Influenza-associated Hospitalizations and Deaths, Costa Rica, 2009–2012

Abstract

Data needed to guide influenza vaccine policies are lacking in tropical countries. We multiplied the number of severe acute respiratory infections by the proportion testing positive for influenza. There were ≈6,699 influenza hospitalizations and 803 deaths in Costa Rica during 2009-2012, supporting continuation of a national influenza vaccine program.

Estimating the burden of influenza‐associated hospitalizations and deaths in Central America

“…In Guatemala, we recruited a survey team to collect the information at all public hospitals. For each month during 2009–2012, we determined the number of patients hospitalized with pneumonia or influenza diagnoses corresponding to ICD‐10 codes J09–J18, the WHO proxies for severe acute respiratory infections (SARI),6 by age‐group, that is, <5 years, 5–64 years, and >64 years, the age‐groups typically targeted for vaccination 8…”

“…Influenza surveillance among SARI case‐patients was conducted in the study countries by sentinel hospitals and National Influenza Centers according to PAHO‐CDC 2006 generic protocol for influenza surveillance 3, 6. Laboratories tested respiratory samples using immunofluorescence and rtRT‐PCR3, 6 after systematically identifying a sample of SARI cases through routine clinical practice.…”

“…Laboratories tested respiratory samples using immunofluorescence and rtRT‐PCR3, 6 after systematically identifying a sample of SARI cases through routine clinical practice. We determined the age‐stratified percentage of samples from SARI case‐patients testing positive for influenza virus by dividing the number of positive by the total sampled each same month.…”

“…Few studies have estimated the burden of influenza illness in Central America, a tropical region comprised of lower to upper‐middle‐income countries 3, 4, 5, 6. Estimating the influenza disease burden is difficult because ill persons may not seek care or present for care with ill‐defined symptoms where they are often treated empirically without respiratory sampling.…”

“…Estimating the influenza disease burden is difficult because ill persons may not seek care or present for care with ill‐defined symptoms where they are often treated empirically without respiratory sampling. Information on disease burden can be useful for local public health practitioners exploring the potential value of prevention programs 6, 7…”