Background
Estimates of influenza‐associated outpatient consultations and hospitalizations are severely limited in low‐ and middle‐income countries, especially in Africa.
Methods
We conducted active prospective surveillance for influenza‐like illness (ILI) and severe acute respiratory illness (SARI) at 5 healthcare facilities situated in Kinshasa Province during 2013‐2015. We tested upper respiratory tract samples for influenza viruses using a reverse transcription‐polymerase chain reaction assay. We estimated age‐specific numbers and rates of influenza‐associated ILI outpatient consultations and SARI hospitalizations for Kinshasa Province using a combination of administrative and influenza surveillance data. These estimates were extrapolated to each of the remaining 10 provinces accounting for provincial differences in prevalence of risk factors for pneumonia and healthcare‐seeking behavior. Rates were reported per 100 000 population.
Results
During 2013‐2015, the mean annual national number of influenza‐associated ILI outpatient consultations was 1 003 212 (95% Confidence Incidence [CI]: 719 335‐1 338 050 ‐ Rate: 1205.3; 95% CI: 864.2‐1607.5); 199 839 (95% CI: 153 563‐254 759 ‐ Rate: 1464.0; 95% CI: 1125.0‐1866.3) among children aged <5 years and 803 374 (95% CI: 567 772‐1 083 291 ‐ Rate: 1154.5; 95% CI: 813.1‐1556.8) among individuals aged ≥5 years. The mean annual national number of influenza‐associated SARI hospitalizations was 40 361 (95% CI: 24 014‐60 514 ‐ Rate: 48.5; 95% CI: 28.9‐72.7); 25 452 (95% CI: 19 146‐32 944 ‐ Rate: 186.5; 95% CI: 140.3‐241.3) among children aged <5 years and 14 909 (95% CI: 4868‐27 570 ‐ Rate: 21.4; 95% CI: 28.9‐72.7) among individuals aged ≥5 years.
Conclusions
The burden of influenza‐associated ILI outpatient consultations and SARI hospitalizations was substantial and was highest among hospitalized children aged <5 years.