Vertical transmission of HTLV-I/II: a review

Viruses and Human Milk: Transmission or Protection?

Human milk (HM) is considered the best source of nutrition for infant growth and health. This nourishment is unique and changes constantly during lactation to adapt to the physiological needs of the developing infant. It is also recognized as a potential route of transmission of some viral pathogens although the presence of a virus in HM rarely leads to a disease in an infant. This intriguing paradox can be explained by considering the intrinsic antiviral properties of HM. In this comprehensive and schematically presented review, we have described what viruses have been detected in HM so far and what their potential transmission risk through breastfeeding is. We have provided a description of all the antiviral compounds of HM, along with an analysis of their demonstrated and hypothesized mechanisms of action. Finally, we have also analyzed the impact of HM pasteurization and storage methods on the detection and transmission of viruses, and on the antiviral compounds of HM. We have highlighted that there is currently a deep knowledge on the potential transmission of viral pathogens through breastfeeding and on the antiviral properties of HM. The current evidence suggests that, in most cases, it is unnecessarily to deprive an infant of this high-quality nourishment and that the continuation of breastfeeding is in the best interest of the infant and the mother.

A Review of the Prevention of Mother-to-Child Transmission of Human T-Cell Lymphotrophic Virus Type 1 (HTLV-1) With a Proposed Management Algorithm

Human T cell lymphotropic virus type 1 (HTLV-1) is a human retrovirus that is endemic in a number of regions across the world. There are an estimated 5–10 million people infected worldwide. Japan is currently the only country with a national antenatal screening programme in place. HTLV-1 is primarily transmitted sexually in adulthood, however it can be transmitted from mother-to-child perinatally. This can occur transplacentally, during the birth process or via breastmilk. If HTLV-1 is transmitted perinatally then the lifetime risk of adult T cell leukemia/lymphoma rises from 5 to 20%, therefore prevention of mother-to-child transmission of HTLV-1 is a public health priority. There are reliable immunological and molecular tests available for HTLV-1 diagnosis during pregnancy and screening should be considered on a country by country basis. Further research on best management is needed particularly for pregnancies in women with high HTLV-1 viral load. A first step would be to establish an international registry of cases and to monitor outcomes for neonates and mothers. We have summarized key risk factors for mother-to-child transmission of HTLV-1 and subsequently propose a pragmatic guideline for management of mothers and infants in pregnancy and the perinatal period to reduce the risk of transmission. This is clinically relevant in order to reduce mother-to-child transmission of HTLV-1 and it's complications.

Breastfeeding With Infectious Diseases

Aims: Human breast milk remains an important source of protection against infection, inflammation, allergy and long-term metabolic disorders for the breastfed offspring. During cases of ongoing infection, the dilemma faced by both medical health professionals and mothers is the need to balance the risk of continuing versus temporarily or permanently ceasing to breastfeed. The aim of our article is to review existing literature regarding breastfeeding during acute infectious and non-infectious illnesses and to provide feasible evidence-based suggestions which can be implemented by medical practitioners during counselling of breastfeeding mothers.

Method: A literature search was conducted on PubMed (US National Library of Medicine) using various combinations of keywords related to breastfeeding and the various infections. The citations from all selected articles were reviewed for additional studies.

Results: Most ongoing infections are not contraindications for breastfeeding, with the exceptions of Human Immunodeficiency viruses (HIV), Human T-cell lymphotropic virus (HTLV) types 1 and 2. Even with HIV, there is increasing evidence to reassure that with adequate antiretroviral therapy, breastfeeding is likely to be safe. Of particular concern during the COVID-19 pandemic too, current evidence indicates that mothers with COVID-19 infection can safely breastfeed, and therefore initiation and continuation of breastfeeding should continue to protect the health of the babies and mothers.

Conclusion: During this pandemic especially, there is a strong and urgent need to support mothers with acute infections who wish to breastfeed. With better awareness, physicians can play an important role in securing positive experiences for breastfeeding mothers and optimizing infant outcomes.

