-antibodies were tested for all of donors with other tests upon American Association of Tissue Banks (AATB) standards. About 25 (1.61%) out of 1,548 tissue donors were HTLV positive that 17 donors were male and 8 were female (female/male ratio was approximately 47%). Regarding to the prevalence of HTLV among tissue donors and importance of cell and tissue safety and quality assurance, we recommend that all blood, cell and tissue banks should be involved both routine serological methods and other complementary tests such as polymerase chain reaction (PCR) for diagnosis of HTLV.

Seroprevalence of HTLV-1/2 Among Voluntary Blood Donors in Vietnam.

Infection with human T lymphotropic virus (HTLV), although asymptomatic in most cases, can lead to severe illnesses, such as adult T cell leukemia/lymphoma or myelopathy/tropical spastic paraparesis. HTLV can be transmitted by whole-blood (WB) transfusion. The prevalence of HTLV among blood donor populations has not been characterized in Vietnam, although the screening has been partially implemented on voluntary basis since 2016. To determine the seroprevalence of HTLV-1/2 among blood donors, a total of 14,819 healthy blood donors in northern, central, and southern Vietnam and 1,003 samples from hepatitis B surface antigen (HbsAg), anti-hepatitis C (anti-HCV), or HIV Ag/Ab reactive blood donors were screened for anti-HTLV-1/2 antibodies by a chemiluminescence immunoassay using the Abbott ARCHITECT rHTLV-I/II assay. The anti-HTLV-1/2 repeat reactive (RR) samples were further tested by immunoblot (IB) method using MP Biomedicals HTLV Blot 2.4 for confirmation and differentiation of HTLV-1/2 infection. Proviral HTLV subgenomic amplification of the gag and tax regions was performed on the available WB RR samples (N = 11) by polymerase chain reaction (PCR). Among 14,819 blood donors, 34 samples (0.23%) were RR for anti-HTLV-1/2 antibodies, but only 1 case was confirmed HTLV-2 positive (0.0067%) and 5 cases were classified as indeterminate (0.034%) by IB. The RR rate was 0.39% among HBsAg/anti-HCV/HIV reactive sample groups, but none of them was confirmed by IB. Subgenomic PCR failed to amplify proviral DNA from WB samples of 11 RR samples. HTLV-1/2 prevalence was found to be low among blood donors in the study. Continued vigilance remains essential to maintain a low transfusion-transmitted risk in Vietnam.

Seroprevalence of human T-lymphotropic virus type 1 and 2 in Korean blood donors.

The seroprevalence rate of human T-lymphotropic virus (HTLV) among the Korean blood donor population was studied to determine whether screening for HTLV should be implemented. A total of 15,173 serum samples collected from June to July 2006 at five Blood Centers which are located closely to Japan geographically, where the prevalence of HTLV is known to be high, were tested. Serological screening was done by a chemiluminescence method. Samples reactive repeatedly on serological screening were confirmed further by Western blot, line immunoassay, nested polymerase chain reaction and sequencing of proviral DNA. Six samples tested reactive with the serological assay showing a reactive rate of 0.004%. Among the six samples, one sample was confirmed as HTLV-1 positive, giving a confirmed reactive rate of 0.007%. Based on the results of this study, an extended study will be conducted to evaluate whether introduction of HTLV screening is necessary in Korea.

Serological patterns and temporal trends of HTLV-1/2 infection in high-risk populations attending Public Health Units in São Paulo, Brazil.

BACKGROUND: HTLV-1/2 diagnosis in high-risk populations from São Paulo, Brazil has been problematic due a high proportion of seroindeterminate results. OBJECTIVES: To confirm and extend previous findings regarding HTLV-1/2 diagnosis in this geographic area. STUDY DESIGN: Sera from 2312 patients were tested for HTLV-1/2 antibodies using enzyme immunoassay (EIA) and Western blot (WB) analysis. Patients were from AIDS Reference Centers (Group I; 1393 patients) and HTLV out-patient clinics (Group II; 919 patients). Results were analyzed according to patients' age, gender, and clinic type. RESULTS: HTLV-1 and HTLV-2 were detected in both groups. Among seropositive females, HTLV-2 was slightly more common in Group I (54.5%), while HTLV-1 prevailed in Group II (73.9%). Males from Group II had a higher percentage of HTLV-seroindeterminate results. No correlation between HTLV serological results and age was detected. Temporal analyses disclosed a high number of HTLV-seroindeterminate samples, and a large spectrum of indeterminate WB profiles. GD21 and/or rgp46-II bands were detected in 34.6% of sera from Group I, and a p24 or p19 band was detected in 35.3% of sera from Group II. CONCLUSIONS: High rates of HTLV-indeterminate serological patterns during temporal analyses were confirmed in high-risk populations from São Paulo, Brazil.

Comparison of four commercial screening assays for the diagnosis of human T-cell lymphotropic virus types 1 and 2.

Serological assays for human T-cell lymphotropic virus types 1 and 2 (HTLV-1/2) are widely used in routine screening of blood donors. The aim of this study was to compare the performance of four commercial screening assays for HTLV-1/2 infection frequently used in South America. A total of 142 HTLV-1 and HTLV-2 seropositive and 336 seronegative samples were analyzed by using four commercial tests (BioKit, Vironostika, Murex and Fujirebio). These tests are commonly used for HTLV-1/2 detection in blood banks in Argentina. A nested-PCR was used as the reference standard. The most sensitive tests for HTLV-1/2 were Fujirebio and Biokit (98.6%) followed by Murex (97.2%) and Vironostika (96.5%). The most specific test was Murex (99.7%), followed by Biokit (97.0%), Fujirebio (95.8%), and Vironostika (92.9%). The kappa index of agreement was higher for Murex (kappa=0.97), followed by BioKit (kappa=0.94), Fujirebio (kappa=0.92), and Vironostika (kappa=0.86). The highest index of agreement was shown by Murex test while Vironostika had the lowest performance. Of the four tests evaluated, only the Vironostika assay is approved by the Food and Drug Administration. These results should be considered for choosing the most accurate serological screening assays in order to obtain an optimal efficiency of the current algorithm for HTLV-1/2 diagnosis.

[HTLV 1/2 infection: prenatal performance as a disease control strategy in State of Mato Grosso do Sul]. / Infecção pelo HTLV 1/2: atuação no pré-natal como estratégia de controle da doença no Estado de 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.