Mortality burden from seasonal influenza in Chongqing, China, 2012–2018

Abstract

Purpose: To estimate influenza-associated excess mortality rates (EMRs) in Chongqing from 2012 to 2018. Methods: We obtained weekly mortality data for all-cause and four underlying causes of death (circulatory and respiratory disease (CRD), pneumonia and influenza (P&I), chronic obstructive pulmonary disease (COPD) and ischemic heart disease (IDH)), and influenza surveillance data, from 2012 to 2018. A negative-binomial regression model was used to estimate influenza-associated EMRs in two age groups (<65 years and ≥65 years). Results: It was estimated that an annual average of 10025 influenza-associated deaths occurred in Chongqing, corresponding to 5.2% of all deaths. The average EMR for all-cause death associated with influenza was 33.5 (95% confidence interval (CI): 31.5-35.6) per 100 000 persons, and in separate causespecific models we attributed 24.7 (95% CI: 23.3-26.0), 0.8 (95% CI: 0.7-0.8), 8.5 (95% CI: 8.1-9.0) and 5.0 (95% CI: 4.7-5.3) per 100 000 persons EMRs to CRD, P&I, COPD and IDH, respectively. The estimated EMR for influenza B virus was 20.6 (95% CI: 20.3-21.0), which was significantly higher than the rates of 5.3 (95% CI: 4.5-6.1) and 7.5 (95% CI: 6.7-8.3) for A(H3N2) and A(H1N1) pdm09 virus, respectively. The estimated EMR was 152.3 (95% CI: 136.1-168.4) for people aged ≥65 years, which was significantly higher than the rate for those aged <65 years (6.8, 95% CI: 6.3-7.2). Conclusions: Influenza was associated with substantial EMRs in Chongqing, especially among elderly people. Influenza B virus caused a relatively higher excess mortality impact compared with A(H1N1) pdm09 and A(H3N2). It is advisable to optimize future seasonal influenza vaccine reimbursement policy in Chongqing to curb disease burden. ARTICLE HISTORY

Effect of meteorological factors on the activity of influenza in Chongqing, China, 2012–2019

“…With the latitude of 29.6°N and a subtropical climate with four distinct seasons, Chongqing is the largest municipality with over 30 million registered inhabitants in China. Our previous studies demonstrated a substantial in uenza mortality burden in Chongqing 4 , and absolute humidity has a signi cant impact on in uenza and pneumonia mortality among elderly people 5 . However, it remains unclear whether other meteorological factors such as temperature, relative humidity, precipitation, wind speed and sunshine affect the activity of in uenza.…”

Immune Mechanisms in Cardiovascular Diseases Associated With Viral Infection

“…Guan et al found a positive association between IgG and influenza A/B in patients with MI when compared to patients without MI (18,25). A recent study has shown that influenza-associated cardiovascular excess mortality, including ischemic heart disease, is higher with influenza B virus infection than pandemic influenza A strains (H1N1 and H3N2) (26).…”

“…Zhou et al have shown that the presence of at least 1 µg/ml of D-Dimer is associated with 18 times higher mortality rate in COVID-19 patients (14). Out of 172 COVID-19 patients analyzed, 68% patients showed >0.5 µg/ml of D-Dimer levels suggestive of increased mortality rate among these patients (26). However, in 2009 H1N1 influenza-infected patients, a study has shown concentrations of 1.13 ± 1.09 µg/ml of D-Dimer in patients from non-respiratory failure group versus 6.74 ± 5.11 µg/ml in patients in the respiratory failure group (141).…”

Effect of meteorological factors on the activity of influenza in Chongqing, China, 2012–2019

“…With the latitude of 29.6°N and a subtropical climate with four distinct seasons, Chongqing is the largest municipality with over 30 million registered inhabitants in China. Our previous studies demonstrated a substantial influenza mortality burden in Chongqing [ 4 ], and absolute humidity has a significant impact on influenza and pneumonia mortality among elderly people [ 5 ]. However, it remains unclear whether other meteorological factors such as temperature, relative humidity, precipitation, wind speed and sunshine affect the activity of influenza.…”