Pandemic (H1N1) 2009 regional update 09 Oct 2009

from Pan American Health Organization
Published on 09 Oct 2009 View Original
The information contained within this update is obtained from data provided by Ministries of Health of Member States and National Influenza Centers through reports sent to Pan American Health Organization (PAHO) or updates on their web pages.

I- Evolution of the pandemic

North America

Regarding WHO qualitative indicators (See Annex 1) for monitoring of the pandemic, the three countries in North America report widespread geographic spread. There was an increasing trend of respiratory disease in Canada and Mexico, while decreasing in the Unites States. The intensity of acute respiratory disease was low to moderate in Canada and high in Mexico and the United States. The impact on Health Services was low in Mexico and moderate in the United States

On its web page1, as of 8th October, Mexico reports increased activity of pandemic (H1N1) 2009 with the greatest number of cumulative laboratoryconfirmed cases in the Federal District, Chiapas, Yucatan, Jalisco, San Luis Potosi, Veracruz and Tamaulipas. When comparing against cases reported in the previous week (1st October), the greatest increases were observed in Durango, Morelos, Baja California Sur, and Puebla. It is important to note that Mexico is currently experiencing concurrent outbreaks of dengue and dengue hemorrhagic fever in several states.

In the United States, the influenza season began 12 weeks earlier than expected. The proportion of visits for influenza-like illness (ILI) has been above the baseline for EW 39 in all regions except two2 in the northeast. Regarding the geographical spread of the pandemic, 373 out of 50 states are experiencing geographically widespread activity (10 more than the previous week). Deaths attributed to pneumonia and influenza have now exceeded what is normally expected for this time of year. The United States has reported 12 cases of oseltamivir-resistant pandemic (H1N1) 2009

Canada has experienced an increase in national ILI consultation rate since EW37 which has been above expected levels. Multiple outbreaks were reported, especially in schools settings. The highest activity of respiratory disease has been reported in the province of British Columbia with 11 influenza outbreaks, and in the Northwest Territories where two outbreaks were detected in schools. Canada has reported two cases of oseltamivir-resistant pandemic (H1N1) 2009.


Cuba and Jamaica report widespread geographic spread while Bahamas and Dominica note regional spread and Saint Kitts and Nevis reported no activity. The trend of respiratory disease increased in most countries and the intensity of acute respiratory disease was high in Cuba and Dominica. The impact on health care services due to acute respiratory disease was both low and moderate.

Dominica has reported experiencing increased ILI activity and Saint Lucia reported influenza-associated outbreaks in the school setting during September.

Central America

Countries in this region reporting widespread geographic spread are Costa Rica, Nicaragua, and Panama, while in El Salvador the spread was regional. Trends in respiratory disease were decreasing or unchanged for all countries. The intensity of acute respiratory disease was mostly low or moderate while impact on heath care services due to acute respiratory disease was low in Guatemala, Nicaragua, Panama and mode rate in Costa Rica and El Salvador.

Belize reports experiencing a second wave of pandemic (H1N1) 2009 with increased ILI above expected levels for this time of year. Most patients are being seen in outpatient facilities with mild to moderate manifestations and the Districts of Belize, Cayo and Corozal mostly affected. Honduras also reports increased activity of influenza. Of note, El Salvador, Honduras, Nicaragua, Panama are detecting a recent increase in their cases of dengue fever as compared to the same time period last year. The current rainy season favors the co-circulation of influenza and dengue viruses.

South America

In the Andean regions of South America, geographical spread was widespread. The trend of respiratory wasmainly decreasing or unchanged and the intensity was low or moderate. The impact on heath services waslow in Bolivia, Colombia, and Peru and moderate in Ecuador and Venezuela.

Paraguay reported a different situation than the rest of the Southern Cone countries, as it experienced high intensity and moderate impact on health services. The rest of the Southern Cone countries presented low intensity and decreasing trend. In Chile, for example, of the 367,041 clinical cases and 12,252 confirmed cases since the beginning of the pandemic, only 121 clinical cases and two confirmed cases were detected in this week. Similarly, Argentina detected a decrease in hospitalizations for severe acute respiratory infection for the last ten weeks.

Summary of Last Week

- The intensity of acute respiratory diseases in North America was high in U.S. and Mexico and moderate in Canada.

- Central America experienced low or moderate intensity of acute respiratory diseases, with the exception of Belize that reported activity above what is expected.

- South America continues to report low or moderate activity of respiratory diseases.

- 99.1% of the influenza A viruses subtyped were pandemic (H1N1) 2009.

- 114 new confirmed deaths (3406 deaths accumulated in 25 countries)