The Doctor’s Surgery

I’m optimistic – not exuberant – about chances of a COVID miracle

Hope springs eternal in the Dow Jones index. It is not surprising that it rose very sharply on the announcement of an effective vaccine against COVID-19 – effective, that is, in raising the share price of its manufacturers.

Whether it will prove effective in the more important public-health sense of the word is not yet clear; there are too many unanswered questions (as of this very moment) for us to be able to say. Perhaps this is the beginning of the end of the war against COVID, but perhaps not.

The first thing to note about the trial is that it was almost certainly conducted on people who were at very low risk of serious illness in the first place. There was a reduction in the number of cases by 76 in about 21,750 people who were given the vaccine.

The case fatality rate from the disease in this group was probably far less than one per cent. So it is likely that not a single life was saved by giving 21,750 doses of vaccine.

It is as yet unknown how long the immunity conferred lasts: only time will tell. A follow-up period of 28 days is not long, to put it mildly.

It remains unknown whether the results will be reproducible in other age groups. One cannot merely transpose results from one group to another. It is not yet known whether the vaccine will reduce transmission of the disease as well as the risk of contracting it.

No safety concerns arose during the trial. Still, it was too small to detect rare but serious side-effects that occur in fewer than one in 7,000 cases.

The Oxford vaccine, as far as we can tell, had advantages over the Pfizer and Moderna vaccines. It is much cheaper and is far easier to store. It seems somewhat less effective, though a proper dosage regime might reduce the difference. It would not be surprising if nationalism played some part in what vaccine a country chooses to use.

News of vaccines has lifted spirits. If their promise is fulfilled, how long will it be before collective amnesia as to what we have been through sets in?

The vaccine might indeed be the equivalent of the polio vaccine, which has almost eradicated that disease from the world; but, as yet, it is far from certain.

The results are encouraging but only preliminary. For people aged 40 and younger, approximately 250,000 doses of the vaccine would have to be given to healthy individuals to save a single life.

If there were a life-threatening complication in every 50,000 doses, there would be five times as many such complications as lives saved.

The odds are much better for the elderly – provided the efficacy and safety are the same for them as for younger people. The number of immunisations needed to save one life would be at least 1,000 times lower for those aged over 90.

If the most vulnerable people could be protected, the need for such measures as social distancing and lockdowns would be reduced, if not eliminated.

A vaccine that has to be stored at –70°C and given twice at an interval of two weeks poses the kind of logistical problems our incompetent government does not seem to excel at solving.

There are grounds for optimism, then, but not for what Mr Greenspan called irrational exuberance.

This vaccine is bound to provoke a conspiracy theory: that the authorities, in league with the pharmaceutical companies, seek to poison the population for political or financial ends.

To achieve these ends, they will suppress evidence of the harmful effects of the vaccine, and no argument to the contrary will ever satisfy those who hold to the conspiracy theory.

One can only hope that there is herd immunity to such theories.