A technology that could eventually see every childhood vaccine delivered in a single injection has been developed by US researchers.
Their one-shot solution stores the vaccine in microscopic capsules that release the initial dose and then boosters at specific times.
The approach has been shown to work studies on mice, described in the journal Science.
The researchers said the technology could help patients around the world.
Current childhood immunisations include:
- Diphtheria, tetanus, whooping cough, polio, Hib and hepatitis B at eight, 12 and 16 weeks.
- Pneumococcal jab at eight weeks, 16 weeks and one year
- Men B vaccine at eight weeks, 16 weeks and one year
- Hib/Men C vaccine at one year
- Measles, mumps and rubella at one year and three years and four months
A team at Massachusetts Institute of Technology has designed a new type of micro-particle that could combine everything into a single jab.
The particles look like miniature coffee cups that are filled with vaccine and then sealed with a lid.
Crucially, the design of the cups can be altered so they break down and spill their contents at just the right time.
One set of tests showed the contents could be released at exactly nine, 20 and 41 days after they were injected into mice.
Other particles that last for hundreds of days have also been developed, the researchers said.
The approach has not yet been tested on patients.
Robert Langer, from MIT, said: "We are very excited about this work.
"This could have a significant impact on patients everywhere, especially in the developing world."
The work differs from previous attempts, which slowly released medicines over a long period of time.
The idea is the short, sharp bursts of vaccine more closely mimic routine immunisation programmes.
Fellow researcher Kevin McHugh said: "In the developing world, that might be the difference between not getting vaccinated and receiving all of your vaccines in one shot."