Brazilian HTLV type 2a strains from intravenous drug users (IDUs) appear to have originated from two sources: Brazilian Amerindians and European/North American IDUs

In Brazil, HTLV-2 has been detected in blood donors, in intravenous drug users (IDUs) from urban areas, and in Amerindians living in the Amazon basin. Of the three main HTLV-2 subtypes (2a, 2b, and 2d) only subtype 2a has been detected in Brazil. However, a molecular variant of subtype 2a (also called HTLV-2c) characterized by an extended Tax protein has been isolated from Brazilian blood donors, IDUs, and Indians. Here, we analyzed HTLV-2 isolates from 10 IDUs and a Chilean woman living in Salvador, Bahia, Brazil. Sequencing of env, pX, and long terminal repeat (LTR) genes demonstrated that 10 of the isolates are related to the Brazilian subtype 2a molecular variant described previously. We show that most HTLV-2a Brazilian strains comprise a phylogenetic group harboring a considerable degree of diversity within the env region but not within the LTR region. Interestingly, we demonstrated for the first time in Brazil the presence of a subtype 2a in IDUs that is closely related to the prototype Mo but distinct from the Brazilian 2a molecular variant.status: publishe

Human retroviruses (HIV and HTLV) in Brazilian Indians: seroepidemiological study and molecular epidemiology of HTLV type 2 isolates

To investigate serological, epidemiological, and molecular aspects of HTLV-1, HTLV-2, and HIV-1 infections in Amerindian populations in Brazil, we tested 683 and 321 sera from Tiriyo and Waiampi Indians, respectively. Both HIV-1 and HTLV-2 infections were detected at low prevalence among the Tiriyos whereas only HTLV-1 was present among the Waiampis, also at low prevalence. Analysis of the nucleotide sequence of the 631 bp of the env gene obtained from the three HTLV-2 isolates detected among the Tiriyos demonstrated by restriction fragment length polymorphism that these viruses belong to subtype IIa. Phylogenetic analysis of this same fragment showed that these sequences cluster closer to HTLV-2 isolates from intravenous drug users living in urban areas of southern Brazil than to the same gene sequence studied in another Brazilian tribe, the Kayapos. Our results confirm the distribution of Brazilian HTLV-2 sequences in a unique cluster I and cluster IIa and suggest that there is a considerable degree of diversity within this cluster. We also report for the first time HIV-1 infection among Brazilian Amerindians.status: publishe

HTLV in the Americas: challenges and perspectives.

The first description of the human T-lymphotropic virus type 1 (HTLV-1) was made in 1980, followed closely by the discovery of HTLV-2, in 1982. Since then, the main characteristics of these viruses, commonly referred to as HTLV-1/2, have been thoroughly studied. Central and South America and the Caribbean are areas of high prevalence of HTLV-1 and HTVL-2 and have clusters of infected people. The major modes of transmission have been through sexual contact, blood, and mother to child via breast-feeding. HTLV-1 is associated with adult T-cell leukemia/lymphoma (ATL), HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP), and HTLV-associated uveitis as well as infectious dermatitis of children. More clarification is needed in the possible role of HTLV in rheumatologic, psychiatric, and infectious diseases. Since cures for ATL and HAM/TSP are lacking and no vaccine is available to prevent HTLV-1 and HTLV-2 transmission, these illnesses impose enormous social and financial costs on infected individuals, their families, and health care systems. For this reason, public health interventions aimed at counseling and educating high-risk individuals and populations are of vital importance. In the Americas this is especially important in the areas of high prevalence

Epidemiology and evolution of Zika virus in Minas Gerais, Southeast Brazil

Autochthonous Zika virus (ZIKV) transmission in Brazil was first identified in April 2015 in Brazil, with the first ZIKV-associated microcephaly cases detected in October 2015. Despite efforts on understanding ZIKV transmission in Brazil, little is known about the virus epidemiology and genetic diversity in Minas Gerais (MG), the second most populous state in the country. We report molecular and genomic findings from the main public health laboratory in MG. Until January 2020, 26,817 ZIKV suspected infections and 86 congenital syndrome cases were reported in MG state. We tested 8552 ZIKV and microcephaly suspected cases. Ten genomes were generated on-site directly from clinical samples. A total of 1723 confirmed cases were detected in Minas Gerais, with two main epidemic waves; the first and larger epidemic wave peaked in March 2016, with the second smaller wave that peaked in March 2017. Dated molecular clock analysis revealed that multiple introductions occurred in Minas Gerais between 2014 and 2015, suggesting that the virus was circulating unnoticed for at least 16 months before the first confirmed laboratory case that we retrospectively identified in December 2015. Our findings highlight the importance of continued genomic surveillance strategies combined with traditional epidemiology to assist public health laboratories in monitoring and understanding the diversity of circulating arboviruses, which might help attenuate the public health impact of infectious diseases

A computational method for the identification of Dengue, Zika and Chikungunya virus species and genotypes

In recent years, an increasing number of outbreaks of Dengue, Chikungunya and Zika viruses have been reported in Asia and the Americas. Monitoring virus genotype diversity is crucial to understand the emergence and spread of outbreaks, both aspects that are vital to develop effective prevention and treatment strategies. Hence, we developed an efficient method to classify virus sequences with respect to their species and sub-species (i.e. serotype and/or genotype). This tool provides an easy-to-use software implementation of this new method and was validated on a large dataset assessing the classification performance with respect to whole-genome sequences and partial-genome sequences. Available online: http://krisp.org.za/tools.php.status: publishe

RegaDB: community-driven data management and analysis for infectious diseases

SUMMARY: RegaDB is a free and open source data management and analysis environment for infectious diseases. RegaDB allows clinicians to store, manage and analyse patient data, including viral genetic sequences. Moreover, RegaDB provides researchers with a mechanism to collect data in a uniform format and offers them a canvas to make newly developed bioinformatics tools available to clinicians and virologists through a user friendly interface.Availability and implementation: Source code, binaries and documentation are available on http://rega.kuleuven.be/cev/regadb. RegaDB is written in the Java programming language, using a web-service-oriented architecture. CONTACT: [email protected]: publishe