Researchers from the Harvard Medical School and the Dana-Farber Cancer Institute have identified new human antibodies that inactivate influenza, not just bird flu, but any of the seasonal influenza viruses that affect people in the winter.

This new scientific discovery will hopefully lead to medications to fight the flu as well as a vaccine that would not have to be changed every year because it could target a broad range of flu strains.

It is a new target, new mechanism and new human antibodies that have been found. The antibodies recognize a new part of the influenza virus and inactivate the virus by a new mechanism. These antibodies can be used as drugs, which is a commonplace in treatment for such cancers as colon, breast and lymphoma.

Drugs developed from the newly identified antibodies could, in combination with other treatments, prevent or treat certain avian and seasonal flu strains and could also lead to the development of a long-lasting flu vaccine.

Such drugs would be used in the same way antiviral medications, such as Tamiflu, are used today. Antivirals generally are given to prevent a virus after exposure or to treat a virus once it develops. This year, however, the commonly circulating H1 strains of the influenza virus are resistant to Tamiflu. Resistance develops because a drug targets the large head of the flu virus, but the virus is able to quickly mutate, making it resistant to medications and vaccines. This is why a new seasonal flu vaccine is needed every year.

The newly identified antibodies attack the stem of the virus, which is more resistant to change and "does not change amongst the various influenza viruses.

If a vaccine could be developed to target this area in the virus, it might offer long-term protection.

The researchers identified 10 monoclonal antibodies that can bind with a protein in flu viruses that is needed to allow the virus to enter other cells. The antibodies effectively blocked the ability of the virus to enter other cells.

In addition, the researchers showed that the antibodies protected mice from getting the N5N1 avian flu, which many scientists believe could cause a worldwide flu pandemic. The new monoclonal antibodies were also effective against the 1918 flu strain as well as against a number of common seasonal flu strains.

Drugs using these antibodies could be in human clinical trails as early as 2011.