From Ancient to Emerging Infections: The Odyssey of Viruses in the Male Genital Tract

The male genital tract (MGT) is the target of a number of viral infections that can have deleterious consequences at the individual, offspring, and population levels. These consequences include infertility, cancers of male organs, transmission to the embryo/fetal development abnormalities, and sexual dissemination of major viral pathogens such as human immunodeficiency virus (HIV) and hepatitis B virus. Lately, two emerging viruses, Zika and Ebola, have additionally revealed that the human MGT can constitute a reservoir for viruses cleared from peripheral circulation by the immune system, leading to their sexual transmission by cured men. This represents a concern for future epidemics and further underlines the need for a better understanding of the interplay between viruses and the MGT. We review here how viruses, from ancient viruses that integrated the germline during evolution through old viruses (e.g., papillomaviruses originating from Neanderthals) and more modern sexually transmitted infections (e.g., simian zoonotic HIV) to emerging viruses (e.g., Ebola and Zika) take advantage of genital tract colonization for horizontal dissemination, viral persistence, vertical transmission, and endogenization. The MGT immune responses to viruses and the impact of these infections are discussed. We summarize the latest data regarding the sources of viruses in semen and the complex role of this body fluid in sexual transmission. Finally, we introduce key animal findings that are relevant for our understanding of viral infection and persistence in the human MGT and suggest future research directions.

Emerging sexually transmitted viral infections: Review of human T-lymphotropic virus-1 disease

Human T-lymphotropic virus-1 is a preventable sexually transmitted infection. In the majority of people it is asymptomatic, remaining undiagnosed and thereby contributing to its silent transmission. When it does manifest it causes significant morbidity and mortality. This review summarises the existing evidence for its role in sexual transmission and offers suggestions for those working in the area of sexual health. This is the third part of a series looking at novel sexually transmitted infections.

HTLV: a stigmatizing infection?

HTLV is a virus that affects human T-cells. Brazil is the country of the world with the largest absolute number of HTLV cases. Estimates by the Ministry of Health point to 700,000 to 2 million infected Brazilians. The majority are asymptomatic carriers, but some persons may develop degenerative neurological conditions such as tropical spastic paraparesis, in addition to leukemia and lymphoma. The forms of transmission and clinical manifestations such as progressive motor incapacity, genitourinary disorders, in addition to restriction of maternal breastfeeding, impact daily life and can lead to social discrimination and stigma. The stigma denotes violation of social norms and reinforces prejudice and inequalities. This article aims to discuss the concept of stigma and its repercussions on persons living with HTLV. The discussion is based on a literature review on the theme and the authors' experience with care for persons affected by the infection and illness. The study found that both HTLV carrier status and HTLV-related illness can be stigmatizing for individuals, who feel inferior for being infected with a potentially serious and even fatal disease, although incompletely understood and loaded with derogatory stereotypes. This situation can have negative repercussions on access to health services, treatment adherence, and pursuit of rights. Public policies should help mitigate such stigmatization, ensuring the rights of individuals in a situation of vulnerability due to HTLV in order from them to live as protagonists in the exercise of their civil rights.

HTLV-1 is predominantly sexually transmitted in Salvador, the city with the highest HTLV-1 prevalence in Brazil

Background

Salvador is the city with the highest number of HTLV-1 infected individuals in Brazil, yet the main route of HTLV-1 transmission is unknown.

Objective

To investigate the association of syphilis infection as a proxy for sexual transmission of HTLV-1 infection in the general population of this city.

Methods

A cross sectional population-based study was conducted with 3,451 serum samples obtained by a representative simple random sampling. Data on gender, age, income, and years of education were collected by questionnaire and the presence of HTLV, HIV and Treponema pallidum infection was determined by serology. Logistic regression analysis was used to evaluate the independent effect of the potential explanatory variables to HTLV-1 infection and Odds Ratios (OR) and 95% CI were calculated.

Results

The majority of studied individuals were female (56.4%), had less than 7 years of education (55.3%) and earned two or less minimum wages (52.0%). The overall prevalence of HTLV-1 was 1.48% (51/3,451; 95% CI: 1.10%– 1.94%), which increased with age. Only three persons younger than 17 (3/958; 0.31%; CI 95% 0.06–0.91) years were infected by HTLV-1. Among the 45 syphilis positives, 12 (26.7%) were HTLV positive, while among 21 HIV positives, only one (4.8%) was HTLV positive. HTLV-1 infection was found to be associated with syphilis infection (OR_ADJUSTED 36.77; 95% CI 14.96–90.41).

Conclusion

The data presented herein indicate that horizontal transmission between adults is the main route of HTLV-1 infection in the general population of Salvador and that this is likely to occur through sexual contact.

