the science of Covid-19: global collaboration and broad-spectrum antivirals
An interesting article in the New Yorker has introduced me to David Ho, whose work on AIDS in the eighties and nineties led Time magazine to name him its person of the year in 1996. Almost forty years on from reporting the first AIDS cases in 1981, Ho continues to fight the disease, which still kills a million people a year. That might shock some people, but out of sight, out of mind, it’s not happening here. Covid-19 has killed about 100,000 in a few months, all over the world, and the global curve is no cause for complacency, to put it mildly. And you can catch it just by breathing. And many researchers have said this is just a rehearsal for the big one. Well, let’s just deal with this one first, and learn from it. People like David Ho are on the front line, desperately seeking new, comprehensive antiviral solutions.
Drug companies, however, have tended to invest in chronic viral infections, such as AIDS and hepatitis B, rather than acute ones which do deadly damage then disappear, as did SARS and MERS. Both these infections were gone before a vaccine was fully developed, so there would have been no return on investment. Many researchers are pointing out that it’s therefore not a task suited to private enterprise, which tends to be competitive rather than collaborative, as well as having other priorities. This article linked to the Johns Hopkins website focuses on some of the problems related to lack of co-ordination regarding messaging and possible treatments. The pandemic is global, it obviously disregards boundaries, so we need to be less nationalistic and proprietorial and more humanistic in response. To quote the article,
As a first step, the biomedical community needs to insist on consistent use of central registries of clinical studies and on early sharing of complete details of both successful and failed studies, and not withhold important scientific evidence as proprietary information.
If adequate testing shows promising results, that information needs to be shared immediately, in a way that can be analysed and the testing replicated. This of course includes methods of analysing and tracking the virus and its proteins. Developing treatments at the moment is tricky due to the apparently huge variation in the responses to infection – from being completely asymptomatic to the other extreme. Drugs may have to vary in toxicity to treat these varying symptoms. With effective collaboration, rigorous testing of treatments doesn’t have to be a slow process – at least it can can be much quicker than it has been before.
Meanwhile, not all health authorities are on the same page regarding physical distancing measures. The USA’s Centers for Disease Control and Prevention (CDC), a federal government agency, has sparked controversy by allowing asymptomatic ‘critical infrastructure’ workers who’ve been exposed to SARS-CoV-2 to return to work under strict guidelines. It’s noteworthy that the US federal government has been pushing a rapid return-to-work scenario for some weeks, though it has often been inconsistent in its messaging. Asymptomatic carriers of the virus are officially estimated at about 25%, though some experts argue that the figure could be as high as 50%. Individuals can also be presymptomatic rather than asymptomatic, and this is difficult to identify due to the variability of the onset of symptoms. In any case there is still the possibility of spread from either group. The lack of precise evidence about asymptomatic transmission tends to make most experts err on the side of reducing the risk. Also, according to this paper, distancing measures have likely reduced the spread of seasonal influenza (particularly virulent this season), especially in countries such as Japan, where there was an early awareness of Covid-19 prevention measures.
Not surprisingly, the advent of this virus, which has brought with it a return of all the unheeded warnings of the past decade or more, has inspired and spurred a lot of interesting new research and approaches to dealing with viruses – long regarded as the most potentially dangerous pathogens out there. The New Yorker article relates some of the history, from the first antiviral drug to be marketed in the early sixties, ‘a repurposed anti-cancer drug put to use as a topical treatment for a herpes infection that attacked the cornea’, to drugs such as ribavirin and acyclovir in the seventies, and then on to breakthroughs in the eighties in the battle against HIV/AIDS. There will be more breakthroughs with this new pandemic, but the point is that the threat of new viral outbreaks has been touted for years, but antiviral research gets limited funding and all but shuts down when there’s no clear and present danger. The current pandemic may or may not convince us that work on broad-spectrum antivirals needs to be ongoing and cannot be subject to private market fluctuations or whims.
Lest I lead people into thinking I have much of a clue as to what broad-spectrum antivirals are, let me assure you… but there’s something of a clue in the name. It should be about finding some common factor in the invasive behaviour of viruses, and what they do to replicate once inside, and using that knowledge to develop or activate agents that will shut down or act against such behaviour. A website called Creative Biolabs has a bit more to say on its front page:
By inhibiting virus replication/reproduction in infected cells or improving cellular defense system, these broad-spectrum antiviral drugs are effective in the clinical treatment of viral infection, as well as for SARS-CoV-2 infection. Mechanisms drugs with broad-spectrum SARS-CoV-2 antiviral activities mainly involve:
– Inhibiting or killing the virus directly
– Interference with virus attachment/membrane fusion
– Preventing the virus from penetrating into cells
– Inhibiting the biosynthesis of the virus
– Inhibiting the assembly and release of the virus
– Enhancing the antiviral ability of the host
From what I can gather, Creative Biolabs is a bonafide life-science company servicing various private pharmaceutical companies as well as government agencies. So hopefully I can learn, from their website and many others, more about broad-spectrum antivirals and any other possible treatments and ventures that might reduce the threat of viral epidemics.
References
https://www.newyorker.com/magazine/2020/04/13/the-quest-for-a-pandemic-pill
https://jamanetwork.com/journals/jama/fullarticle/2764657
https://en.wikipedia.org/wiki/Ribavirin
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