This year's strain of the influenza virus may just prove to be lethal to children this year.  And while the annual infection has only just begun, three children in Minnesota have already died of complications from a very potent strain of the influenza virus, health officials say.

Seven other children were also placed in the intensive care unit of the Children's Hospital in St. Paul, according to a recent report from the Minnesota Health Department. Dr. Pritish Tosh, an infectious disease physician with the Mayo Clinic, and a member of the Mayo vaccine research group, says this year's strain of the virus is far more dangerous than past strains, and could even become a life-threatening illness for children.

"The virus can enter the blood stream and then the brain, creating severe respiratory symptoms including shortness of breath and a very high fever," Tosh says. He went on to state that even in a healthy child, the body can overcompensate, sending white blood cells into the lungs.  This can overwhelm the body and cause life-threatening ramifications. "If the body's reaction to the virus is too vigorous, this can cause as much damage as the virus itself."

Strains of influenza are classified by the molecule types outside the virus particle.  To be more specific, there are 17 different types of hemagglutinin, or H particles that allows the virus to bind to cells, and  there are nine different types of neuraminidase, or N particles that allow the virus to spread. This years variant, H3N2, has thus far been responsible for ninety percent of the cases already seen this flu season, and has also proven to be a particularly serious variant of the virus.

H3 subtypes tend to be the most serious, leading to more hospitalizations and deaths, especially for children and the elderly, including others who have compromised immune systems.  This year's strain is not well-matched to what was predicted by physicians, making the current vaccine an imperfect match.

"Some would speculate that this means the vaccine won't work as well, but that has not been proven," Tosh says. "You should still get your flu shot because it's the best protection we have."

Influenza, otherwise known as the flu, is a contagious respiratory illness caused by influenza viruses, and it can cause mild to severe illnesses. Serious outcomes of flu infection can result in hospitalization or even death.  Some people, such as the elderly, young children, and people with certain health conditions or depressed immune systems, are at high risk for serious flu complications. And while doctors say that this strain is likely to still run rampant, the best way to prevent infection is by getting vaccinated each year, and making sure to wash hands habitually.