The term global health security has become more widely used in the past few years. And all indications are that this sub-specialty within global health will receive increasing attention in the future. Like many evolving concepts, there isn't a single clear definition of what global health security means. Therefore, I would describe the term global health security, as incorporating the following concepts. Preventing and responding to outbreaks and epidemics, health as an instrument in broader geopolitical issues, and preventing and preparing for bioterrorism. Given the cross border nature of these challenges, global health security is an essential element of global health diplomacy. For this course, we'll primarily discuss the issues related to outbreaks and epidemics, and we'll touch on geo-politics in the final lesson. Bioterrorism is a large subject into itself, so I'll leave that for another course. Let's start by looking on a brief history disease outbreaks that the world has faced over the past century. This slide gives a good overview of some of the biggest diseases to have emerged since the 1900s. In 1918, a major flu pandemic began crossing the globe eventually infecting 500 million people and killing between 50 and 100 million, which was between 3 and 5% of the world's population at the time. The outbreak actually first began in France, Germany, the UK, and the US. But this was during the first World War, and media coverage in these countries was often censored during this period. Therefore, when the disease hit Spain, which had a more liberal press, it received much more publicity, creating the perception that Spain was hit hard by the disease. Thus, giving way to this pandemic often being referred to as the Spanish Flu. The fact that this disease hit during the war when soldiers constantly traveled in large groups across borders and continents is considered a primary driver of why the disease spread so quickly. Another pandemic is HIV/AIDS, which was first identified as a disease in 1981. Although research suggests that the disease began in the Democratic Republic of Congo as early as the 1920s. It began to spread in epidemic proportions in the the late 1970s. WHO estimates that approximately 34 million people have died from AIDs. And today, there approximately 37 million people living with HIV AIDs with 70% of those infected living in Africa. The next pandemic we'll discuss Avian flu, is sometimes referred to by its technical name H5N1, and is a version of the flu that first appeared in birds. In 1997 the first human case of H5N1 was reported in Hong Kong and was believed to have been transmitted via poultry. According to the World Health Organization quote, since its widespread re-emergence in 2003 and 2004, this avian virus has spread from Asia to Europe and Africa and has become entrenched in poultry in some countries, resulting in millions of poultry infections, several hundred human cases, and many human deaths. Outbreaks in poultry have seriously impacted livelihoods, the economy, and international trade in effected countries, end quote. H5N1 remains concerning, because we're not clear on how the disease jumps from poultry to humans, and because of fears it could mutate to impact humans more easily. A final epidemic I will touch on is Severe Acute Respiratory Syndrome or SARS, which was first identified in 2003. It spread to more than two dozen countries, causing almost 8,100 cases and 774 deaths. Fortunately, the virus disappeared and has only been seen once since then. But the rapid spread across the world put public health officials on notice. We'll spend more time discussing Ebola in coming lessons. In addition to these diseases that have grabbed global attention, outbreaks of other emerging infections such as Hendra, Nepa, and Middle East Respiratory System, or MERS, have puzzled doctors and scientists. In summary, over the past two decades, there has been an increase in recognizing new, emerging infections. This has led to a growing focus on global health security, with the recognition that in our globally connected world no disease is more than a plane ride away. And the world needs to be much smarter in how we work together to prevent outbreaks from becoming epidemics. Now let's take a moment to review what we have learned so far.