One-year epidemiological patterns of respiratory pathogens across age, gender, and seasons in Chengdu during the post-COVID era

Abstract

Respiratory tract infections caused by various pathogens remain a significant public health concern due to their high prevalence and potential for severe complications. This study systematically analyzed the epidemiological characteristics of six common respiratory pathogens-Chlamydia pneumoniae (CP), Mycoplasma pneumoniae (MP), Adenovirus (AdV), Influenza A virus (FluA), Influenza B virus (FluB), and Respiratory Syncytial Virus (RSV)-in patients from Sichuan Jinxin Xinan Women and Children's Hospital between April 2023 and March 2024. Throat swab samples were collected from a total of 22,717 individuals. Each sample was processed using the AUTOMOLEC 3000 analyzer and the PCR-fluorescent probe method. The results showed that 10,171 (44.8%) individuals tested positive for at least one pathogen. MP had the highest overall positive rate (21.83%), followed by FluA (17.50%) and FluB (14.84%). MP showed the highest mean monthly (average) positive rate (16.84% ± 8.41). Significant differences were found between MP and AdV, CP and RSV in average positive rate (p < 0.05). Co-infection analysis revealed frequent associations between MP and AdV, MP and CP, and FluB with MP. Seasonal analysis indicated distinct peaks: FluA and FluB in winter, RSV in spring, and MP in summer, autumn and winter. Age-stratified analysis showed higher positivity rates of RSV in children aged 0-6 years, MP and CP in the 7-17 years group. Gender-based differences were only observed in RSV positive samples. These findings provide crucial insights into the prevalence and seasonal distribution of respiratory pathogens in Chengdu, offering valuable data to inform public health strategies in the post-COVID era.

Keywords: Age and gender distribution; Epidemiology; Post-COVID era; Respiratory pathogens; Seasonal Variation.

Fig. 1

Overview of respiratory pathogen. (A) Bar graph showing the overall positive rates of CP, MP, AdV, FluA, FluB, and RSV. (B) Violin plot showing the anverage monthly positive rates of CP, MP, AdV, FluA, FluB, and RSV. (C) Network diagram illustrating the co-infection relationships among CP, MP, AdV, FluA, FluB, and RSV. The size of the circles, the thickness of the lines, and the intensity of the line colors represent the frequency of co-infections. (D) Bar Chart of Co-infection Positivity Rates for CP, MP, AdV, FluA, FluB, and RSV. (E) Monthly distribution of the number of tested samples and corresponding positive rates for CP, MP, AdV, FluA, FluB, and RSV. CP (Chlamydia pneumoniae), MP (Mycoplasma pneumoniae), AdV (Adenovirus), FluA (Influenza A virus), FluB (Influenza B virus), and RSV (Respiratory syncytial virus). ** indicates p < 0.01, **** indicates p < 0.0001.

Fig. 2

Gender-specific analysis of respiratory pathogen positivity rates. (A) Heatmap showing the positive rates of CP, MP, AdV, FluA, FluB, and RSV across different genders. (B) Violin plot showing the average monthly positive rates of CP, MP, AdV, FluA, FluB, and RSV across different genders. (C) Violin plot showing the average of gender proportion in positive samples of CP, MP, AdV, FluA, FluB, and RSV. (D) Monthly distribution of gender proportion in RSV positive samples. CP (Chlamydia pneumoniae), MP (Mycoplasma pneumoniae), AdV (Adenovirus), FluA (Influenza A virus), FluB (Influenza B virus), and RSV (Respiratory syncytial virus). ** indicates p < 0.01.

Fig. 3

Seasonal analysis of respiratory pathogen positivity rates. (A) Heatmap showing the positive rates of CP, MP, AdV, FluA, FluB, and RSV across different seasons. (B) Average monthly positive rates of CP, MP, AdV, FluA, FluB, and RSV across different seasons. CP (Chlamydia pneumoniae), MP (Mycoplasma pneumoniae), AdV (Adenovirus), FluA (Influenza A virus), FluB (Influenza B virus), and RSV (Respiratory syncytial virus). Spring, Summer, Autumn, and Winter correspond to March–May (month 3–5), June–August (month 6–8), September–November (month 9–11), and December–February (month 12 − 2), respectively. * Indicates p < 0.05.

Fig. 4

Analysis of respiratory pathogen positivity rates across different age groups. (A) Heatmap showing the positive rates of CP, MP, AdV, FluA, FluB, and RSV across different age groups. (B) Average monthly positive rates of CP, MP, AdV, FluA, FluB, and RSV across different age groups. (C) Monthly distribution of positive rates for CP, MP, AdV, FluA, FluB, and RSV across different age groups. CP (Chlamydia pneumoniae), MP (Mycoplasma pneumoniae), AdV (Adenovirus), FluA (Influenza A virus), FluB (Influenza B virus), and RSV (Respiratory syncytial virus). * Indicates p < 0.05, ** indicates p < 0.01, *** indicates p < 0.001.