It has been described as a ‘brilliantly bold’ initiative, as ‘audacious’, and a ‘game-changer’. This is the proposal by Mark Zuckerberg, principal shareholder in Facebook and his wife, Priscilla Chan, a pediatrician, to invest $3 billion in a program to cure all diseases by 2100. To be sure there is some small print. While the launch on 21 September was in front of a screen asking ‘Can we cure all diseases in our children’s lifetime?’, the actual text is a bit different. It is not that no-one will ever get sick but that all diseases will be treatable or at least easily manageable. The first major investment is in Biohub, an independent research facility in San Francisco, partnered with UCSF, Berkeley and Stanford. Prominent scientific cheerleaders like Francis Collins from NIH and David Baltimore, Nobel laureate and former president of Caltech, have endorsed the program.
Some perspective. A one-off $3 billion is not as much as it sounds. The US National Institutes of Health spends about $30 billion every year on biomedical research. However, a private initiative may be able to take more risks and support innovations that a public funder could sustain. It is not so bound by the inherent conservatism of peer review and public or political accountability. This brings its own dangers. Few biomedical scientists can resist the scent of large amounts of cash on the table. Why discourage a well-intentioned donor by asking hard questions or pointing to the potential pitfalls – which is what peer review is supposed to do.
In this case, the problems reflect the growing disconnection of biomedical research not only from the social sciences but also from important areas of fundamental biology. Put simply, the likes of Collins and Baltimore seem to have forgotten whatever they might once have learned about evolutionary theory.
The first thing to remember is that there are no such things as diseases in nature, merely interactions between organisms. ‘Disease’ is a label that humans use to describe a set of these interactions that affect us, and a few animal and plant species that we value, in ways that we consider to be negative. The application of this label in different times and places is part of the subject matter of philosophy, history, sociology and anthropology. The label is embedded in culturally specific ideas about the nature of deviance, and the attribution of responsibility for it. Clinical medicine, and the research that underpins it, are the way that important elements of contemporary global society happen to think about what are, and are not, valued states of the body. They are not eternal truths, although they may, pragmatically, be more effective than alternatives.
Evolutionary theory leads us to think about the nature of these interactions without the application of social or moral judgments. It underlines their dynamism. A popular misconception is that species evolve in isolation: changing against a static background. Evolution is more chaotic: in fact, it is better to think of all evolution as co-evolution. One organism’s advantage is a change in the environment for others. This change alters the conditions that have favored some traits and disfavored others. As different traits are encouraged, the environment changes for all of the organisms.
Antibiotics and bacteria are an obvious example. Antibiotics changed the environment for some bacteria. They eliminated many individual organisms – but those with resistant traits were left and reproduced. With many of their competitors eliminated, they were able to re-occupy the space emptied by the action of the antibiotic. Humans developed new antibiotics and the process was repeated – this is co-evolution at work in a contest that neither humans nor bacteria can ‘win’. At best there is a temporary advantage for one or the other.
It is here that we see the basic flaw in the Chan Zuckerberg program. Suppose, for example, that it were to succeed in eliminating one or more infectious diseases. The result is merely to empty a space in the interactions between humans and their biological environment. Where a disease is exclusive to humans, like smallpox, it may be possible to prevent that space from being reoccupied. However, there are always potential interactions. It is, for example, arguable that the eradication of smallpox has contributed to human population pressures on wild animal populations, and their associated organisms, provoking the emergence of new infectious diseases like SARS, MERS, Ebola or Zika. Individual examples of these viruses that are able to adapt to a human host have an advantage relative to those that are only matched to an animal host, whose numbers are declining. They reproduce and fill an empty space.
We often use the metaphor of a war to describe the human struggle against disease. This is a very unhelpful way of thinking, because it generates the sort of hubris exemplified by the Chan Zuckerberg program. Wars can, at least in theory, be won, provided that we throw enough resources into them and can exhaust the other party before we exhaust ourselves. The contest between humans and some viruses and bacteria is far more of an ebb and flow, which neither party can win in any permanent and definitive sense. This is not to say that it is not worth spending money to seek a human advantage in that contest. However, it is naïve to imagine that any such evolutionary edge can be permanent, that we can eliminate disease and, by implication, live forever. Death is also an evolutionary advantage for a species, in the opportunities that it creates for change and adaptation.
The social construction of disease is the central theme of my book, Aspects of Illness, first published in 1976 and reissued in a new and revised edition in 2001.