Molecular investigation of Torque teno sus virus in geographically distinct porcine breeding herds of Sichuan, China

Abstract

BackgroundTorque teno sus virus (TTSuV), infecting domestic swine and wild boar, is a non-enveloped virus with a circular, single-stranded DNA genome. which has been classified into the genera Iotatorquevirus (TTSuV1) and Kappatorquevirus (TTSuV2) of the family Anelloviridae. A molecular study was conducted to detect evidence of a phylogenic relationship between these two porcine TTSuV genogroups from the sera of 244 infected pigs located in 21 subordinate prefectures and/or cities of Sichuan.ResultsBoth genogroups of TTSuV were detected in pig sera collected from all 21 regions examined. Of the 244 samples, virus from either genogroup was detected in 203 (83.2%), while 44 animals (18.0%) were co-infected with viruses of both genogroups. Moreover, TTSuV2 (186/244, 76.2%) was more prevalent than TTSuV1 (61/244, 25%). There was statistically significant difference between the prevalence of genogroups 1 infection alone (9.4%, 23/244) and 2 alone (64.8%, 158/244), and between the prevalence of genogroups 2 (76.2%, 186/244) and both genogroups co-infection (18.0%, 44/244). The untranslated region of the swine TTSuV genome was found to be an adequate molecular marker of the virus for detection and surveillance. Phylogenetic analysis indicated that both genogroups 1 and 2 could be further divided into two subtypes, subtype a and b. TTSuV1 subtype b and the two TTSuV2 subtypes are more prevalent in Sichuan Province.ConclusionsOur study presents detailed geographical evidence of TTSuV infection in China.

Molecular Detection of Torque Teno Sus Virus and Coinfection with African Swine Fever Virus in Blood Samples of Pigs from Some Slaughterhouses in Nigeria

“…This is in agreement with previous reports by Brinks et al [8] in Uganda and Mei et al [7] in China.…”

“…It is not clear whether sample number or sampling season played a role in the prevalence rate but our finding is in agreement with Brink et al [8] in Uganda who reported 51.6% positivity from 95 samples collected during ASF studies. TTSuV1 was detected in all the 4 slaughterhouses but the prevalence was low compared to reports from China and Uganda [7, 8]. …”

Global impact of Torque teno virus infection in wild and domesticated animals

“…In addition, the vast spread of the infection in swine and the absence of geographical clustering of the isolates have led some authors to speculate that the dissemination on a planetary scale may be partly due to the use of contaminated vaccines [13]. The global prevalence of infection varies between 16.8% and 100% for TTSuV1 [66][67][68], and between 31% and 90% for TTSuV2 [63,66,69]. Data related to infection with TTSuVk2b, the most recently identified species, are still limited.…”

“…Many recent studies have focused on TTVs that infect pigs (TTSuV). The AVs that infect swine, domestic pigs, and wild boars are spread all over the world, regardless of the race, age, gender, and state of health of the animals [30,[61][62][63]. A recent retrospective study has documented the circulation of the virus in Spanish farms since 1985 [64].…”

Complete Genome Sequence of Torque teno indri virus 1 , a Novel Anellovirus in Blood from a Free-Living Lemur

“…For example, human anelloviruses include torque teno virus ( Alphatorquevirus genus), torque teno minivirus ( Betatorquevirus ), and torque teno midi virus ( Gammatorquevirus ) ( 2 , 3 ). In addition, torque teno sus virus ( Iotatorquevirus ) and torque teno sus virus k2 ( Kappatorquevirus ) are found in swine ( 4 , 5 ). Other animal hosts include a wide range of species, including cats, gorillas, chimpanzees, and chickens ( 6 – 8 ).…”