Urgent need to prevent mother-to-child transmission of HTLV-1 in Jamaica

There is an urgent need to prevent mother to child transmission (MTCT) of Human T-cell Lymphotropic Virus Type-1 (HTLV-1) infection in Jamaica and the Caribbean. This can readily be done by introducing routine HTLV-1 testing of pregnant women and advising those who are seropositive to abstain from or restrict breastfeeding to four months or less.1Hino S. Establishment of the milk-borne transmission as a key factor for the peculiar endemicity of human T-lymphotropic virus type 1 (HTLV-1): the ATL Prevention Program Nagasaki.Proc Jpn Acad Ser B Phys Biol Sci. 2011; 87: 152-166https://doi.org/10.2183/pjab.87.152Crossref Scopus (112) Google Scholar,2Miyazawa T. Hasebe Y. Murase M. Sakurai M. Itabashi K. Yonemoto N. The effect of early postnatal nutrition on human T cell leukemia virus type 1 mother-to-child transmission: a systematic review and meta-analysis.Viruses. 2021; 13: 819https://doi.org/10.3390/v13050819Crossref Scopus (5) Google Scholar Prevalence of HTLV-1 is higher in women than men and increases with age and multiparity, with 1.5%–10.9% of women of reproductive age in Jamaica being HTLV-1 infected.3Murphy E.L. Figueroa J.P. Gibbs W.N. et al.Human T-lymphotropic virus type I (HTLV-I) seroprevalence in Jamaica: I. Demographic determinants.Am J Epidemiol. 1991; 133: 1114-1124Crossref PubMed Google Scholar Approximately 18%–26% of breastfed infants born to HTLV-1 seropositive mothers acquire the infection.1Hino S. Establishment of the milk-borne transmission as a key factor for the peculiar endemicity of human T-lymphotropic virus type 1 (HTLV-1): the ATL Prevention Program Nagasaki.Proc Jpn Acad Ser B Phys Biol Sci. 2011; 87: 152-166https://doi.org/10.2183/pjab.87.152Crossref Scopus (112) Google Scholar A prospective cohort study in Kingston found that among children observed for at least 24 months, 19 (32%) of 60 children breastfed for 12 months or longer were HTLV-I seropositive, compared with only 8 (9%) of 86 children breastfed for less than 12 months (relative risk, 3.4; 95% CI, 1.7–6.9).4Wiktor S.Z. Pate E.J. Rosenberg P.S. et al.Mother-to-child transmission of human T-cell lymphotropic virus type I associated with prolonged breastfeeding.J Hum Virol. 1997; 1: 37-44PubMed Google Scholar HTLV-1 can cause several associated diseases in later life, including a very aggressive cancer known as Adult T-cell Lymphoma/Leukaemia (ATL)5Mehta-Shah N. Ratner L. Horwitz S.M. Adult T-cell leukmia/lymphoma.J Oncol Pract. 2017; 13: 487-492https://doi.org/10.1200/JOP.2017.021907Crossref PubMed Scopus (43) Google Scholar; HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP), an incapacitating, progressive neurological disorder6Yamano Y. Sato T. Clinical pathophysiology of human T-lymphotropic virus-type 1-associated myelopathy/tropical spastic paraparesis.Front Microbiol. 2012; 3: 389https://doi.org/10.3389/fmicb.2012.00389Crossref PubMed Scopus (141) Google Scholar; Infective Dermatitis in children,7La Grenade L. HTLV-I, infective dermatitis, and tropical spastic paraparesis.Mol Neurobiol. 1994; 8: 147-153https://doi.org/10.1007/BF02780665Crossref Scopus (6) Google Scholar and other inflammatory diseases as well as increased risk of death due to any cause.8Schierhout G. McGregor S. Gessain A. Einsiedel L. Martinello M. Kaldor J. Association between HTLV-1 infection and adverse health outcomes: a systematic review and meta-analysis of epidemiological studies.Lancet Infect Dis. 2020; 20: 133-143https://doi.org/10.1016/S1473-3099(19)30402-5Summary Full Text Full Text PDF PubMed Scopus (132) Google Scholar There is no cure or effective treatment for ATL and the other diseases associated with the virus; nor is there a vaccine. Transmission is primarily vertical, from mother to child through breastfeeding, or sexual. There is an increased risk of these illnesses if infection happens early in life and vertical transmission of HTLV-1 is associated with the highest risk of developing ATL.9Murphy E.L. Hanchard B. Figueroa J.P. et al.Modelling the risk of adult t-Cell leukemia/lymphoma in persons infected with HTLV-I.Int J Cancer. 1989; 43: 250-253Crossref PubMed Google Scholar ATL usually occurs among persons aged 40 years or older due to a long incubation period lasting decades.5Mehta-Shah N. Ratner L. Horwitz S.M. Adult T-cell leukmia/lymphoma.J Oncol Pract. 2017; 13: 487-492https://doi.org/10.1200/JOP.2017.021907Crossref PubMed Scopus (43) Google Scholar It has a dismal prognosis with an average survival time of less than one year.5Mehta-Shah N. Ratner L. Horwitz S.M. Adult T-cell leukmia/lymphoma.J Oncol Pract. 