• Open Access

An early report from newly established laboratory-based influenza surveillance in Lao PDR


Juliet E. Bryant PhD, Hospital for Tropical Diseases, Oxford University Clinical Research Unit, 190 Ben Ham Tu, District 5, Ho Chi Minh City, Viet Nam. E-mail: jbryant@oucru.org


Please cite this paper as: Vongphrachanh P, Simmerman JM, Phonekeo D, Pansayavong V, Sisouk T, Ongkhamme S, Bryce GT, Corwin A, Bryant JE. An early report from newly established laboratory-based influenza surveillance in Lao PDR. Influenza and Other Respiratory Viruses 4(2), 47–52.

Background  Prior to 2007, little information was available about the burden of influenza in Laos. We report data from the first laboratory-based influenza surveillance system established in the Lao People’s Democratic Republic.

Methods  Three hospitals in the capital city of Vientiane began surveillance for influenza-like illness (ILI) in outpatients in 2007 and expanded to include hospitalized pneumonia patients in 2008. Nasal/throat swab specimens were collected and tested for influenza and other respiratory viruses by multiplex ID-TagTM respiratory viral panel (RVP) assay on a Luminex® 100× MAP IS instrument (Qiagen, Singapore).

Results  During January 2007 to December 2008, 287 of 526 (54·6%) outpatients with ILI were positive for at least one respiratory virus. Influenza was most commonly identified, with 63 (12·0%) influenza A and 92 (17·5%) influenza B positive patients identified. In 2008, six of 79 (7·6%) hospitalized pneumonia patients were positive for influenza A and four (5·1%) were positive for influenza B. Children <5 years represented 19% of viral infections in outpatients and 38% of pneumonia inpatients.

Conclusion  Our results provide the first documentation of influenza burden among patients with febrile respiratory illness and pneumonia requiring hospitalization in Laos. Implementing laboratory-based influenza surveillance requires substantial investments in infrastructure and training. However, continuing outbreaks of avian influenza A/H5N1 in poultry and emergence of the 2009 influenza A(H1N1) pandemic strain further underscore the importance of establishing and maintaining influenza surveillance in developing countries.