Global Prevalence of Preexisting Antibodies against Human Adenoviruses, Surveyed from 1962 to 2021.

BACKGROUND: Human adenoviruses (HAdVs) are extensively used as vectors for vaccines development and cancer therapy. People who already have antibodies against HAdVs, on the other hand, would have an impact on the preventative or therapeutic effect. This review focuses primarily on the prevalence of pre-existing antibodies against HAdVs in distinct geographical populations. SUMMARY: After screening, 64 studies from 31 countries between 1962 and 2021 were selected, totaling 39,427 samples. The total prevalence of preexisting antibodies to HAdVs varied by country or location, ranging from 2.00 to 95.70%. Southeast Asia had the highest prevalence (54.57%) while Europe had the lowest (18.17%). The prevalence in practically all developing nations was higher than in developed nations. Adults have a greater frequency than children and newborns in most nations. The primary HAdV antibody types varied by country. Adults in China, the USA, the United Kingdom, and Belgium had the lowest prevalence of preexisting antibodies against HAdV55, HAdV37, HAdV8, and HAdV36, respectively. Children in the USA, China, the United Kingdom, and Japan had the lowest rates of HAdV48, HAdV11, HAdV8, and HAdV40. The frequency of antibodies differed significantly between military and civilian groups. KEY MESSAGES: Preexisting antibodies against various types of HAdVs differed greatly throughout worldwide populations. Future development of HAdV-vector vaccines and medicines should focus on preexisting antibodies in target groups rather than a "one-size-fits-all" strategy. It might be advantageous in selecting HAdV vectors for studying the prevalence of preexisting antibodies against HAdVs in different locations and people throughout the world.

Diversity of species and geographic distribution of tick-borne viruses in China.

Introduction: Tick-borne pathogens especially viruses are continuously appearing worldwide, which have caused severe public health threats. Understanding the species, distribution and epidemiological trends of tick-borne viruses (TBVs) is essential for disease surveillance and control. Methods: In this study, the data on TBVs and the distribution of ticks in China were collected from databases and literature. The geographic distribution of TBVs in China was mapped based on geographic locations of viruses where they were prevalent or they were detected in vector ticks. TBVs sequences were collected from The National Center for Biotechnology Information and used to structure the phylogenetic tree. Results: Eighteen TBVs from eight genera of five families were prevalent in China. Five genera of ticks played an important role in the transmission of TBVs in China. According to phylogenetic analysis, some new viral genotypes, such as the Dabieshan tick virus (DTV) strain detected in Liaoning Province and the JMTV strain detected in Heilongjiang Province existed in China. Discussion: TBVs were widely distributed but the specific ranges of viruses from different families still varied in China. Seven TBVs belonging to the genus Orthonairovirus of the family Nairoviridae such as Nairobi sheep disease virus (NSDV) clustered in the Xinjiang Uygur Autonomous Region (XUAR) and northeastern areas of China. All viruses of the family Phenuiviridae except Severe fever with thrombocytopenia syndrome virus (SFTSV) were novel viruses that appeared in the last few years, such as Guertu virus (GTV) and Tacheng tick virus 2 (TcTV-2). They were mainly distributed in the central plains of China. Jingmen tick virus (JMTV) was distributed in at least fourteen provinces and had been detected in more than ten species of tick such as Rhipicephalus microplus and Haemaphysalis longicornis, which had the widest distribution and the largest number of vector ticks among all TBVs. Parainfluenza virus 5 (PIV5) and Lymphatic choriomeningitis virus (LCMV) were two potential TBVs in Northeast China that could cause serious diseases in humans or animals. Ixodes persulcatus carried the highest number of TBVs, followed by Dermacentor nuttalli and H. longicornis. They could carry as many as ten TBVs. Three strains of Tick-borne encephalitis (TBEV) from Inner Mongolia Province clustered with ones from Russia, Japan and Heilongjiang Province, respectively. Several SFTSV strains from Zhejiang Province clustered with strains from Korea and Japan. Specific surveillance of dominant TBVs should be established in different areas in China.