Yes – of course this is a Covid-19 post. 

However, I’m not going to simply highlight the over-rich daily diet of mortality rates and pictures of people spectacularly breaking lockdown rules. 

This time, its why falling virus numbers could be bad news after all…

Professor Adrian Hill leads the Oxford team who were one of the front runners in the race to develop a successful vaccine. His team’s vaccine, ChAdOx1 nCoV-19, looks extremely promising. Prof Hill said a few month’s back that he felt there was an 80% chance it could form the basis of an effective vaccine by September.

So why is he now saying that there is only a 50% chance of having any result at all?

The reason is that it’s becoming increasingly hard to recruit the 10,000 adults and children the study needs.  As he told the Daily Telegraph –

“it’s not a race against the other guys. It’s a race against the virus disappearing, and against time.”

Hill’s team is working with AstraZeneca to develop the vaccine, and the UK government has already signed up for up to 100 million doses.

Just last month, AstraZeneca were hoping for answers on vaccine efficacy in June or July. It now seems the process could take far longer, unless transmission rates stay high.

Falling transmission rates may seem like a good thing, but those who fall into the category of extremely vulnerable, really need a viable alternative to solitary confinement.

One way out of the mire is to intentionally infect healthy volunteers with a weakened version of Covid-19. These so-called “human challenge studies” (HCS) are somewhat controversial – especially as some of the participants would, by design, receive a placebo followed by the virus.

This does seem to be somewhat stretching the 3rd principle of GCP – that the rights, safety and wellbeing of the trial subject is more important than the interests of science or society.

In April, the US FDA was sent a letter from 35 US Representatives urging it to take nothing off the table in searching for a Covid-19 treatment – including HCS. They see no inherent ethical problem in HCS, believing the benefits outweigh the risks.

The US vaccine expert, Stanley Plotkin, and New York University bioethicist, Arthur Caplan, argue for HCS in upcoming article for the journal, Vaccine. They argue that if the normal process is followed it –

“…normally takes months to years, during which SARS-2 will infect and possibly kill millions.”

They see human challenge trials as a way of speeding things up.

So the next time you hear the news that infection rates are falling, just pause before celebrating too loudly.


Ashley Smith

Ashley Smith

Ashley devotes most of his time to Whitehall Training. As one of the longest standing members of the team he has overseen the development of our courses, ensuring they stay up-to-date and accurate. In his free time Ashley likes to listen to music, especially his favourite group: Orbital.