The Seroprevalence of Some Pathogen Specific IgM in Children with Acute Respiratory Tract Infections in Guangzhou Region, 2011 - 2012.

Background: Acute respiratory tract infections (ARTIs) are the leading cause of morbidity and death in children < 5 years worldwide. The aim of this study is to analyze the seroprevalence of nine pathogen specific IgMs in children with ARTIs with respect to gender, age, and seasonality in the Guangzhou region.

Methods: Serum samples were collected from 20160 children with ARTIs admitted to the Guangzhou Women and Children's Medical Center between 2011 and 2012. Serum-specific IgM antibodies to nine respiratory pathogens, Mycoplasma pneumonia (MP), Legionella pneumophila (LP), Coxiella burnetii (C. burnetii), Chlamydophila pneumonia (CP), adenovirus (ADV), respiratory syncytial virus (RSV), type A and type B influenza virus (IVA and IVB), and parainfluenza virus (PIV), were detected using immunofluorescence assay.

Results: The male-to-female ratio of all patients was 1.9:1. The median age was 3 years and 8 months with a significant difference in seropositivity to respiratory tract pathogens between children from different age groups. Seropositivity was detected in 43.53% of the children with the top three pathogens being MP (33.15%), RSV (10.27%), and ADV (6.63%), followed by IVB (2.63%), LP (2.25%), IVA (1.59%), PIV (1.57%), CP (0.27%), and C. burnetii (0.13%). The prevalence of single, double, and triple seropositivity was 70.20% (6160/8775), 25.22% (2213/8775), and 4.57% (401/8775), respectively. The total IgM seropositivity for any kind of pathogen in the nine kinds of pathogens peaked in winter (46.53%), while the nadir was observed in summer (41.97%).

Conclusions: The top three seroprevalence of nine kinds of pathogen specific IgM was MP, followed by RSV and ADV. The epidemic pathogen specific IgM had a season-specific seropositivity distribution. Seroprevalence of the pathogen should be a focus of attention.