The East Jakarta Project: surveillance for highly pathogenic avian influenza A(H5N1) and seasonal influenza viruses in patients seeking care for respiratory disease, Jakarta, Indonesia, October 2011–September 2012

Abstract

Indonesia has reported the most human infections with highly pathogenic avian influenza (HPAI) A(H5N1) virus worldwide. We implemented enhanced surveillance in four outpatient clinics and six hospitals for HPAI H5N1 and seasonal influenza viruses in East Jakarta district to assess the public health impact of influenza in Indonesia. Epidemiological and clinical data were collected from outpatients with influenza-like illness (ILI) and hospitalized patients with severe acute respiratory infection (SARI); respiratory specimens were obtained for influenza testing by real-time reverse transcription-polymerase chain reaction. During October 2011-September 2012, 1131/3278 specimens from ILI cases (34·5%) and 276/1787 specimens from SARI cases (15·4%) tested positive for seasonal influenza viruses. The prevalence of influenza virus infections was highest during December-May and the proportion testing positive was 76% for ILI and 36% for SARI during their respective weeks of peak activity. No HPAI H5N1 virus infections were identified, including hundreds of ILI and SARI patients with recent poultry exposures, whereas seasonal influenza was an important contributor to acute respiratory disease in East Jakarta. Overall, 668 (47%) of influenza viruses were influenza B, 384 (27%) were A(H1N1)pdm09, and 359 (25%) were H3. While additional data over multiple years are needed, our findings suggest that seasonal influenza prevention efforts, including influenza vaccination, should target the months preceding the rainy season.

Physician's knowledge, attitudes, and practices regarding seasonal influenza, pandemic influenza, and highly pathogenic avian influenza A (H5N1) virus infections of humans in Indonesia

“…Very few physicians reported ever diagnosing a patient with pandemic influenza or with suspected HPAI H5N1 in either outpatients or hospitalized patients. A recent one‐year surveillance study reported that 15.5% of hospitalized patients with severe acute respiratory infection (SARI) tested positive for influenza viruses, including 36% during weeks of peak influenza activity in East Jakarta District, Jakarta, Indonesia . Together with our findings, this suggests that Indonesian clinicians need to be educated further about the potential for influenza to cause severe illness resulting in hospitalization.…”

“…Together with our findings, this suggests that Indonesian clinicians need to be educated further about the potential for influenza to cause severe illness resulting in hospitalization. Additionally, physicians should be educated on the value of surveillance data to better understand when seasonal influenza viruses are circulating and on the burden of seasonal influenza in Indonesia, such as the results of ongoing enhanced influenza surveillance among SARI patients …”

“…In addition to sporadic human infections with HPAI H5N1 virus in Indonesia, seasonal influenza A and B viruses circulate among people. Limited surveillance data suggest that seasonal influenza viruses circulate year‐round in Indonesia, with increased activity during November to March, the rainy season months . However, data on seasonal influenza disease burden in Indonesia are limited.…”

Literature review of the epidemiology of influenza B disease in 15 countries in the Asia‐Pacific region

“…Three of these papers were based on ILI surveillance of multiple seasons, reporting a proportion of type B viruses between 25.4% and 36% among all influenza‐positive samples during the overall study period . Two papers provided season‐specific information on the proportion of influenza B among all ILI cases with laboratory‐confirmed influenza in 2010‐11 and 2011‐12 . One of them also provided data in SARI patients with laboratory‐confirmed influenza in 2011‐12.…”

“…In that study, the influenza detection rate was higher among ILI than among SARI patients (34.5% vs 15.4%). In both patient groups, 47% of laboratory‐confirmed influenza cases were influenza B …”