Pandemic influenza vaccination: Lessons learned from Latin America and the Caribbean

Abstract

In April 2009, the World Health Organization (WHO) reported the emergence of a new influenza (H1N1) virus which led to the first pandemic declaration of the 21st century. Most countries in Latin America and the Caribbean (LAC) had a national preparedness plan in place at this time; however, the vaccination component of such plans was largely undeveloped. Nevertheless, countries were able to capitalize on the infrastructure of their immunization programs and widespread experience utilizing the seasonal influenza vaccine to prepare rapidly, developing H1N1 vaccination plans targeting individuals with chronic disease, pregnant women and health care workers, among others. In LAC vaccine was acquired through three mechanisms: the Pan American Health Organization's Revolving Fund, direct manufacturer purchase, and WHO donations. Vaccine access was not equitable both in quantity of vaccine available and timeless of vaccine availability. As of December 2010, an estimated 145 million doses had been administered in LAC. Despite high regional coverage, there were large variations in coverage at the national level; pregnant women had the lowest coverage, despite their high risk for morbidity and mortality. The number of severe adverse events reported in LAC was similar to those expected with the seasonal influenza vaccine. Risk communication was one of the key challenges countries faced, mainly due to concerns and misinformation spread regarding vaccine safety. Countries and the international community need to learn from the experiences gained during H1N1 vaccination in order to be better prepared for the next pandemic.

Factors associated with a successful expansion of influenza vaccination among pregnant women in Nicaragua

“…For instance, influenza vaccination coverage among pregnant women in the United States increased from around 10% in 2001–2002 season to 50% in 2010–2011 season [24]. The results from this study are consistent with high rates of vaccination among high-risk pregnant women in Nicaragua achieved during the 2009 influenza pandemic [12]. …”

“…During the 2009 pandemic, vaccination with monovalent pandemic (H1N1) influenza vaccine was extended to persons with chronic diseases and to women with high-risk pregnancies [11]. Nicaragua was among the Latin American countries with the highest coverage (88.1%) of pandemic influenza vaccination for women with high-risk pregnancies [12]. …”

Risk Factors for Severe Influenza A–Related Pneumonia in Adult Cohort, Mexico, 2013–14

“…The vaccination rate was substantially lower among patients who required MV compared with those who did not; the overall vaccination rate among hospitalized patients contrasts with the high vaccination rates reported recently in Mexico for high-risk groups (71.7%–101.9%) ( 11 , 12 ). The association between severe influenza infection and obesity has been increasingly documented since the 2009 pandemic ( 13 ).…”

Knowledge, attitudes and practices about influenza vaccination among pregnant women and healthcare providers serving pregnant women in Managua, Nicaragua

“…As of 2014, 29 out of 45 countries/territories in the Americas, including Nicaragua, prioritize pregnant women for influenza vaccination [18–21]. Despite this high rate of prioritization in the region, more work can be done to communicate these important messages.…”