Kevin Bacon Meets Medical Science

In Scientific American: ‘Six Degrees of Immunization’ Strategy Proposed, I learned of an interesting way of more efficiently providing group immunization to large populations.

The concept is based on a growing understanding of social networks. The basic idea is that social networks consist of an unequal distribution of connections between members of the group. If the distribution was equal, we would each know the same number of people. In reality, however, there is a wide variation in the number of connections between people, with some of us having more connections than others. These highly networked individuals are referred to by different names - I shall use “super-nodes”.

There has been some interesting research into this phenomenon from a social science perspective, but now it is being used for medical research as well.

The idea expressed in the article is that these highly networked individuals are more likely to spread infectious diseases due to their contact with a greater number of people. By immunizing these super-nodes against an infectious disease, you can prevent a large percentage of transmissions with a relatively small number of vaccinations. You could then “fill in the gaps” by immunizing other people when time and resources allow.

An extension of this idea could involve using inactivated vaccines. An inactive (or attenuated) vaccine consists of live organisms that are incapable of causing disease. Because the organism is living, it is possible for it to spread to other individuals, just like any other infectious disease. It can then confer immunity to the newly “infected” person. By immunizing these super-nodes, you could spread immunization to a larger percentage of the population with fewer initial vaccinations, as compared to randomly administering vaccines.

There has been some quite interesting research into social networks recently (or perhaps I am simply becoming more aware of the available research). It is even being used to develop new business ideas, such as Friendster and LinkedIn. I am sure there are more interesting ideas awaiting us as this research continues…

Related Links:

Scientific American: E-mail Study Corroborates Six Degrees of Separation

Scientific American: Scientists Say Mass Vaccination Is Best Response to a Smallpox Attack

Scientific American: On average, how many degrees apart is any one person in the world from another?

Scientific American: Granting Immunity

Small World Research Project