Health Officials On Alert For Influenza Pandemic
According to health experts, every 50 years an influenza epidemic breaks out and if the virus were to reach Costa Rican shores, health officials estimate some 600.000 may be infected, possibly killing between 2.000 and 6.000 in three months.

Costa Rica has had measures in place since 2005, uniting a group of experst working in different areas of prevention, with four established sentinel posts who are keeping a close eye on the situation.

In addition, hospitals and medical professionals are receiving training in the event the influenza epidemic hits the country.

Influenza, commonly known as the flu, is an infectious disease of birds and mammals caused by an RNA virus of the family Orthomyxoviridae (the influenza viruses).

In humans, common symptoms of influenza infection are fever, nausea, vomiting, sore throat, muscle pains, severe headache, coughing, and weakness and fatigue.[1] In more serious cases, influenza causes pneumonia, which can be fatal, particularly in young children and the elderly.

Sometimes confused with the common cold, influenza is a much more severe disease and is caused by a different type of virus. Similarly, the unrelated gastroenteritis is sometimes called "stomach flu" or "24-hour flu".

Typically, influenza is transmitted from infected mammals through the air by coughs or sneezes, creating aerosols containing the virus, and from infected birds through their droppings.

Influenza can also be transmitted by saliva, nasal secretions, feces and blood. Infections occur through contact with these bodily fluids or with contaminated surfaces.

Flu viruses can remain infectious for about one week at human body temperature, over 30 days at 0 °C (32 °F), and indefinitely at very low temperatures (such as lakes in northeast Siberia). They can be inactivated easily by disinfectants and detergents.

Flu spreads around the world in seasonal epidemics, killing millions of people in pandemic years and hundreds of thousands in non-pandemic years.

Three influenza pandemics occurred in the 20th century and killed tens of millions of people, with each of these pandemics being caused by the appearance of a new strain of the virus in humans. Often, these new strains result from the spread of an existing flu virus to humans from other animal species. Since it first killed humans in Asia in the 1990s, a deadly avian strain of H5N1 has posed the greatest risk for a new influenza pandemic. However, this virus has not mutated to spread easily between people.

Experts recommend flu vaccinations, washing hands frequently and taking extra care when sneezing.