A Nationwide Antenatal Human T-Cell Leukemia Virus Type-1 Antibody Screening in Japan

Kazuo Itabashi; Tokuo Miyazawa; Akihiko Sekizawa; Akifumi Tokita; Shigeru Saito; Hiroyuki Moriuchi; Yasuhito Nerome; Kaoru Uchimaru; Toshiki Watanabe

doi:10.3389/fmicb.2020.00595

A Nationwide Antenatal Human T-Cell Leukemia Virus Type-1 Antibody Screening in Japan

Front Microbiol. 2020 Apr 9:11:595. doi: 10.3389/fmicb.2020.00595. eCollection 2020.

Authors

Kazuo Itabashi¹, Tokuo Miyazawa², Akihiko Sekizawa³, Akifumi Tokita⁴, Shigeru Saito⁵, Hiroyuki Moriuchi⁶, Yasuhito Nerome⁷, Kaoru Uchimaru⁸, Toshiki Watanabe⁹

Affiliations

¹ Showa University Hospital, Tokyo, Japan.
² Department of Pediatrics, Showa University School of Medicine, Tokyo, Japan.
³ Japan Association of Obstetricians and Gynecologists, Tokyo, Japan.
⁴ Japanese Pediatric Association, Tokyo, Japan.
⁵ The University of Toyama, Toyama, Japan.
⁶ Department of Pediatrics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
⁷ Faculty of Medicine, School of Health Sciences, Kagoshima University, Kagoshima, Japan.
⁸ Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan.
⁹ Future Center Initiative, and Research Hospital of the Institute of Medical Science, The University of Tokyo, Tokyo, Japan.

Abstract

Japan has been running a nationwide antenatal human T-cell leukemia virus type-1 (HTLV-1) antibody screening program since 2010 for the prevention of HTLV-1 mother-to-child transmission. As part of the program, pregnant women are invited to take an HTLV-1 antibody screening test, usually within the first 30 weeks of gestation, during regular pregnancy checkups. Pregnant women tested positive on the antibody screening test undergo a confirmatory test, either western blotting or line immunoassay. In indeterminate case, polymerase chain reaction (PCR) is used as a final test to diagnose infection. Pregnant women tested positive on a confirmatory or PCR test are identified as HTLV-1 carriers. As breastfeeding is a predominant route of postnatal HTLV-1 mother-to-child transmission, exclusive formula feeding is widely used as a postnatal preventive measure. Although there is insufficient evidence that short-term breastfeeding during ≤3 months does not increase the risk of mother-to-child transmission compared to exclusive formula feeding, this feeding method is considered if the mother is eager to breastfeed her child. However, it is important that mothers and family members fully understand that there is an increase in the risk of mother-to-child transmission when breastfeeding would be prolonged. As there are only a few clinical studies on the protective effect of frozen-thawed breastmilk feeding on mother-to-child transmission of HTLV-1, there is little evidence to recommend this feeding method. Further study on the protective effects of these feeding methods are needed. It is assumed that the risk of anxiety or depression may increase in the mothers who selected exclusive formula feeding or short-term breastfeeding. Thus, an adequate support and counseling for these mothers should be provided. In addition to raising public awareness of HTLV-1 infection, epidemiological data from the nationwide program needs to be collected and analyzed. In most cases, infected children are asymptomatic, and it is necessary to clarify how these children should be followed medically.

Keywords: confirmatory test; human T-cell leukemia virus type-1; infection; mother-to-child transmission; nationwide antenatal screening; prevention.

Publication types

Review