Seroprevalence of human T-lymphotropic virus infection among blood donors in China: a first nationwide survey

Abstract

Background So far, the prevalence of human T-lymphotropic virus (HTLV) type 1 and 2 in some highly populated countries such as China is still unknown. In this study, a multi-center nationwide serological survey was designed and performed, to reveal the seroprevalence of HTLV infection among Chinese blood donors. Results Among 8,411,469 blood donors from 155 blood establishments, 435 were finally confirmed as HTLV carriers. The prevalence of HTLV infection in China varied in different provinces: Fujian had the highest prevalence of 36.240/100,000 (95% CI 31.990–41.050) and eleven provinces did not find HTLV-seropositive donors in the three years. no HTLV-2 infection was found. The overall prevalence of HTLV-1 in China decreased from 2016 to 2018. Female was identified as an independent risk factor of HTLV infection in China. Besides, seroconversion was observed in two of seven seroindeterminate donors 85 and 250 days after their last donation, respectively. Conclusions The seroprevalence of HTLV infection in most areas of China among blood donors is quite low, but it varies significantly in different geographic areas. Screening anti-HTLV-1/2 antibody and follow-up of serointederminate donors are essential to ensure blood safety especially in areas where we have found HTLV infected donors.

Strengths, Weaknesses, Opportunities and Threats (SWOT) Analysis of the Implementation of Public Health Policies on HTLV-1 in Brazil

“…However, these data have not been routinely used to inform policymakers about HTLV-1/2 prevalence and distribution. Although the burden of infection in this specific population may underestimate the real burden of HTLV-1/2 infection, it can be a starting point for those areas of the country where there are no data available about HTLV-1/2 distribution as has been done recently in China ( 39 ).…”

Decline in human T‐cell lymphotropic virus seroprevalence in blood donors from Minas Gerais, Brazil over a 12‐year period (2006–2017)

“…Although the improvement in the specificity of the tests contributed to reducing the proportion of false‐positive results over the years, the continuous decline in the frequency of HTLV‐positive donations, including in the first‐time donors, cannot be explained by these changes, even because the confirmatory test was kept the same during the study period. A decrease in HTLV prevalence over the years has also been seen in other blood donor populations, such as Iran, 28 China, 29 and Martinique 30 . This tendency may be the result of campaigns for other sexually or blood transmitted diseases, especially HIV, which encouraged the use of condoms and needles and disposable syringes in the population.…”

Lower prevalence of anti‐HTLV‐1 as expected by previous models among first‐time blood donors in Japan

“…Blood donation sessions, therefore, provide almost no opportunity for potential HTLV‐1 carriers to self‐select and avoid blood donation in relation to subjective symptoms. Surveys of HTLV‐1 seroprevalence targeting a large number of blood donors have thus been conducted around the world 15–18 . However, it has been well recognized that blood donors in almost all countries of the world are not always representative of the general population of that country, particularly with respect to bloodborne viruses (“healthy donor effect”) 19,20 .…”

“…Surveys of HTLV-1 seroprevalence targeting a large number of blood donors have thus been conducted around the world. [15][16][17][18] However, it has been well recognized that blood donors in almost all countries of the world are not always representative of the general population of that country, particularly with respect to bloodborne viruses ("healthy donor effect"). 19,20 A survey of a hospital-based population in Nagasaki prefecture in Japan, which is endemic for HTLV-1, yielded a 50% higher prevalence than that reported from blood donor screening.…”