Influenza Epidemic of 2009?

Swine influenza, a type A type of the influenza virus, has exploded in Mexico this past week. Traditionally it had been rare for this virus to infect humans, and only then with direct contact with pigs. However, in the recent cases there appears to be significant person-to-person transmission.

The symptoms are very similar to the common influenza strain: headaches, bodyaches, fevers. Vomiting has also been reported. The CDC says two flu drugs, Tamiflu and Relenza, seem effective against the new strain. Roche, the maker of Tamiflu, said the company is prepared to immediately deploy a stockpile of the drug if requested. Both drugs must be taken early, within a few days of the onset of symptoms, to be most effective.

What is frightening is the current spread of potential outbreaks. Reported smaller outbreaks have been seen in Kansas, New York City, and even as far as New Zealand (although those students reportedly were in Los Angeles recently). The Centers for Disease Control released a statement, that it is too late to contain the spread of the virus, regardless of how severe the spread is.

The test case for pandemics of course is the Pandemic of 1918. Commonly referred to as the Spanish flu, the virus ravaged Europe, Asia, and North America. To give estimates: 7 million people died in India (almost 3% of the population); approximately half a million in the U.S.; and an estimated 10 million through out Europe. Actual numbers of deaths from the pandemic are uncertain, be definitely more than 20 million people died within the year, and upwards of 100 million may have perished from the virus from March 1918 to June 1920. That was much more than perished in the First World War.

No one is saying that even if this turns into a pandemic that it will be that severe. First of all, the 1918 influenza strain was highly virulent. It caused infections in almost half of the population, and then killed 2-10% of those infected. 'Normal' influenza at most kills 0.1% of those infected. We have no idea as of yet about the swine flu.

Additionally, two other factors are in our favor. Our expertise in epidemiology has advanced far beyond what we saw in the earlier parts of the last century. Health policy units from governments, such as the CDC and World Health Organization (WHO) can react in almost a moments notice. Additionally, we do have drugs to treat the virus, albeit imperfect drugs at that. For example, they must be taken early in the course of the illness to provide the maximum effect.

But one thing is for sure. A pandemic of influenza is sure to come, sooner or later. Scientists and physicians have been warning of this for decades. If you look historically, there have been influenza pandemics over and over again over the centuries. In fact, we had pandemics in 1957 and 1968...although much less severe than the massive devastation caused in 1918.

The real question is whether third world nations will appropriately respond, and have the facilities to respond. Unlike 1918, the most likely source of a future pandemic was always predicted to be farms...ala the swine flu. Close contact with such animals are rare in developed countries. So it is no surprise that the biggest fears of such pandemics come from Latin America, South America, China and India.

Medical professionals in the U.S. and elsewhere will have to be vigilant. Quick usage of antivirals, and distribution of those medications is necessary. And hopefully patients will respond to symptoms quicker than normal. Pandemics can be confronted, as long there is adequate response from government, health care providers, and the public.