The CDC and WHO have been warning us for years - the world is overdue for another flu pandemic. Below is a brief history of flu pandemics and as we look at their frequency, it appears that we are overdue for another serious outbreak:
An influenza pandemic is an epidemic of an influenza virus that spreads on a worldwide scale and infects a large proportion of the human population. In contrast to the regular seasonal epidemics of influenza, these pandemics occur irregularly, with the 1918 Spanish flu the most serious pandemic in recent history. Pandemics can cause high levels of mortality, with the Spanish influenza being responsible for the deaths of over 50 million people. There have been about 3 influenza pandemics in each century for the last 300 years. The most recent ones were the Asian Flu in 1957 and the Hong Kong Flu in 1968.
Influenza pandemics occur when a new strain of the influenza virus is transmitted to humans from another animal species. Species that are thought to be important in the emergence of new human strains are pigs, chickens and ducks. These novel strains are unaffected by any immunity people may have to older strains of human influenza and can therefore spread extremely rapidly and infect very large numbers of people. Influenza A viruses can occasionally be transmitted from wild birds to other species causing outbreaks in domestic poultry and may give rise to human influenza pandemics. 
The World Health Organization (WHO) warns that there is a substantial risk of an influenza pandemic within the next few years. One of the strongest candidates is a highly pathogenic variation of the H5N1 subtype of Influenza A virus. As of 2006, prepandemic influenza vaccines are being developed against the most likely suspects which include H5N1, H7N1, and H9N2. LINK
A swine flu outbreak that originated from Mexico has all of the elements of a potential pandemic; the CDC and WHO are monitoring this outbreak closely:
Because of the situation, the World Health Organization planned to consider raising the world pandemic flu alert to 4 from 3. Such a high level of alert — meaning that sustained human-to-human transmission of a new virus has been detected — has not been reached in recent years, even with the H5N1 avian flu circulating in Asia and Egypt, and would “really raise the hackles of everyone around the world,” said Dr. Robert G. Webster, a flu virus expert at St. Jude Children’s Research Hospital in Memphis. LINK
There were indicators early-on which distinguished this flu mutation as being extremely dangerous and raised the alarms at the World Health Organization and the CDC. Mexico’s flu season is usually over by this time of year, however, there was an unusual spike in flu cases, and unlike common flu varieties that strike the young and elderly the hardest - this strain of flu attacked individuals that were fairly young and in good health, mimicking the 1918 Spanish Flu Pandemic:
Mexico’s flu season is usually over by now, but health officials have noticed a significant spike in flu cases since mid-March. The W.H.O. said there had been 800 cases in Mexico in recent weeks, 60 of them fatal, of a flulike illness that appeared to be more serious than the regular seasonal flu. Mr. Córdova said Friday that there were 1,004 possible cases.
Still, only a small number have been confirmed as cases of the new H1N1 swine flu, according to Gregory Hartl, a W.H.O. spokesman. Mexican authorities confirmed 16 deaths from swine flu and said 45 others were under investigation, most of them in the Mexico City area. The C.D.C. said that eight nonfatal cases had been confirmed in the United States, and that it had sent teams to California and Texas to investigate.
“We are worried,” said Dr. Richard Besser, the acting head of the C.D.C. “We don’t know if this will lead to the next pandemic, but we will be monitoring it and taking it seriously.”
There is no point in trying to use containment measures in the United States, he said, because the swine flu virus has already appeared from San Antonio to San Diego, without any obvious connections among cases. Containment measures usually work only when a disease is confined to a small area, he said. MUCH MORE
The CDC states there is no necessity for “Containment measures” because the disease has already appeared “from San Antonio to San Diego.” I disagree. There’s certainly no need (yet) for extreme measures within the United States, however, increasing our border security may protect us from a potential influx of illegal aliens that are attempting to escape the origins of the outbreak. If this morphs into the next deadly flu pandemic, where would you prefer to get sick, in Mexico or the United States?
One situation that bears close scrutiny exists in New York City:
In New York City, health officials say about 75 students at a Queens high school have fallen ill with flu-like symptoms and testing is under way to rule out that is the same strain of swine flu found in Mexico. Results could take several days. LINK
I found the above except in another informative article that appeared on Yahoo News:
Fear, anger and fatalism over swine flu in Mexico