Timing of influenza epidemics and vaccines in the American tropics, 2002–2008, 2011–2014

Timing of influenza epidemics and vaccines in the American tropics, 2002–2008, 2011–2014

Durand O, Chen P, Palekar R, Clara W, Jara J, Cerpa M, El Omeiri N, Ropero-Alvarez AM, Barbosa J, Lara J, Acosta B, Bruno A, Calderon de Lozano C, Castillo LC, Matute ML, Jackson-Betty S, Suan Mung K, Díaz-Quinonez J, López-Martinez I, Balmaseda A, MorneoArévalo B, Vazquez C, Gutierrez V, Garten R, Widdowson MA and Azziz-Baumgartner E. Timing of influenza epidemics and vaccines in the American tropics, 2002-2008, 2011-2014. Influenza and Other Respiratory Viruses, 10(3), 170-175, 2016

doi: 10.1111/irv.12371

https://onlinelibrary.wiley.com/doi/epdf/10.1111/irv.12371

 

Description

Abstract

Background

Influenza-associated illness results in increased morbidity and mortality in the Americas. These effects can be mitigated with an appropriately chosen and timed influenza vaccination campaign. To provide guidance in choosing the most suitable vaccine formulation and timing of administration, it is necessary to understand the timing of influenza seasonal epidemics.

Objectives

Our main objective was to determine whether influenza occurs in seasonal patterns in the American tropics and when these patterns occurred.

Methods

Publicly available, monthly seasonal influenza data from the Pan American Health Organization and WHO, from countries in the American tropics, were obtained during 2002–2008 and 2011–2014 (excluding unseasonal pandemic activity during 2009–2010). For each country, we calculated the monthly proportion of samples that tested positive for influenza. We applied the monthly proportion data to a logistic regression model for each country.

Results

We analyzed 2002–2008 and 2011–2014 influenza surveillance data from the American tropics and identified 13 (81%) of 16 countries with influenza epidemics that, on average, started during May and lasted 4 months.

Conclusions

The majority of countries in the American tropics have seasonal epidemics that start in May. Officials in these countries should consider the impact of vaccinating persons during April with the Southern Hemisphere formulation.

Reviews

There are no reviews yet.