2017; 13: 487-492https://doi.org/10.1200/JOP.2017.021907Crossref PubMed Scopus (43) Google Scholar We estimate that approximately 15–20 new cases of ATL occur annually in Jamaica. The lifetime risk of developing ATL is 2.5%–5%.5Mehta-Shah N. Ratner L. Horwitz S.M. Adult T-cell leukmia/lymphoma.J Oncol Pract. 2017; 13: 487-492https://doi.org/10.1200/JOP.2017.021907Crossref PubMed Scopus (43) Google Scholar Without the introduction of routine antenatal screening and limiting breastfeeding among HTLV-1 infected mothers, ATL will continue to occur indefinitely. HAM/TSP is a chronic neurological condition occurring in approximately 0.25–3.8% of HTLV-1-infected individuals and characterised by spastic weakness of the lower legs.6Yamano Y. Sato T. Clinical pathophysiology of human T-lymphotropic virus-type 1-associated myelopathy/tropical spastic paraparesis.Front Microbiol. 2012; 3: 389https://doi.org/10.3389/fmicb.2012.00389Crossref PubMed Scopus (141) Google Scholar HAM/TSP is associated with significant morbidity and disability resulting in poor quality of life. Infective Dermatitis was first described in Jamaican children and usually occurs early in childhood presenting with recurrent severe, exudative dermatitis involving the scalp, eyelid margins, nasal fold, neck, external ear, retro-auricular areas, axillae and groin.7La Grenade L. HTLV-I, infective dermatitis, and tropical spastic paraparesis.Mol Neurobiol. 1994; 8: 147-153https://doi.org/10.1007/BF02780665Crossref Scopus (6) Google Scholar Although routine HTLV-1 screening of blood donors in Jamaica was introduced nearly four decades ago there is no screening of pregnant women. The public health consequences of failing to interrupt vertical transmission of HTLV-1 are greater than failing to screen blood donors for HTLV-1. Almost all ATL and infective dermatitis cases and up to 30% of HAM/TSP cases are associated with mother to child transmission.10Rosadas C. Taylor G.P. Mother-to-Child HTLV-1 transmission: unmet research needs.Front Microb. 2019; 10: 999https://doi.org/10.3389/fmicb.2019.00999Crossref PubMed Scopus (76) Google Scholar This raises significant ethical issues because pregnant women are denied the opportunity to know their HTLV-1 status and prevent their newborns from becoming infected. Some may argue that the cost of antenatal screening may be too high for Jamaica. An economic analysis conducted in the UK, where HTLV-1 prevalence is significantly lower than in Jamaica, showed that antenatal screening met key criteria for a screening program and was cost-effective.11Malik B. Taylor G.P. Can we reduce the incidence of adult T-cell leukaemia/lymphoma? Cost-effectiveness of human T-lymphotropic virus type 1 (HTLV-1) antenatal screening in the United Kingdom.Br J Haematol. 2019; 184: 1040-1043https://doi.org/10.1111/bjh.15234Crossref PubMed Scopus (22) Google Scholar Economic studies in Japan12Kowada A. Cost-effectiveness of human T-cell leukemia virus type 1 (HTLV-1) antenatal screening for prevention of mother-to-child transmission.PLoS Negl Trop Dis. 2023; 17e0011129https://doi.org/10.1371/journal.pntd.0011129Crossref Scopus (1) Google Scholar and Brazil13Rosadas C. Senna K. da Costa M. et al.Economic analysis of antenatal screening for human T-cell lymphotropic virus type 1 in Brazil: an open access cost-utility model.Lancet Glob Health. 2023; 11: e781-e790https://doi.org/10.1016/S2214-109X(23)00065-7Summary Full Text Full Text PDF PubMed Scopus (8) Google Scholar have shown that HTLV-1 screening of pregnant women is highly cost-effective. In Japan, implementing a national antenatal screening program has reduced mother-to-child transmission of HTLV-1 from 20% to 2.5%.1Hino S. Establishment of the milk-borne transmission as a key factor for the peculiar endemicity of human T-lymphotropic virus type 1 (HTLV-1): the ATL Prevention Program Nagasaki.Proc Jpn Acad Ser B Phys Biol Sci. 2011; 87: 152-166https://doi.org/10.2183/pjab.87.152Crossref Scopus (112) Google Scholar PAHO has recognised HTLV-1 as an emerging concern and now includes it in the goal to eliminate mother-to-child transmission of HIV, Hepatitis B, congenital syphilis, congenital Chagas and HTLV-1 as public health problems in the Americas.14PAHOThe response to HTLV in the framework of maternal and child health. Meeting report, 18 August 2022 (virtual).https://iris.paho.org/handle/10665.2/56888Date accessed: February 16, 2024Google Scholar In the Caribbean, only St Lucia and possibly Martinique do routine HTLV-1 prenatal screening. However, Brazil has taken the decision to implement national prenatal screening. There is no good reason for not introducing routine HTLV-1 screening of all pregnant women in Jamaica and other countries where HTLV-1 prevalence is relatively high. JPF–Conceptualisation, wrote the original draft, review & editing. CJC–Review & Editing. JJD–Review & Editing. JJ–Review & Editing. None.