Illustration: Sarah Grillo/Axios
What's new: Scientists announced Wednesday they have successfully developed three key advances toward a possible pandemic flu vaccine — and it's one that could eventually be delivered to your doorstep via the mail, and be self-administered.
Why it matters: One of public health officials' greatest fears is another flu pandemic that could kill millions. It's not a question of if another one occurs, but rather when. Pandemics can kill large amounts of people worldwide. The largest influenza pandemic, known as the Spanish flu, occurred 100 years ago. It killed at least 50 million people.
- As pointed out recently by Bill Gates, whose foundation has prioritized the development of a universal flu vaccine, the next global pandemic could have the potential to kill nearly 33 million people in six months.
- Besides the need to rapidly develop vaccines that could cover whatever the pandemic strain is (or the creation of a universal flu vaccine to cover all the possible influenza strains), medical personnel need to consider the separate challenge of how to distribute such a vaccine.
What they did: In the study, published in Science Advances, the team took three major new steps.
1. They developed a short, hollow microneedle that penetrates only the top layer of the skin rather than the muscle, allowing it to be self-administered.
- "The idea of a self-administration has been very important with [the development of] a pandemic flu vaccine," study co-author Darrick Carter told Axios.
- Infectious Disease Research Institute's Carter says they plan to develop bandages or patches with an array of dissolvable microneedles to make a relatively painless and easy-to-administer vaccine that could be mailed in an envelope or distributed for free outside grocery stores.
- Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases who was not part of the study, tells Axios the technological advances are important. "This gadget allows you to accurately give the vaccine to yourself."
2. They produced a noninfectious flu vaccine that would protect against the very deadly Indonesia H5N1 flu virus in an expedited process. It manufactures the vaccine in 3–4 weeks versus the normal 4-6 months needed for egg-based vaccines.
- They used a tobacco plant-based system developed by Canadian company Medicago under a DARPA program that produced 30 million doses in 30 days, Carter says.
- It's a recombinant vaccine, which means it contains virus-like particles that are not contagious and could be safely transported through the mail.
- However, Fauci points out that the vaccine itself isn't a true pandemic vaccine because no one knows if a novel H5N1 strain will pop up again. In the meantime, he says multiple organizations continue their efforts to develop a universal vaccine.
3. They added an immune booster to the vaccine, called an adjuvant, which was deemed safe in their 100 person trial — making it the first one deemed safe for intradermal use.
- The adjuvant has been shown to boost the response rate of other types of vaccines, and it proved very effective here too, Carter says.
- Fauci agrees: "This showed remarkable enhancement of vaccine responses."
- Carter says the effectiveness is due to the combo of the adjuvant and the intradermal shot into the skin — which he says can be more effective than an intramuscular vaccine, since 70% of a person's immune system is in their skin and lungs.
Next step: Carter says they will aim for larger human trials and the creation of the vaccine into a bandage with dissolvable microneedles.
"If we can get it into the intradermal system, we'll have a significant enough response to trigger the immune system," Carter says.