Inflammatory manifestations of HTLV-1 and their therapeutic options

Human T lymphotropic virus type 1 (HTLV-1) is one of the most intriguing retroviruses infecting humans. Most commonly, infection remains undetected, since it does not cause obvious harm, yet in 4-9% of patients, this infection can be devastating, causing adult T-cell leukemia/lymphoma and/or HTLV-1 associated myelopathy/tropical spastic paraparesis (HAM/TSP). This review concentrates on all inflammatory aspects of HTLV-1 infection: HAM/TSP, HTLV-1 associated uveitis, HTLV-1 associated conjunctivitis, sicca syndrome and interstitial keratitis, HTLV-1 associated Sjögren's syndrome, Hashimoto's thyroiditis and Graves' disease, HTLV-1 associated pulmonary disease, infective dermatitis associated with HTLV-1, HTLV-1 associated inflammatory myositis and HTLV-1 associated arthritis. With the exception of HAM/TSP treatment, studies of these conditions are sparse and even for HAM/TSP, the level of evidence is limited. While control or elimination of infection remains a goal, most therapy beyond symptomatic management is directed at the immune response to HTLV-1.

Seroprevalence of HTLV-1/2 among blood donors in the state of Maranhão, Brazil

BACKGROUND

Infection with human T-lymphotropic virus 1 or 2 (HTLV-1/2) is a major health problem. There is a public health policy defining measures for state hematology and hemotherapy centers in Brazil, in order to avoid virus transmission through blood donors.

OBJECTIVE

This study aimed to evaluate the seroprevalence of HTLV -1/2 in blood donors in the State of Maranhão, Brazil, during routine blood unit screening.

METHODS

Screening tests of blood donors using the enzyme-linked immunosorbent assay (ELISA) to detect seropositivity for HTLV-1/2 performed at the Hematology and Hemotherapy Center of the State of Maranhão (HEMOMAR) between July of 2003 and December of 2009 were retrospectively evaluated.

RESULTS

Of the 365,564 blood donors, 561 (0.15%) were HTLV-1/2-positive, of whom 72 (12.8%) performed the confirmatory test (Western blot). In donors who had a confirmatory test, 53 (73.6%) were positive. The ages of the infected individuals ranged from 18 to 65 years; 305 (54%) were aged over 40 years. Among the infected individuals, 309 (55%) were male, 399 (71%) were mixed-race, and 259 (46%) were single. Co-infections were frequently found, especially with hepatitis B (in 68.6% of the cases).

CONCLUSION

The results obtained will contribute to the planning and implementation of control measures by the epidemiological surveillance agency of Maranhão, and will also contribute to reducing morbidity. The high seropositivity in a small sample in donors who had confirmatory tests indicates the need for confirmatory tests for all donors who initially test as seropositive.

Immunopathogenesis and neurological manifestations associated to HTLV-1 infection

The human T lymphotropic virus type-1 (HTLV-1) was the first human retrovirus identified. The virus is transmitted through sexual intercourse, blood transfusion, sharing of contaminated needles or syringes and from mother to child, mainly through breastfeeding. In addition to the well-known association between HTLV-1 and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), several diseases and neurologic manifestations have been associated with the virus. This review was conducted through a PubMed search of the terms HTLV-1, immune response and neurological diseases. Emphasis was given to the most recent data regarding pathogenesis and clinical manifestations of HTLV-1 infection. The aim of the review is to analyze the immune response and the variety of neurological manifestations associated to HTLV-1 infection. A total of 102 articles were reviewed. The literature shows that a large percentage of HTLV-1 infected individuals have others neurological symptoms than HAM/TSP. Increased understanding of these numerous others clinical manifestations associated to the virus than adult T cell leukemia/lymphoma (ATLL) and HAM/TSP has challenged the view that HTLV-1 is a low morbidity infection.

High prevalence of HTLV-1 and 2 viruses in pregnant women in São Luis, state of Maranhão, Brazil

INTRODUCTION

Human T cell lymphotropic virus type 1 (HTLV-1) is endemic in the Caribbean, Japan, South America and regions of Africa. HTLV-2 is present in Native American populations and associated with IV drug use in Europe and North America. In Brazil, it is estimated that 1.5 million people are infected with HTLV-1/2. The study objective was to determine HTLV-1/2 prevalence in pregnant women in the prenatal care from three public services in São Luis, State of Maranhão, Brazil, and to counsel seropositive women to reduce viral transmission.

METHODS

A cross-sectional study was conducted from February to December 2008; women with age of 18 to 45 years, with low risk for sexually transmitted disease (STD) were invited to participate. Blood samples were collected in filter paper, and HTLV-1/2 immunoenzymatic test (ELISA) was performed as a screening test. Women with reactive results were submitted to peripheral venous blood collection for ELISA repetition, followed by Western blot (WB) and real-time PCR to confirm and discriminate the infection between virus types 1 and 2.

RESULTS

Of the 2,044 women tested, seven (0.3%) were ELISA reactive and confirmed positive (four were HTLV-1, and three were HTLV-2). All positive women were oriented not to breastfeed their newborns.

