Genetic typing and intrafamilial transmission of human T-lymphotropic virus type 1 in non-endemic areas of China

Huimin Ji; Le Chang; Ying Yan; Huizhen Sun; Yi Liu; Lunan Wang

doi:10.3389/fmicb.2023.1288990

Genetic typing and intrafamilial transmission of human T-lymphotropic virus type 1 in non-endemic areas of China

Front Microbiol. 2023 Oct 18:14:1288990. doi: 10.3389/fmicb.2023.1288990. eCollection 2023.

Authors

Huimin Ji^{1

2}, Le Chang^{1

2}, Ying Yan^{1

2}, Huizhen Sun^{1

2}, Yi Liu³, Lunan Wang^{1

2

4}

Affiliations

¹ National Center for Clinical Laboratories, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Sciences, Beijing, China.
² Beijing Engineering Research Center of Laboratory Medicine, Beijing Hospital, Beijing, China.
³ 63750 Military Hospital of the People's Liberation Army, Xi'an, Shaanxi, China.
⁴ Graduate School, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.

Abstract

The origin and intrafamilial transmission of Human T-Lymphotropic Virus Type 1 (HTLV-1) in non-endemic populations such as China is still unknown. In this study, donors from blood banks/centers in China (including 28 provinces and Shenzhen city) during 2019 and 2021 were screened for HTLV-1/2 antibody, and all the reactive samples were tested using a line immunoassay (LIA) and quantitative polymerase chain reaction (qPCR). Samples that can be detected using qPCR were amplified and sequenced for the long terminal repeat (LTR) region. The positive donors were contacted to identify their relatives. As a result, 4,451,883 blood donors were totally tested, and 50 of them were confirmed to be HTLV-1/2 positive. Viral LTR sequences genotyped from 26 HTLV-1 carriers demonstrated that all had the HTLV-1a genotype, of which Transcontinental and Japanese subgroups accounted for half each. There were 17 family members of 11 index donors detected, and the HTLV-1 infection rate in the spouses of male index donors (83.3%, 5/6) was significantly higher than that in the husbands of female index donors (0.0%, 0/4). However, 7 children of HTLV-1 positive women were tested and found negative. Therefore, our findings indicated that HTLV-1 is spreading silently from high-endemic to low-endemic areas in China. To prevent further HTLV-1/2 transmission, an efficient HTLV-1/2 screening strategy and counseling of the virus carriers are essential.

Keywords: T-cell lymphotropic virus type 1/2 (HTLV-1/2) HTLV-1/2; blood donors; intrafamilial transmission; phylogenetic analysis; sexual transmission.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by the Beijing Hospital Clinical Research Project (BJ-2022-182).