The 1918–19 Influenza Pandemic in Boyacá, Colombia - Vol. 18 No. 1 - January 2012 - Emerging Infectious Disease journal - CDC
Volume 18, Number 1—January 2012
The 1918–19 Influenza Pandemic in Boyacá, Colombia
Suggested citation for this article
Quantitative analyses of age-specific death rates, transmissibility, and dissemination patterns of the 1918 influenza pandemic in the United States (1,2), Mexico (3), Peru (4), Japan (5), Europe (6,7), Taiwan (8), and Singapore (9) have shed light on the epidemiology of the most devastating pandemic in recent history (10). These studies revealed the pandemic’s unusual severity in young adults, occurrence in multiple waves, and higher transmission potential than that of seasonal epidemics (11). However, quantitative historical studies remain scarce for Latin America, Africa, and Asia, where our understanding of influenza disease patterns remains particularly weak.
AbstractTo quantify age-specific excess-mortality rates and transmissibility patterns for the 1918–20 influenza pandemic in Boyacá, Colombia, we reviewed archival mortality records. We identified a severe pandemic wave during October 1918–January1919 associated with 40 excess deaths per 10,000 population. The age profile for excess deaths was W shaped; highest mortality rates were among infants (<5 y of age), followed by elderly persons (>60 y) and young adults (25–29 y). Mean reproduction number was estimated at 1.4–1.7, assuming 3- or 4-day generation intervals. Boyacá, unlike cities in Europe, the United States, or Mexico, experienced neither a herald pandemic wave of deaths early in 1918 nor a recrudescent wave in 1920. In agreement with reports from Mexico, our study found no death-sparing effect for elderly persons in Colombia. We found regional disparities in prior immunity and timing of introduction of the 1918 pandemic virus across populations.
The emergence of the pandemic influenza A (H1N1) 2009 virus in Mexico (12,13) reinforced the need to understand the epidemiology of past pandemics in the Americas to inform preparedness plans. We therefore analyzed death patterns for the 1918 influenza pandemic in Boyacá, a rural area in central Colombia, where influenza seasonality is less defined than in temperate regions (14). By using archival records, we quantified the age-specific excess-death rates and transmission potential of the 1918–19 pandemic in Boyacá and compared these findings with those reported for other locations, especially Mexico City, Mexico.