Detecting influenza and emerging avian influenza virus by influenza and pneumonia surveillance systems in a large city in China, 2005 to 2016

Abstract

Background: Detecting avian influenza virus has become an important public health strategy for controlling the emerging infectious disease. This study aimed to analyze the efficiency of two surveillance systems in detecting the emerging avian influenza viruses. Methods: A modified influenza surveillance system (ISS) and a new built pneumonia surveillance system (PSS) have been used to monitor the viruses in Changsha City, China. The ISS is based on monitoring outpatients in two sentinel hospitals to detect mild influenza and avian influenza cases, and PSS is based on monitoring inpatients in all 49 hospitals to detect severe and death influenza cases. Results: During the study period, 3551917 outpatients were monitored by the ISS system, among which 126076 were influenza-like illness (ILI) cases, with the ILI% of 3.55%. Totally, 14913 throat swabs were collected by the ISS system, among which 2016 were tested positive of influenza or avian influenza virus. Among the positive results, 621 were H3N2, 135 were seasonal H1N1, 610 were influenza A/H1N1 (pandemic in 2009), 106 were untyped influenza A, 540 were B, 1 was H5N6, 1 was H7N9, and 2 were H9N2 virus. 5491560 inpatient people were monitored by the PSS system, among which 6.61% (362743/5491560) were pneumonia cases. 10.55% (38260/362743) of reported pneumonia was severe or death cases. 3401 throat swab or lower respiratory tract samples were collected, among which 2094 were tested positive of influenza or avian influenza virus. Among the positive results, 78 were H3N2, 17 were seasonal H1N1, 1871 were influenza A/H1N1, 103 were untyped influenza A, 16 were B, 1 was H5N6, and 8 were H7N9 virus. Of 15 avian influenza cases reported from January, 2005 to September, 2016, 26.7% (4/15) were mild cases detected by the ISS system, while 60.0% (9/15) were severe or death cases detected by the PSS system. Two H5N1 severe cases were missed by the ISS system in January, 2009 when the PSS system was not available. Conclusion: The two systems seem to be of high efficiency in detecting the emerging avian influenza viruses but need to be verified in other cities or countries.

Efficacy of phentolamine combined with ambroxol aerosol inhalation in the treatment of pediatric severe pneumonia and its effect on serum IL-10 and CRP levels

“…A study (12) has confirmed that pneumonia is a lung inflammatory response caused by environmental or viral factors. Early clinical symptoms of pediatric pneumonia, such as mild cough, are not obvious, and are often ignored by parents, and can result in severe pneumonia (13)(14)(15).…”