Influenza surveillance from November 2008 to 2011; including pandemic influenza A(H1N1)pdm09 in Bhutan

Influenza Other Respir Viruses. 2013 May;7(3):426-30. doi: 10.1111/j.1750-2659.2012.00409.x. Epub 2012 Jul 20.

Abstract

Objective: Describe the influenza A(H1N1) pandemic in Bhutan.

Design: Observational study from sentinel surveillance sites.

Setting: Bhutan remains isolated, with only one to two flights a day at the lone airport, no trains, and only three major roads that enter from India.

Main outcome measures: PCR positive human respiratory samples.

Results: The first case of A(H1N1)pdm09 infection was detected in Bhutan in July 2009, 3 months after the virus was first reported in Mexico in April 2009. During the official WHO pandemic period (11 June 2009 to 8 August 2010), a total of 2149 samples were collected and tested by RT-PCR of which 22.7% (487) were confirmed A(H1N1)pdm09; H3N2, H1N1, and B were positive in 2.2%, 1.1%, and 7.2%, respectively. The highest rate of A(H1N1)pdm09 cases (57.4%) was detected in the 6-20 year-old age group. Importantly, Bhutan increased from 3 sentinel sites in April 2009 to 11 a year later, and in April 2010 established PCR capability for influenza.

Conclusions: Despite relative isolation, the A(H1N1)pdm09 reached Bhutan within 3 months of identification in Mexico. The H1N1 pandemic has made Bhutan more prepared for epidemics in the future.

MeSH terms

  • Adolescent
  • Adult
  • Bhutan / epidemiology
  • Child
  • Child, Preschool
  • Female
  • Humans
  • Influenza A Virus, H1N1 Subtype / genetics
  • Influenza A Virus, H1N1 Subtype / isolation & purification*
  • Influenza A Virus, H3N2 Subtype / genetics
  • Influenza A Virus, H3N2 Subtype / isolation & purification*
  • Influenza, Human / epidemiology*
  • Influenza, Human / virology
  • Male
  • Middle Aged
  • Pandemics
  • Sentinel Surveillance*
  • Young Adult