The last decade or so has seen the emergence of two new infl uenza A viruses which have a different epidemiolgical and behavior pattern. The H5N1 virus has remained mainly an avian virus with human spread being limited and occuring only in persons coming in close contact with infected or dead poultry. The virus is however lethal causing a very high mortality. The pandemic 2009 infl uenza A (H1N1) virus on the other hand has emerged as a new human virus with the ability for effi cient human to human spread. Within a span of less than 6 months this virus has spread to more than 191 countries and emerged as the fi rst pandemic virus of this century. Fortunately, this virus causes a low mortality and hopefully this pandemic will be as mild as the last two infl uenza pandemic that occurred in 1957 and 1968. The fear that this virus may become more virulent and lead to a more severe pandemic as occurred in 1918 still exists. We therefore need to be vigilant and prepared if this happens in subsequent waves. Lessons learned from the 1918–1919 influenza pandemic The 1918 influenza pandemic was one of the most virulent strains of influenza in history. Phylogenic evidence of the novel H1N1 strain of influenza discovered in Mexico last spring (2009) links it to the 1918 influenza strain. With information gained from analyzing viral genetics, public health records and advances in medical science we can confront the 2009 H1N1 influenza on a global scale. The paper analyses the causes and characteristics of a pandemic, and major issues in controlling the spread of the disease. Wide public vaccination and open communication between government and health sciences professionals will be an essential and vital component in managing the 2009 H1N1 pandemic and any future pandemics. The infl uenza pandemic of 1918 is generally ranked second only to the 14th century "Black Death" plaque in terms of relativity and absolute mortality. [1] In fact, the death toll of the First World War failed to infl ict the human casualty rate that the 1918-1919 Infl uenza Pandemic did. Little progress has been made toward understanding the condition responsible for the extreme virulence of the "1918 type," and/or the conditions necessary to prevent the reappearance of this infl uenza. Unlike the typical "fl u" that strikes the very young, chronically ill and the elderly, this fl u would attack and kill healthy young adults. Taubenberger [2] reported that deaths resulting from the infl uenza and pneumonia for the 15-34-year-old cohort were 20 times higher in 1918 than any previous time, and 99% of excess deaths among people under 65 years of age [3] This strain of infl uenza killed so many people that it reduced the life expectancy of the United States with ten years during its course.