? Absolute Vaccine Safety

Michael Ryan a spokesman from the WHO said on the BBC that it would take at least a year to develop a vaccine against COVID19 and that it was necessary, before its release, that the vaccine be shown to be “absolutely safe”.  This statement should not go unchallenged.

In a general sense, nothing is ever absolutely safe.  It is not safe to cross the road, to ride your bicycle, to drive your car, even to walk up and down stairs.  Everything carries at least some degree of risk.

Turning to medical matters, it is well known that no medicine is entirely free of risk either.  Anyone who has received a prescription medicine in a package and read the document that comes with it will see listed a whole series of risks of different frequencies which might – but do not – discourage people from taking that medicine if it has been prescribed for them.  In all cases, what is required is a balance between what is to be gained from taking the medicine and the possibility of a harmful side effect.  This is always a matter of judgement, usually by the prescribing doctor, and the idea of absolute safety is a myth and misconception.

When it comes to vaccination, there are similar problems.  One of the great triumphs of 20th-century medicine was the eradication of smallpox.  This was done by an extensive vaccination program which was compulsory in many countries. In the UK compulsory vaccination was abolished in1948 by which time smallpox in the UK was virtually eradicated. A huge eradication programme was carried out under WHO auspices in the 1960s and 70s which eradicated smallpox worldwide. Smallpox vaccination was never entirely harmless and there were deaths during the vaccination campaign.   Each was a tragedy but on balance, the number of cases of smallpox and the number of deaths prevented was hugely larger and at the time the world population at large was prepared to accept such an eradication program. 

In vaccination, therefore, one has to balance the potential gain against the possible pain.  When one is immunising healthy children against a disease they are relatively unlikely to encounter, a very high level of safety is required.  However, when one is trying to deal with a rapidly spreading worldwide pandemic, as in the case of COVID19, the situation is different.

In the first instance, it is necessary to demonstrate that any vaccine is effective in producing immunity and does not contribute to the infection through antibody-mediated enhancement.  This latter complication is known to occur naturally in the case of Dengue where second infections can produce the hugely more severe syndrome of Dengue Hemorrhagic fever.  A similar antibody-induced enhanced infection is known with other coronaviruses ([i]) and this needs to be tested for before a potential vaccine for Covid19 can be used.  This can be done both in animals and in-vitro by testing the antibodies it gives rise to on cell lines.  If a vaccine candidate can be demonstrated to be free of the risk of antibody-induced enhancement and can be shown to give rise to antibodies that neutralize the virus in-vitro, then the balance of risk and potential gain needs to be worked out largely by the modellers of the infection. They need to estimate the number of “Quality Adjusted Life Years” (QALYS) that would be saved by vaccination and the QALYS that might be lost from vaccine side effects. QALYS are used rather than lives lost to give increased weight to effects on the young rather than the old,

Both estimates will require some in-vivo human trials but these should no longer or larger than is necessary to make these estimates. They are also necessary to protect the public from “snake oil salesmen”. If the gain in QALYS is estimated to be substantially larger than the QALYS lost then it would be wrong to reject vaccination because there is no “absolute safety”.  It is the relative advantage that is important. This is the utilitarian- rather than the libertarian - view which is accepted for all the other restrictions imposed on us to control the pandemic.

One problem to public acceptance of this conclusion results from the fact that if a child (or adult) is harmed by a vaccine, his/her picture and story can be put on to TV news and into newspapers whereas those who are protected from developing a lethal or highly unpleasant disease are statistics who cannot be individually identified and do not have the same public appeal. More numerate journalism could make a real difference.

Using these criteria it should be possible to get a vaccine into widespread use in just a few months.

(Published as rapid response:    BMJ 2020;368:m1071 

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[i] For example: Jaume M, Yip MS, Cheung CY, et al. Anti-severe acute respiratory syndrome coronavirus spike antibodies trigger infection of human immune cells via a pH- and cysteine protease-independent FcγR pathway. J Virol. 2011;85(20):10582–10597. doi:10.1128/JVI.00671-11

Sensible Taxation

25 Nov 2019 

During this election campaign, all parties are making promises (or threats) concerning taxation.  All these proposals seem to accept that the current system of income taxation is to be                   maintained, whereas it is quite obvious that this system was devised for a time when calculations were done by abacus and is not appropriate for an age of calculating machines let alone sophisticated computers!

It really is quite absurd that the amount of tax one pays varies from zero per cent up to £12,500 pa and goes up to 20 per cent to £37,500 and so on and so forth.  It would clearly be hugely more sensible to relate total income to total tax payable by a formula which governments could put in place and which allow an incremental tax rate to increase to a level and at a rate of increase they think is appropriate.  This should enable the government to be able to predict much more accurately than now how much income tax they could be expected to harvest in a given tax year. 

