Flu Patch

Influenza
Influenza (the flu) is a type of viral respiratory illness. The virus is transmitted from one person to another through contact with contaminated respiratory droplets (like in a sneeze or “germy” handshake). Once a person is infected, it takes about one to three days for symptoms to appear. Common signs include: fever, chills, cough, sore throat, headache, nasal congestion, runny nose, body aches, and extreme fatigue.

The National Institute of Allergy and Infectious Diseases reports about 5 to 20 percent of Americans get the flu each year. Flu season typically occurs during the late fall to winter months. As of February 12, the CDC reports widespread flu activity has occurred in 37 states.

Most people recover from the flu within a week, but weakness and fatigue can last for weeks. People over 65, children younger than two and patients with immune compromising illnesses are at risk for developing severe complications from the flu, like ear or sinus infections, bacterial pneumonia or worsening of underlying medical problems. Each year, more than 200,000 Americans are hospitalized for flu complications and an average of 23,600 people die.

Flu Vaccination
People can reduce their risk for getting the flu by frequently washing their hands, drinking plenty of fluids, maintaining a healthy lifestyle and staying away from those who have flu symptoms.

Another important way to reduce flu risk is through a vaccine. Because different strains of the flu circulate each year, a new vaccine is made annually. This year’s vaccine provides protection against the H1N1 virus, the H3N2 virus and one influenza B virus (Brisbane/60/2008-like). Health experts say everyone 6 months and older should get a flu shot every year. It is especially important for those who are at high risk of flu complications and their caregivers, to get the shot.

The traditional flu vaccine is given in the form of an injection. It is made with killed viruses. The newer, nasal flu vaccine is made from live, but weakened flu viruses. It is only currently approved for healthy people between 2 and 49. The nasal flu vaccine also can’t be given to pregnant women.

Microneedles
Many people dislike getting the flu shot because of the pain of the injection. Researchers are now working on other ways to deliver the vaccine. One of those methods is the use of microneedles, an array of very thin, short needles placed onto the skin in the form of a patch.

Scientists at Georgia Institute of Technology and Emory University in Atlanta, are working on microneedles made from a polymer, called poly-vinyl pyrrolidone, that can dissolve in bodily fluids. Freeze-dried flu vaccine is mixed in the polymer before the needles are molded. When the microneedle patch is placed on the skin, the tiny needles dissolve, releasing the flu vaccine into the skin. The microneedles are so small, they cause little to no pain when placed on the skin.

Emory Researcher Ioanna Skountzou, M.D., says the skin is an ideal receptor for the vaccine because it contains a significant number of immune cells. Thus, the vaccine gets targeted right into the immune system, rather than injected into a muscle, where it has to work its way into the circulatory system. In fact, preliminary research suggests the microneedle flu patch may provide stronger, longer-lasting immunity to the flu than a traditional vaccine.

Mark Prausnitz, Ph.D., Researcher with Georgia Institute of Technology, says another advantage of the dissolving microneedles is that there are no needles remaining that can cause injury or require special disposal. Once the needles are dissolved, the patch backing can be removed and discarded.

It will be several years before a real patch will be available for use. Prausnitz says, ideally, consumers will eventually be able to purchase the flu patch at a local drug store and apply it themselves. Ultimately, the patch may be used to deliver other vaccines, as well. The patch could especially valuable in third world countries because vaccines could be delivered very easily.

AUDIENCE INQUIRYFor general information on the flu or flu vaccination:
Centers for Disease Control and Prevention, http://www.cdc.gov
Flu.gov, http://www.flu.gov
National Institute of Allergy and Infectious Diseases, http://www.niaid.nih.gov

BIBLIOGRAPHYKim, Yeu-Chun, et al., “Enhanced Memory Responses to H1N1 Influenza Vaccination in the Skin Using Vaccine Coated-Microneedles,” Journal of Infectious Diseases, January 15, 2010, Vol. 201, No. 2, pp. 190-198.

Kim, Yeu-Chun, et al., “Improved Influenza Vaccination in the Skin,” Vaccine, November 2009, Vol. 27, No. 49, pp. 6932-6938.

Prausnitz, Mark, et al., “Microneedle-based Vaccines,” Current Topics in Microbiology and Immunology, 2009, Vol. 333, pp. 369-393.

Quan, Fu-Shi, et al., “Intradermal Vaccination with Influenza Virus-like Particles by Using Microneedles Induces Protection Superior to that with Intramuscular Immunization,” Journal of Virology, August 2010, Vol. 84, No. 15, pp. 7760-7769.

Sullivan, Sean, et al., “Dissolving Polymer Microneedle Patches for Influenza Vaccination,” Nature Medicine, August 2010, Vol. 16, No. 8, pp. 915-920.

Temte, Jonathan, M.D., Ph.D., and Jacob Prunuske, M.D., “Seasonal Influenza in Primary Care Settings,” Wisconsin Medicine Journal, August 2010, Vol. 109, No. 4, pp. 193-200.