Issue #62: The COVID-19 story is terrific but don’t assume R&D can solve every problem

Written by Nobel Laureate Professor Peter Doherty

One of the issues that concerns me about the immense power of contemporary molecular science is that the extraordinary capacity we’ve seen come to the fore during the COVID-19 pandemic sends out a subliminal message to the broader public that there’s a technological fix to every serious threat that confronts us. But all professional researchers and technologists understand that, while breakthrough discoveries like those that are recognised by Nobel Prizes can change the dynamics fast, we can have no certainty that this will happen to provide a timely solution for some intractable issue. And just throwing money at a problem doesn’t necessarily work, as the immediate response is to try to find a solution in currently available technology, a strategy summarised in the past as ‘funding canon builders to put a man on the moon.’ What can happen is that resources are withdrawn from the type of discovery science that might, often from ‘left field’, come up with a viable solution.

Of course, the expectation that there’s a scientific fix for everything is not limited to medicine, but is also true for the whole spectrum of research and development (R&D). A primary example of just how dangerous the idea that science and technology (S&T) can quickly solve all major problems comes from climate science. Though innovative physicists, chemists, engineers and even biologists are indeed developing technologies (better batteries, electric cars) that make major contributions to cleaning up the energy generation and use equation, every serious person I know in those areas is absolutely convinced that we must change behaviour and drastically reduce greenhouse gas emissions now. The ultimate fix for stationary energy generation is nuclear fusion: in effect, to recreate the power of the sun on earth. But, despite spending hundreds of millions of dollars, that’s been ‘20 years off’ for as long as I can remember. We can’t mandate breakthroughs!

Like COVID-19, climate change is a health problem. Think of the terrible bushfires across Australia that overlapped with the start of this pandemic and reflect also on the multifaceted health and wellbeing issues that resulted for both humans and other species. Apart from acute fire and heat-related deaths (which can be remote from the fire grounds), a spectrum of psychological and medical, including respiratory, problems have come to the fore. Then there are also issues like the impact on food and timber production, including the ‘hard baking’ of the earth, the pollution of rivers and dams with ash and, of course, the massive damage to biodiversity.

A different example of the limitations of S&T comes from considering how molecular medicine strategies that allow one problem in infectious disease to be solved, but do not work for another is HIV/AIDS. Looking at the SARS-CoV-2 virus from the time it was first isolated, immunologists like me had some concerns that there may be hidden issues that could be problematic, like the development of ‘enhancing antibodies’ (#20), but were otherwise confident that protective vaccines could be made. As it transpired, the level of success, especially with the new mRNA vaccines, went way beyond our best expectations (#49).

Apart from writing this Setting it Straight series, I’ve been heavily involved in public communications from the early days of the pandemic, often in ‘talk back’ or Q&A formats that, in this rapidly changing story, have proven to be much more effective than delivering formal lectures. One of the issues that’s been raised is: why, if it’s so easy to make a COVID-19 vaccine, do we not have vaccines to protect us against HIV/AIDS? Sometimes there’s a tinge of anger, with the questioner speculating that, because AIDS is a sexually transmitted infection, or a problem for injecting drug users, there has been some reluctance to drive such R&D using public tax dollars.

But nothing could be farther from the truth. Immense amounts of money, and some of the best minds in molecular and clinical science, including Sharon Lewin, Damian Purcell and Steven Kent from the Doherty Institute, have dedicated substantial effort to the AIDS vaccine enterprise. That’s also true of the USA’S National Institute of Allergy and Infectious Diseases Director Tony Fauci and, while my personal involvement was limited because I was working mainly on influenza immunity, the fact that I wasn’t funded for AIDS research led to my being involved in chairing, or being a member of, scientific advisory for multi-million dollar operations (especially in the USA) directed at making an effective AIDS vaccine.

The problem is not insufficient funding, it’s the virus! Retroviruses like HIV are not ‘retro’ because they are old fashioned, but because they carry an enzyme called reverse transcriptase that retro-copies the HIV genome back into our genome. As a consequence, these are persistent infections that, unlike the coronaviruses and influenza viruses, aren’t eliminated by normal immune mechanisms. While an HIV-infected individual’s immune response can hold the virus in check for a time, HIV has – like the influenza viruses and unlike SARS-CoV-2 – no proof-reading mechanism. The result is HIV immune-escape mutants that emerge constantly within an infected person and do an ‘end-run’ around immune control. And, as these mutant strains can infect others, vaccines against the parent virus no longer work. Next week we’ll continue with this discussion of immune escape, mutant selection and vaccination, both for HIV and for SARS-CoV-2.