Prevalence and Risk Factors Associated with Influenza Infections in Kampong Cham and Tbong Khmum Provinces, Cambodia


Influenza A
Influenza B
Seasonal influenza
Risk factors



Influenza epidemics occur yearly worldwide, including in Cambodia. Two types of seasonal influenza cause significant human morbidity and mortality: influenza A [A (H1N1) pdm09 and A (H3N2)] and influenza B (B/Yamagata and B/Victoria). The overall prevalence of influenza in Cambodia was approximately 38.0% (2012–2015). We aimed to determine the prevalence of influenza infection from 2013–2017 and to assess the potential risk factors for human infection with influenza in the four villages of Kampong Cham and Tbong Khmum Provinces.


We used Stata V16 to analyze data from 3756 participants aged ? 06 months who were enrolled from 2013 to 2017 in a cohort study of acute febrile disease among villagers in Kampong Cham and Tbong Khmum provinces, Cambodia. Descriptive analysis was used to describe the prevalence and demographic characteristics of influenza infection. Multivariate logistic analysis was performed to determine the main risk factors associated with influenza infection.


The participants’ mean age was 14.0 years (SD = 0.3), and 38.9% were aged 0-5 years. Females accounted for 51.6%. A total of 27.7% were confirmed to be influenza positive, in which most participants were infected with influenza A viruses (53.6%) or influenza B (46.2%). The incidence of influenza infection peaked in the rainy season. Factors independently associated with influenza infection were age 6–12 years (AOR = 1.5, 95% CI: 1.12–2.02), age 13–19 years (AOR = 1.94, 95% CI: 1.30–2.90), primary education level 1–6 years (AOR = 1.53, 95% CI: 1.16–2.00), cough (AOR = 2.96, 95% CI: 2.34–3.75), runny nose (AOR = 1.87, 95% CI: 1.55–2.26) and chills (AOR = 2.03, 95% CI: 1.71–2.41).


The highest influenza incidence was observed for types A and B, which particularly emerged in the rainy season between June and October. Younger age group, primary education, cough, runny nose, and chills were the key predictors of influenza infection.