A group of scientists developed a flu shot that doesn’t require to be injected. For the first time ever, researchers tested a flu vaccine patch in a human clinical trial and discovered that it delivered the same protection as a traditional shot with a needle. The development was dubbed microneedle patch.

Their findings were published Tuesday in the journal The Lancet. The researchers believe that not only needle-phobes who will benefit from this invention since public health experts and doctors hope the vaccine patches will help to increase the number of people who get immunized against the flu.

Image credit: Christopher Moore / CNN
Image credit: Christopher Moore / CNN

Seasonal influenza is a strain of the flu that kills over half a million people around the world each year, according to the World Health Organization. In the United States, the influenza death toll since 2010 has fluctuated between 12,000 and 56,000. However, only around 40 percent of American adults get flu shots.

Microneedle patches were tested and proved to be as effective as regular flu shots

Experts believe that one of the reasons why vaccination rates are low is because most people dislike getting traditional flu shots that involve needles. Some argue that vaccination rates are low due to the time and expense involved in getting a flu shot.

Now, a team led by Mark Prausnitz, a Georgia Tech engineer, has come up with an alternative method that involves “microneedles” instead of the traditional needles. These microneedles are so small that 100 of them, arranged on a patch, can fit under a thumb. However, they’re big enough to hold vaccine for three different strains of the flu.

“Microneedle patches have the potential to become ideal candidates for vaccination programs,” wrote the researchers.

The microneedle patch was tested in a randomized clinical trial led by Dr. Nadine Rouphael and colleagues at Emory University’s Hope Clinic in Decatur, Georgia. The clinical trial involved 100 volunteers who were randomly sorted into four groups.

Microneedles are so small that 100 of them, arranged on a patch, can fit under a thumb.  Image credit:  Georgia Tech / MedicalXpress
Microneedles are so small that 100 of them, arranged on a patch, can fit under a thumb. Image credit: Georgia Tech / MedicalXpress

Two of the control groups were vaccinated with the microneedle patch, which looks like a Band-aid and must be applied to the skin near the wrist for about 20 minutes. The procedure was so simple and straightforward that one group of participants was able to administer the patch themselves. In the other group, the patch was administered by healthcare professionals.

The researchers conducted analyses on the used vaccine patches and found that the microneedles dissolved during the 20 minutes they were in contact with the skin.

Most participants still were protected against the flu after six months

The third volunteer group received a traditional flu shot using a regular needle, while the fourth group got a patch that looked like the microneedle patch but contained a placebo.

The scientists checked in on the participants 28 days after their immunizations and discovered that flu antibody levels were “significantly higher” in the three control groups that got the actual flu vaccine than I the group that got the placebo.

Furthermore, the two groups who got the vaccine via microneedle patch had about the same antibody levels as the group who received the shot with a regular needle. The results also showed that volunteers who put the patches on themselves received the same protection as those whose patches were administered by health professionals.

The study also noted that after six months, at least 75 percent of participants in all three groups were still being protected.

Microneedle patches could mostly benefit people in low and middle-income countries

The traditional flu shot contained over 15 micrograms of antigens -which are the parts of the flu virus that trigger an immune response- to each of the three strains of flu that were tested in the study. The microneedle patches, however, contained a slightly smaller dose of antigens, regardless of whether the patches were administered by a health professional or a volunteer.

The researchers noted that none of the volunteers had serious side effects from the vaccines. The groups who received patches showed mild skin reactions that were not seen in the regular needle group, while the volunteers in that group were more likely to feel pain.

Overall, 70 percent of the participants who got microneedle patches said they’d rather use them again than get a regular needle shot or an intranasal vaccine. The paper authors said the study was a success on all fronts.

“Influenza vaccination with microneedle patches is well tolerated, well accepted, and results I robust immunological responses, whether administered by health care workers or by the participants themselves,” wrote the researchers.

However, they added that the patches would also have to succeed in larger studies before they could be put into wide use. The researchers noted that future versions of the patches would produce fewer skin side effects while delivering the same protection.

“These early findings suggest the emergence of a promising new option for seasonal vaccination,” said Katja Hoschler and Maria Zambon of Public Health England, according to the Los Angeles Times.

Researchers believe the biggest beneficiaries could be people in low- and middle-income countries, where traditional flu vaccines are usually hard to come by.

Source: Los Angeles Times