Novel human protoparvoviruses : epidemiology and clinical impact

Research output: ThesisDoctoral ThesisCollection of Articles

Abstract

In the beginning of the 21st century, the development of next generation sequencing (NGS) methods revolutionized the discovery of novel viruses and laid the foundations of a new era in virology. With NGS, the amount and quality of sequence data increased tremendously, and the decreasing price made large-scale screening possible. As a result, hundreds of novel viruses have been identified, and especially the number of novel small DNA viruses, including parvoviruses, has grown substantially. This thesis consists of studies of three novel parvoviruses, bufavirus (BuV), tusavirus (TuV), and cutavirus (CuV). All three viruses were originally identified by NGS from the diarrheal feces of children between 2012 and 2016, and they were the first viruses in the Protoparvovirus genus putatively infecting humans. Many of the animal viruses in this genus are known pathogens: for example, canine parvovirus (CPV) can cause severe gastroenteritis with high mortality among puppies. Currently, there are three genotypes of BuV and one genotype each of CuV and TuV. BuVs have been detected mainly in fecal samples, whereas CuV DNA has been detected in skin biopsies of cutaneous T-cell lymphoma (CTCL) and melanoma patients as well. Any findings of TuV have been rare. Here, we developed diagnostic methods for detecting viral DNA and IgG antibodies against BuV1-3, TuV and CuV, and analyzed 4300 samples from 11 cohorts on four continents to determine the epidemiology and potential clinical impact of these viruses. The BuV DNA was detected in diarrheal fecal samples from both adults and children in Finland, although with low prevalence. In addition, one nasal swab harbored BuV DNA. These studies were among the first to show BuV circulation in Europe and among adults, and further, the nasal swab is still the only non-fecal human sample containing BuV DNA. Although we detected BuV exclusively in diarrheic feces, our results did not strongly support a major role of BuV in gastroenteritis. One of the main findings in this thesis was the remarkable difference observed in the BuV seroprevalence between different populations: in the Middle East and Africa, the BuV IgG antibodies were detected in 56-85% of the adult population whereas in Finland and in the USA the seroprevalence was very low,
Original languageEnglish
Supervisors/Advisors
  • Söderlund-Venermo, Maria, Supervisor
Place of PublicationHelsinki
Publisher
Print ISBNs978-951-51-6407-0
Electronic ISBNs978-951-51-6408-7
Publication statusPublished - 2020
MoE publication typeG5 Doctoral dissertation (article)

Bibliographical note

M1 - 101 s. + liitteet

Fields of Science

  • 3111 Biomedicine
  • 11832 Microbiology and virology

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