This formula would apply to all taxable income but there would obviously be an amount of tax which is not profitable to collect and that would be deducted from the total.  This would replace the current personal allowance and be available to everybody.  This would remove one of the more bizarre features of our current tax system - the withdrawal of the personal allowance between incomes of £100,000 to £125,000 per year income which leads to a marginal tax rate of 60% which then falls again to 40% and above £150,000 to 45%.  This is really ridiculous and a more rational income tax system would also discourage some of the complicated methods of tax avoidance which costs taxpayers a lot of money and robs the treasury of much income.

Another tax which urgently needs revision is inheritance tax.  The industry of avoiding inheritance tax probably costs more money than the tax itself yields. This should surely be replaced by a more sophisticated form of capital taxation which does not depend on death.  The present avoidance mechanisms are hugely complex and fighting them costs the revenue a great deal of money.  It is difficult to know exactly how to do this but there are examples in other countries where capital gain and/or capital is taxed on a more rational basis. 

Climate Change

25 Nov 2019 

There can no longer be any doubt that climate change is real and that global warming is already now having a harmful effect on human communities in many parts of the world.  There is also a great deal of pressure to reduce CO2 output (and hopefully methane output as well) by substituting renewable energy sources for fossil fuels and reducing overall energy use. These will, if successful, slow down and possibly arrest the harmful effects of global warming.  However, there are two much more fundamental changes that are required if there is to be any real prospect of reversing global warming.  These are:

1) reduction in the global human population;

 2) increasing the efficiency of photosynthesis by widely grown plants which would enable greatly increased consumption of CO2. 

It is worth pointing out that these two changes will, on evolutionary timescales, most probably happen anyway.  It is likely that, as global warming continues unabated,  there will be epidemics and starvation and warfare on a very large scale and that the world population will indeed decrease.  Over an evolutionary timescale, hundreds of thousands or millions of years, plants will also evolve to make use of the raised CO2 levels by having an increased efficiency of photosynthesis.  However, it would be greatly in the interests of the human population that now exists that these changes should be brought about by less catastrophic means and over a hugely shorter timescale. 

A reduction of the human population

The average family size is decreasing particularly in wealthier communities and increasing standards of living is one attractive option for reducing population growth. In recent years contraceptive implants (for example Etenogestrel) have been developed that,  given subcutaneously, can prevent pregnancy for up to five years. Making these available universally and free of charge could make a substantial further impact. Unfortunately, there would be opposition to such a move from some religious groups who continue to regard humanity as an endangered species.

Increasing the efficiency of photosynthesis

The current efficiency of photosynthesis is roughly one per cent of the energy provided by the sun to plants.  I have been told at a meeting, but cannot quote the source, that the upper theoretical limit of photosynthetic efficiency is ten per cent.  George Porter, a distinguished photochemist, pointed out many years ago in his  1995 Rajiv Gandhi memorial lecture that increasing the efficiency to five per cent would allow all the energy and food needs of the planet to be met on the acreage that is currently being planted.  Undoubtedly achieving this would not be easy.  The primary enzyme concerned, rubisco, is notoriously inefficient and it has proved difficult to change it.  However, the idea - even put forward by some distinguished scientists - that evolution would have provided greater efficiency, if feasible, is incorrect.  The efficiency of photosynthesis must balance the amount of carbon dioxide available and highly efficient photosynthesis in a time of low CO2 levels would simply drive the CO2 levels even lower and cause the plants to die.  Therefore the need for this highly efficient photosynthetic plant is only temporary and once the CO2 levels have been brought down again it would need to revert to the previous less efficient photosynthetic mechanism. 

There should be a real Manhattan project-scale effort put into the project of raising the efficiency of photosynthesis as this would on its own rapidly solve the climate problem.  It is therefore particularly depressing that the Green movement still continues campaign against the genetic modification of plants for reasons that are difficult to fathom.  One hopes that wider counsels and more common sense can be brought to bear. 

Update on Brexit

Now that we have a government preparing for a no deal Brexit it is perhaps appropriate to make some predictions of how this will affect United Kingdom.

It would seem almost certain that Scotland would decide to become independent of England and to remain in the European Union - with or without the approval of the Westminster Parliament. This would leave a hard border between England and Scotland for which absolutely no provision is being considered.

It is almost as likely that the Northern Irish would also leave the United Kingdom. They would have the option of joining the Irish Republic to form a united Ireland or to form a new union with the Scots. I would hesitate to predict which they would choose.