CONCLUSIONS

This study showed that the virus is present in high prevalence in that population. Further studies covering other segments of the population are necessary to better characterize the presence of HTLV-1/2 in Maranhão and to elicit measures to prevent its spread.

Infective dermatitis associated with human T-cell lymphotropic virus type 1: evaluation of 42 cases observed in Bahia, Brazil

BACKGROUND

Infective dermatitis associated with human T-cell lymphotropic virus type 1 (HTLV-1; IDH) is a chronic recurrent eczema affecting HTLV-1-infected children. The epidemiological and dermatological characteristics of IDH are described, and their principal diagnostic criteria are reevaluated.

METHODS

Forty-two patients were included: 40 patients serologically positive for HTLV-1 and 2 seronegative patients who tested positive in polymerase chain reaction (PCR) assays.

RESULTS

The mean age at onset of the disease was 2.6 ± 2.4 years (range, 2 months-11 years). The mean duration of breast-feeding was 24.2 months. The lesions were erythematous, scaly, and crusted, always affecting the scalp and retroauricular regions. Crusting of the nostrils was observed in 64.3% of the patients. Of the 36 patients followed up, 23 had the active disease. The age at which IDH disappeared in the others was 10-20 years.

CONCLUSIONS

The onset of IDH may occur earlier than reported in the literature. The scalp and retroauricular regions are always affected, and lesions are invariably present in ≥3 areas. Crusting of the nostrils cannot be considered an obligatory factor for the diagnosis of IDH. The recurring nature of IDH was a characteristic found in all cases. Patients with classic IDH lesions who are serologically negative should be investigated by PCR. Therefore, the indispensable criteria for diagnosis are (1) presence of erythematous-scaly, exudative, and crusted lesions involving ≥3 areas, including the scalp and retroauricular regions; (2) recurring nature of the lesions; and (3) a finding of HTLV-1 infection by serology or molecular biology.

Vida reprodutiva de pessoas vivendo com HIV/AIDS: revisando a literatura

No contexto atual da epidemia de HIV/AIDS, temáticas como a reprodução e a transmissão materno-infantil tornaram-se frequentes e têm suscitado diversos posicionamentos por parte de pessoas portadoras e das equipes de saúde. O presente artigo teve por objetivo examinar o impacto da infecção por HIV/AIDS na vida reprodutiva de pessoas portadoras, considerando o direito à maternidade e à paternidade. Foi realizada uma revisão da literatura acerca de aspectos biológicos, psíquicos e sociais que compõem o cenário da assistência em saúde reprodutiva. Constatou-se que a prevalência da lógica biomédica e o impacto social da epidemia restringem o exercício do direito à maternidade e à paternidade dos indivíduos portadores de HIV/AIDS. Diante disso, entende se que as políticas públicas e as ações em saúde devem ser direcionadas pelo respeito ao princípio da integralidade e pelo respeito à autonomia individual, dentro de um contexto de apoio e orientação psicossocial.

[Prevalence of human T-cell lymphotropic virus (HTLV-1/2) infection among puerperae in Cuiabá, Mato Grosso, 2006]

The prevalence of human T-cell lymphotropic virus (HTLV-1/2) infection among puerperae in the State of Mato Grosso, Brazil, is unknown. Through this cross-sectional study, the prevalence of HTLV-1/2 infection among puerperae attended at three public maternity hospitals in Cuiabá, State of Mato Grosso, was defined. Between April and September 2006, 3,831 deliveries took place and 2,965 puerperae underwent serological tests for HTLV-1/2: enzyme-linked immunosorbent assay (ELISA) and western blot. The mean age of the women studied was 23.9 years. The prevalence of HTLV-1/2 was 0.2%, i.e. similar to the prevalence observed in the general population of many developed centers in Brazil. This finding of low prevalence suggests that there is still no justification for introducing public health interventions for the population of pregnant women in our setting, to reduce the vertical transmission of HTLV-1/2.

[HTLV 1/2 infection: prenatal performance as a disease control strategy in State of 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.

