WHO declaration points to global spread, not severe impact, of influenza outbreaks

Washington, D.C., 12 June 2009 (PAHO)—For the countries of Latin America and the Caribbean, the declaration of a full-fledged A (H1N1) influenza pandemic means they should be on the alert for new cases but should not necessarily expect a dramatic increase in severe illnesses or deaths, a Pan American Health Organization (PAHO) spokesman said today.

"Moving to phase 6 does not imply that there will be increases in rates of deaths or severe illness," said Jon Andrus, a senior PAHO medical epidemiologist and technical advisor for immunization. So far, "most people have relatively mild illness and recover without medication."
Moreover, "Hospitals and health care systems in most countries generally have so far been able to cope with the numbers of people seeking care, although in some localities, we do know that some facilities and systems have been stressed," he said.

The comments were part of a press briefing held at PAHO headquarters today, a day after the World Health Organization (WHO) declared that the spread of influenza A (H1N1) was now at the level of a pandemic. The change in the WHO alert level, from phase 5 to phase 6, was made because evidence points to sustained community transmission of the virus in at least two WHO regions.

The phase change indicates global spread, but it does not reflect any change in the severity of illness or impact of the disease, Andrus noted. It does mean that countries that have not yet had cases should expect to begin seeing them.

WHO continues to recommend no restrictions on travel and no border closures, saying that these would be highly disruptive of social and economic life but would do little to slow the spread of A (H1N1).

"National efforts should focus primarily on mitigating the health and social impact of the virus, rather than on attempts to contain transmission of the disease," Andrus said.

The new virus, which emerged in Mexico and the United States in April, has now spread to 74 countries, 26 of them in the Americas, with more than 29,000 confirmed cases and 145 deaths.

Because A (H1N1) is already spreading widely in the Americas, the declaration of a pandemic does not notably alter the situation for PAHO member countries.

"For the last 40 days or so, we've been operating under emergency conditions," Andrus said, speaking of PAHO and health authorities in its member countries. "I think phase 6 allows us to take a step back and reflect on what we need to do over time. Most pandemics last years, so this is not a sprint, it's a marathon."

The situation could change, he added, depending on how the virus evolves over time and what impact is has in different countries and subregions. Countries in the Southern Hemisphere, for example, are just beginning their regular flu season.

Moreover, "most pandemics come in waves, so it behooves countries to be on the alert for a second wave."

Also uncertain is what impact the virus will have on countries and communities with limited resources or a high proportion of vulnerable populations, such as indigenous groups. In these cases, "we do not know how this virus is going to react. Preliminary evidence suggests that the virus exerts more damage," Andrus said.

Current impact

So far, in nearly all areas where A (H1N1) has infected large numbers of people, the majority of cases have occurred in people under age 25. "This is something we don't usually see with seasonal influenza," said Andrus.

Most cases of serious disease and deaths from the virus have occurred in adults between 30 and 50 years old, unlike with seasonal influenza, which causes deaths mostly in the elderly.

In some countries, around 2 percent of A (H1N1) cases have developed severe illness, rapidly progressing to life-threatening pneumonia. Between one-third and one-half of severe and fatal cases have been previously healthy young and middle-aged adults. The other one-half to two-thirds of severe cases have been people with underlying chronic conditions such as asthma, cardiovascular disease, diabetes, autoimmune disorders, and obesity. Pregnant women are also at increased risk of complications.

A vaccine against A (H1N1) is expected to be available as early as September or October. PAHO, through its 30-year-old Revolving Fund for vaccine purchases, and WHO are working with countries and manufacturers to make sure the vaccines will be available and affordable to low- and middle-income countries. WHO is also convening experts to address such questions as which risk groups should get the new vaccine, given that it will only be available in limited supply.

Until a vaccine becomes available, Andrus urged people to continue to wash their hands frequently, cover sneezes and coughs with a tissue, and stay home from work or school and delaying travel when ill.

People who are ill should seek medical attention if they have a fever over 100.4 F (38 degrees C), if they experience shortness of breath or difficulty breathing, or if a fever continues for more than three days. Medical care should be sought for any child who has fast or labored breathing, continuing fever or convulsions, or who is confused, unconscious, or difficult to awaken.

PAHO collaboration in the field

PAHO is helping its member countries prepare for and respond to A (H1N1) by mobilizing multidisciplinary teams of experts who travel to the countries to advise national health authorities on epidemiology and situation monitoring, infection control and case management, and virology and laboratory issues, including testing for the virus.

So far, PAHO has mobilized teams to Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Panama, Bolivia, Paraguay, and Chile. Additional teams are expected to travel to Ecuador and Uruguay in the coming weeks. Experts for the teams are recruited through the Global Outbreak and Response Network (GOARN). PAHO's principal partners in GOARN include the U.S. Centers for Disease Control and Prevention (CDC), the CDC's Regional Office for Central America and Panama (CDC-CAP), the Public Health Agency of Canada, the National Institute of Health of Portugal, the Ministry of Health of Spain, the University of Valparaiso in Chile, and the Seattle-based global health nongovernmental organization PATH.

In addition, PAHO has held frequent consultations with member countries' health authorities and has facilitated information sharing, for example, to facilitate the development and updating of guidelines for clinical management of patients with A (H1N1).

Before the current outbreaks, PAHO had been worked intensively with its member countries to draft and implement pandemic preparedness plans and to develop their capacities for surveillance and reporting of infectious disease outbreaks.
"We have made an investment in pandemic preparedness in the past five years, and this is now very beneficial as we track cases globally," said Andrus. "We have a good idea of its spread because of good surveillance and investigation. However, the virus can change, and we will not know ahead of time. We have to guard against complacency, and countries need to strike the right balance."

Andrus noted that the public reaction to a phase change should not be a major concern.

"It is normal for communities to be anxious. There is a normal period of adjustment during which the public gets used to this new threat. But countries of the Americas have already been in the process of doing this."

He urged health authorities to "make active communications a part of their strategic response by providing accurate and up-to-date information on issues such as pandemic activity and actions being undertaken by the government."


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