Scientists are developing a needle-free vaccine, which targets the bacteria responsible for nearly one half of all ear infections, and gets absorbed through the skin via a small, dime-sized patch.
Researchers at Nationwide Children's Hospital in US found that when the experimental vaccine is applied to the outer ear, it appears to pack a one-two punch against nontypeable Haemophilus influenzae (NTHI).
It attacks key parts of the bacteria's defenses and kick-starts the body's own immune system to help clear out the infection.
This dual mechanism helps explain earlier animal research conducted by the team that showed the vaccine could be used as a either a preventative or a treatment for ear infections, which are commonly treated with antibiotics.
However, NTHI bacteria build biofilms, sticky protective covers that evade antibiotics and allow the bacteria to flourish in the middle ear, nasal passages and lungs to cause repeat infections.
"For a child, a non-needle vaccine has obvious benefits, but our research also shows that delivering the therapy through the skin sets off beneficial immune responses we might not see otherwise," said Laura Novotny, Chief Research Associate at The Research Institute at Nationwide Children's.
"There are kids that have seven or eight ear infections before their first birthday, and these chronic infections can cause language and developmental delays. To have an option that could help break the reinfection cycle and reduce antibiotic use is significant," said Novotny, who is also the co-author of the study published in journal Vaccine.
The experimental therapeutic appears to target key proteins used by the bacteria to build biofilms and cling to the cells lining the middle ear.
The investigators observed the vaccine helped the body mount a local defense that zeroed in on those proteins, and also rallied systemic molecular defense mechanisms that helped further eliminate the infection.
"We think it's the first time anyone has shown that a topical application of an agent can trigger both a local and systemic immune response against ear infections caused by NTHI," said Novotny.
"The patch could be truly impactful in developing countries, where costs for widespread vaccinations can be an issue," said Novotny.
"Syringes and trained medical professionals who can administer a vaccine can be expensive - but the patch could reduce material and resource costs significantly," Novotny added.