Manifestações cutâneas da infecção e das doenças relacionadas ao vírus linfotrópico de células T humanas do tipo 1

O vírus linfotrópico de células T humanas tipo 1 (HTLV-1) é um retrovírus encontrado em todo o mundo e, no Brasil, tem distribuição heterogênea com várias regiões consideradas de alta prevalência. Está relacionado com doenças graves e/ou incapacitantes, como a leucemia/linfoma de células T do adulto, com a doença neurológica conhecida como mielopatia associada ao HTLV-1/paraparesia espástica tropical, com a uveíte associada ao HTLV-1 e com a dermatite infecciosa. O risco para o aparecimento dessas doenças depende, principalmente, de fatores genéticos, da forma como a infecção foi adquirida e da carga proviral. Estima-se que até 10% dos infectados possam desenvolver alguma doença relacionada ao vírus ao longo da vida. O comprometimento da pele tem sido descrito tanto nas doenças relacionadas ao HTLV-1 quanto nos indivíduos portadores assintomáticos. Vários mecanismos são propostos para explicar as lesões da pele, seja pela presença direta do vírus em células, pela imunossupressão ou por resposta inflamatória que a infecção pelo vírus poderia desencadear. Dentre as manifestações dermatológicas mais freqüentes destacam-se a xerose, as dermatofitoses e as infecções bacterianas recorrentes. Neste artigo são revistos os principais aspectos referentes à infecção e às doenças relacionadas ao HTLV- 1, com ênfase na discussão das manifestações dermatológicas observadas nesse contexto.

Leucemia/linfoma de células T do adulto

A leucemia/linfoma de células T do adulto (ATL) é tipo agressivo de doença linfoproliferativa causada pelo vírus linfotrópico para células T humanas (HTLV-I), geralmente fatal e que não responde a quimioterapia. Classifica-se em formas aguda, crônica, linfomatosa e indolente (smoldering). Outra forma clínica, a tumoral primária de pele, com características diferentes, foi sugerida recentemente. As formas aguda, linfomatosa e tumoral primária de pele são as de pior prognóstico. Os critérios diagnósticos de ATL são: sorologia positiva para o HTLV-I; diagnóstico citológico ou histológico de leucemia/linfoma de células T, CD4+/CD25+; presença de linfócitos T anormais em sangue periférico; confirmação de integração monoclonal do DNA proviral do HTLV-I. Há lesões de pele em cerca de 70% dos casos,que podem ser primários (formas indolente e tumoral primária da pele) ou secundários. As lesões cutâneas são múltiplas, sendo as mais freqüentes a eritrodermia, as pápulas e as placas. A ATL não tem aspecto histológico característico, podendo apresentar padrões superponíveis ao linfoma periférico T não especificado, à micose fungóide ou ao linfoma anaplásico de grandes células. O padrão imuno-histoquímico pode também simular o de outros tipos de linfoma T. Por esse motivo, é muito importante que no Brasil seja solicitada sorologia para o HTLV-I em todos os casos de leucemia e/ou linfoma de células T maduras.

Chipping at large, potent human T-cell leukemia virus type 1 protease inhibitors to uncover smaller, equipotent inhibitors

The human T-cell leukemia virus type 1 (HTLV-I) causes adult T-cell leukemia and several severe chronic diseases. HTLV-I protease (PR) inhibition stops the propagation of the virus. Herein, truncation studies were performed on potent octapeptidic HTLV-I PR inhibitor KNI-10161 to derive small hexapeptide KNI-10127 with some loss in activity. After performing residue-substitution studies on compound KNI-10127, HTLV-I PR inhibitory activity was recovered in inhibitor KNI-10166.

Infective dermatitis associated with the human T cell lymphotropic virus type I in Salvador, Bahia, Brazil

BACKGROUND

Infective dermatitis associated with human T cell lymphotropic virus type I (HTLV-I) infection is a chronic, relapsing eczema of childhood.

METHODS

Children, their mothers, and their siblings underwent serological testing for HTLV-I. Epidemiological data were collected from all seropositive children and their family members, and clinical and dermatological examinations were performed. Laboratory studies, including skin culture, and histopathological analyses were also performed. The diagnosis of infective dermatitis associated with HTLV-I (IDH) was made according to previously established criteria.

RESULTS

All of the patients with cases that demonstrated clinical aspects of IDH were positive for HTLV-I. The median age of the children at the time of the first visit was 8.0 years (range, 2-14 years). The median duration of breastfeeding for 19 children was 22.5 months (range, 1-48 months). The lesions were erythematous, scaly, exudative, and crusted in all cases. The scalp, retroauricular areas, neck, and groin were the regions that were commonly affected. Cultures were positive for Staphylococcus aureus for 95% of the patients. The children were followed-up for a median of 3.0 years (range, 0.1-7 years), and 5 children developed HTLV-I-associated myelopathy/tropical spastic paraparesis. All of the children except 1 were treated with sulfamethoxazole-trimethoprim, and their lesions either improved greatly or completely disappeared.

CONCLUSIONS

The present study demonstrates the severity of IDH in Bahia and confirms that its diagnosis is based almost exclusively on clinical aspects of the disease. Serological testing for HTLV-I and careful follow-up is recommended for all children with chronic, relapsing, severe eczema in regions where HTLV-I is endemic.