Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Brazil.
Faculdade de Medicina, Instituto de Ciências da Saúde, Universidade Federal do Pará, Belém, Brazil.
Front Public Health. 2022 Feb 11;10:833169. doi: 10.3389/fpubh.2022.833169. eCollection 2022.
Human T-lymphotropic virus (HTLV) infection is endemic in indigenous populations of the Americas. We describe herein the prevalence of HTLV-1 and HTLV-2 infection among Warao indigenous refugees from Venezuela living in Belém, Pará, Brazil.
In total, 101 individuals of both sexes (43 men and 58 women) between 18 and 77 years of age were investigated. Blood samples were collected and separated into plasma and leukocytes. Serological screening was performed using an enzyme-linked immunosorbent assay (ELISA; Murex HTLV-I+II, DiaSorin, Dartford, UK), and seropositive samples were submitted to proviral DNA extraction followed by real-time polymerase chain reaction (qPCR). A nested PCR of the region (630 bp) followed by enzymatic digestion with I was performed to identify the molecular subtype of HTLV-2, in addition to sequencing analysis of the 5'LTR-I and 5'-LTR-II regions.
Of the 101 individuals analyzed, 3 (3.0%) were seropositive. Molecular analysis of the and genes confirmed the HTLV-1 infection in a 55-year-old woman and HTLV-2 infection in a man (68 years old) and a woman (23 years old). HTLV-2 strains were defined by enzymatic digestion as belonging to the HTLV-2b subtype. The sequencing of the 5'LTR regions confirmed the presence of subtype 2b and identified HTLV-1 as belonging to subtype 1A (Cosmopolitan) and the Transcontinental subgroup. Among the infected patients, it was possible to conduct medical interviews with two individuals after delivery of the result. One patient with HTLV-2 reported symptoms such as joint pain, foot swelling, frequent headache, dizziness and lower back pain. The HTLV-1-positive woman was diagnosed with a tumor, dementia, urinary incontinence, felt body pain, and had spots on her body. The presence of the HTLV-2b subtype highlights the prevalence of this molecular variant among indigenous South Americans, as well as the presence of HTLV-1 Transcontinental, which has a worldwide distribution.
These results reveal a high prevalence of HTLV-1/2 infection among Warao immigrants, suggesting migratory flow as a virus spread mechanism among human populations and alert public authorities to the need to create epidemiological surveillance programs, public social and health policies aimed at welcoming immigrants in the Brazilian territory.
人类 T 淋巴细胞病毒（HTLV）感染在美洲的土著人群中流行。我们在此描述了居住在巴西帕拉州贝伦的委内瑞拉瓦劳土著难民中 HTLV-1 和 HTLV-2 感染的流行情况。
共调查了 101 名 18 至 77 岁的男女（男 43 名，女 58 名）。采集血样并分离出血浆和白细胞。采用酶联免疫吸附试验（ELISA；Murex HTLV-I+II，DiaSorin，达特福德，英国）进行血清学筛查，对血清阳性样本进行前病毒 DNA 提取，然后进行实时聚合酶链反应（qPCR）。进行 HTLV-2 的 区（630 bp）巢式 PCR，然后用 I 进行酶切，以鉴定 HTLV-2 的分子亚型，此外还对 5'LTR-I 和 5'-LTR-II 区进行测序分析。
在分析的 101 个人中，有 3 人（3.0%）血清阳性。对 和 基因的分子分析证实，一名 55 岁的女性感染了 HTLV-1，一名 68 岁的男性和一名 23 岁的女性感染了 HTLV-2。酶切鉴定 HTLV-2 株属于 HTLV-2b 亚型。5'LTR 区的测序证实存在 2b 亚型，并确定 HTLV-1 属于 1A（世界性）和 Transcontinental 亚群。在感染患者中，有 2 名患者在结果出来后可以进行医疗访谈。一名 HTLV-2 患者报告了关节痛、脚肿、频繁头痛、头晕和腰痛等症状。HTLV-1 阳性的女性被诊断出患有肿瘤、痴呆、尿失禁、身体疼痛和身上有斑点。HTLV-2b 亚型的存在突出了该分子变体在南美土著人群中的流行，以及 HTLV-1 Transcontinental 的存在，该变体在全球范围内传播。
这些结果表明，瓦劳移民中 HTLV-1/2 感染的流行率很高，这表明病毒在人群中的传播机制是移民流动，并提醒公共当局有必要建立针对巴西领土移民的流行病学监测计划、公共社会和卫生政策。
