Abstract: Objective To investigate prevalence and epidemiologic features of Saffold virus (SAFV) in hospitalized children with acute respiratory infection or digestive tract infection Tianjin area. Methods Nasopharyngeal aspirates from children with acute respiratory infection and fecal samples from children with digestive tract infection in Tianjin Children’ s Hospital were collected from January 2013 to December 2013. Viral nucleic acid was extracted, and SAFV infection was determined by using real-time quantitative PCR. Positive PCR products were sequenced. The sequencing results were aligned with known gene sequences of SAFV sequences in GenBank. The positive viral infection rate of nasopharyngeal aspirates and fecal samples, viral positive constituent ratio and positive detection rate in different age groups, seasonal distribution of SAFV infection were calculated. Other common respiratory tract or digestive tract viruses were also detected. Results Fourty-three (11.9 %) nasopharyngeal aspirates from children with acute respiratory infection tested positive for SAFV. There was no significant difference between male and female infected children (aged between 6 d and 12 years old). The 79 % (34/43) of the patients with SAFV infection aged under 1 year old. The infection most occurred in summer and winter. The 63 (16.4 %) fecal samples from children with digestive tract infection tested positive for SAFV. There was significant difference between male and female infected children (aged between 5 h and 11 years old). SAFV infection was found to be year round. There was no significant difference in different age groups of nasopharyngeal aspirates and fecal samples. The mixed infection rate with SAFV and other respiratory tract or digestive tract viruses were 7.0 %（3/43）and 12.7 %（8/63）, respectively. Conclusion Infection of SAFV had occurred in children with acute respiratory infection or digestive tract infection in Tianjin. SAFV has high detection rate in these children and is more common in children aged under 1 year old. The data suggest that some of acute respiratory infection or digestive tract infections in pediatric patients are related to SAFV. The Clinical doctors should pay attention to them ．

Key words: respiratory tract infections, gastrointestinal tract, epidemiologic studies, TIANJIN, Saffold virus, children