Detection of Viruses and Mycoplasma pneumoniae in Hospitalized Patients with Severe Acute Respiratory Infection in Northern China, 2015-2016.

Severe acute respiratory infection (SARI) presents a huge disease and economic burden worldwide. The present study described the frequency and types of different infectious etiologies among hospitalized patients with SARI in Tianjin, China, during 2015 and 2016. Basic information, in addition to a throat or serum sample, was collected from SARI patients. Nine viruses were detected using reverse transcription polymerase chain reaction, and Mycoplasma pneumoniae was detected using the Serodia Myco II gelatin particle agglutination test. A total of 585 specimens from 2,290 SARI cases were collected. The most common infection (19.66%, 115/585) was M. pneumoniae, followed by influenza virus A/B (6.15%, 36/585), and respiratory syncytial virus (4.96%, 29/585). Identification of viral or M. pneumoniae infections was the highest in the pediatric medicine ward (74.84%, 119/159), followed by the intensive care unit (37.04%, 80/216) and respiratory medicine ward (34.29%, 72/210). M. pneumoniae was highest (38.71%, 24/62) in the 5-14-year age group. Influenza was the main infection in January 2015 and March 2016. The correlation coefficient for the proportion of hospitalized cases of SARI and the positive detection rate within the same week was 0.25. M. pneumoniae and influenza were the leading pathogens among hospitalized SARI patients. A continued surveillance of hospitalized cases of SARI can detect emerging diseases, such as avian influenza A (H7N9) virus and other respiratory disease outbreaks.