Estimation of influenza and respiratory syncytial virus hospitalizations using sentinel surveillance data—La Paz, Bolivia. 2012–2017

OBJECTIVE: The objective was to estimate the number of hospitalizations associated with influenza and RSV using data from severe acute respiratory infection (SARI) sentinel surveillance from El Alto‐La Paz. Bolivia. METHODS: All persons who met the case definition for SARI at one sentinel hospital had a clinical sample collected and analyzed by rRT‐PCR for influenza and by indirect immunofluorescence for RSV. The SARI‐influenza and SARI‐RSV case counts were stratified by six age groups. The proportion of cases captured in the sentinel hospital in relation to the non‐sentinel hospitals of area was multiplied by the age‐specific census population, to build the denominators. The annual incidence and a 95% confidence interval (CI) were estimated. RESULTS: During 2012‐2017, n = 2606 SARI cases were reported (average incidence 120/100 000 inhabitants [95% CI: 116‐124]); the average incidence of influenza‐associated SARI hospitalization was 15.3/100 000 (95% CI: 14.1‐16.7), and the average incidence of RSV‐associated SARI hospitalization was 9/100 000 inhabitants (95% CI: 8.1‐10.1). The highest incidence of influenza was among those less than one year of age (average 174.7/100 000 [range: 89.1‐299.5]), followed by those one to four years of age (average 51.8/100 000 [range: 19.8‐115.4]) and then those 65 years of age and older (average 47.7/100 000 [range: 18.8‐117]). For RSV, the highest incidence was highest among those less than one year of age (231/100 000 [range: 119.9‐322.9]). CONCLUSION: Influenza and RSV represent major causes of hospitalization in La Paz, Bolivia—with the highest burden among children under one year of age. Our estimates support current prevention strategies in this age group.