Human networks of acquaintances, computer networks like the Internet, and interacting protein networks in the body, all share a characteristic layout: most of the elements have only a few links to others, while a few individuals have a very large number of links. [...]

The idea is to randomly choose, say, 20% of the individuals and ask them to name one acquaintance; then vaccinate those acquaintances. Potential super-spreaders have such a large number of acquaintances that they are very likely to be named at least once, the researchers found. On the other hand, the super-spreaders are so few in number that the random 20% of individuals is unlikely to include many of them.

Using the team's vaccination strategy, a disease can be stopped by vaccinating less than 20% of the individuals, in some cases, according to their computer model of a human population. The method can also be tweaked: if a larger sample is asked for names, and those named twice are vaccinated, the total number of vaccinations required can be even lower.