Researchers around the world are focusing on the H1N1 influenza-A virus that is suspected in the death of nearly 200 people in Mexico and sickened hundreds of others around the world. While some researchers look to produce a vaccine to halt the disease, others are looking to understand the nature of the virus in order to come up with better treatments and prevention measures.

At the University of Texas Medical Branch, known as UTMB, and the Galveston National Laboratory, located on campus, some of the world's top disease experts are following the spread of the new flu virus and pondering its origins as well as its impact. One of them is Thomas Ksiazek, who spent 17 years at the U.S. Center for Disease Control and Prevention in Atlanta before coming to UTMB.

He says much will be learned by doctors working in the effected areas in Mexico, where the epidemic started, and in other nations where cases have been identified.  One of the mysteries they are investigating is why so many healthy people in the prime of their lives have died from this flu. Ksiazek says evidence from past influenza outbreaks indicates that a strong immune system trying to fight off the infection may actually end up killing the person infected.

"The virus sort of over-stimulates the immune system that is strongest in that segment of the population and that over-stimulation leads to an over-reaction that is actually harmful, that actually acts against you in the instance of infection," he said.

Most of the fatalities from this flu have resulted from pneumonia, a condition in which the lungs fill with fluid, which could have been released by the person's immune system in an effort to defeat the infection.

Some business leaders and citizens in Mexico and the United States complain that shutting down government services and public venues will hurt poor families and disrupt the economy in general, but Ksiazek says health officials and government leaders are doing the right thing.

"There are, certainly, economic consequences for taking those actions, but what they are trying to avoid are the larger consequences of a whole lot of sick people in the population that are going to take it to an even higher order of transmission and also overburden the medical and other systems and shut down the other components of our economy," he said.

The UTMB virus expert says such broad measures can be effective, but that ordinary citizens must also do their part.  For example, he says the closing of schools may not work as planned if many students get together in other venues like shopping malls and parks.

"We are not sending the kids home from school so that they can gather at the mall, but rather they are expected to stay at home and not communicate with each other and, therefore, reduce the potential for the virus to bridge from one individual to another," he said.

Ksiazek says closings may not have to last more than a few weeks since a virus introduction coming this late in the northern hemisphere flu season is not likely to linger in one place.

"It comes and then goes and then pops up in other places, where they then suffer the same course of increasing number of people effected and then it moves on to another place," he added.

He says the ability of the virus to travel worldwide and to mutate makes it all the more important that scientists develop a vaccine in the coming months. The vaccine will not help anyone currently ill from the flu or exposed to it, but he says it may help mitigate an even stronger epidemic later this year or early next year.

Ksiazek says people living in areas where the flu has taken hold can protect themselves to some extent by wearing face masks, although these do not offer full protection from airborne infection. He says the most important measure is frequent washing of hands and avoidance of touching the face with the hands. He says anti-viral drugs can be effective in reducing the impact of the flu, but he cautions people not to take such drugs if they do not already have the illness, since over-use of these medicines could reduce their effectiveness.