The Welsh would probably also wish to stay within the EU and decide either for independence on their own or perhaps also form a union of the Scots

This would leave England isolated and almost certainly severely economically and politically damaged. I would guess that within a few years they would apply to re-join the European Union - but that would not recreate the United Kingdom.

Is this what was voted for in the 2016 referendum?  I think not.

22 Jul 2019

The assisted dying debate

Some days ago I listened to the House of Commons debate on assisted dying. Powerful arguments in favour were put forward, many for patients with motor neurone disease who were not necessarily predicted to be within six months of death.

The arguments against depended almost solely on the contention that because assisted dying might be abused to pressurise dependent old people into suicide that therefore all assisted dying should be prohibited. 

This is not a compelling or even an acceptable argument.  There is almost no human activity that cannot be misused and the answer cannot be to prohibit all such activities.  For example, driving a car can be abused by speeding or driving when intoxicated or causing accidents by lack of attention, but nobody in the past has suggested that driving a car should be forbidden because of these abuses.  Social media on the internet appear to be famously subject to misuse of a whole variety of kinds some of which endanger the mental health of people who make use of them and yet there has been no major campaign to forbid the use of the internet.  To take the argument to its extreme, you might say that one should prohibit all sexual intercourse because of its abuse by rape.  In that case, presumably the human race would either die out or would have to be repopulated along the lines laid out in Brave New World by artificial techniques.  It is really hard to believe that even the most “pro-life” members of the House of Commons would really support such actions.

It is only where there is compelling evidence that it is really impossible to put in place regulation that prevents major and significantly common abuse that the prohibition argument can be allowed any validity at all.  This is certainly not the case with regard to assisted dying.  Where assisted dying is allowed – Holland, Belgium and Oregon being good examples –  no evidence is forthcoming that there has been any serious problem with such abuse.  In these circumstances this argument against assisted suicide should be abandoned.

The Brexit Referendum

This letter was sent to the Times but was neither published nor acknowledged

Conduit Tail, 38 Conduit Head Road, Cambridge, CB3 0EY

Professor Sir Peter Lachmann FRS FMedSci

15 September 2017

The Editor
The Times


Dear Sir

In writing in this morning's Times about "MPs ignoring the voters clear instruction to leave the EU" Philip Collins  greatly over interprets the result of the referendum.
At the same time as the Cameron Government put through the European Referendum bill that treated this major constitutional change as if it were a constituency election for an MP, they also passed the Trade Union Act of 2016 that stipulates that for a strike in important public services there needs to 40% of support of all those eligible to vote. This should surely have also been taken as the minimal requirement for a clear instruction on an issue as important as leaving the EU.
It was not achieved. Giving the results in percentages of the electorate of 46.5 million, the leavers received 37.44% ; the remainers 34.71%;  and 27.85% did not vote or had their ballots rejected. This left the leavers 2.56% of the electorate - some 1.19 million voters - short of what would have been necessary to call a strike in health, education, transport, border security or fire sectors.
With a mandate as marginal as this, there is every reason to support the efforts of those who would require any final Brexit deal to be approved by Parliament or by a further referendum that requires the votes of, at least, 40% of the electorate.

Yours Sincerely

Peter Lachmann

The Olympics and selective schooling

 

With justification, the whole country is enthusiastic about Team GB’s success in the Olympics and the Paralympics.  This success has been achieved through a policy of selecting the most talented young athletes and allowing them full-time training in the company of their peers and with the best available coaches.  No-one seems to worry that this process may be unfair to the somewhat less talented athletes who are not recruited into this process and who may be made to feel rejected as a result. 

This contrasts starkly with the arguments rejecting selective schooling, one important aim of which should be selecting the most academically gifted children and educating them as a group with the best possible teachers as a way of creating an intellectual elite capable of a comparable performance in the “Intellectual Olympics” if there were such a thing. 

There is really only one conclusion that can be drawn from this contrast - that the country does not esteem intellectual success at the highest level in anything like the way it regards success in the Olympics or indeed in football.  This is a pity since the cultural and even economic success of the country really depends on producing a cadre of those who by endowment, education and training, are able to produce success comparable to that of Team GB at the Olympic Games.

This argument should not be taken to imply an uncritical attitude to all forms of academic selection.  In particular, it is clearly unwise to do this selection at one single point in time, at the age of 11.  There should always be the opportunity for those who develop later to join the elite training programs; and those who fail to do well at the highest levels may be more comfortable in returning to a less challenging training environment.

Nor does the argument favour “between-school” selection over “within-school” selection. But it does imply that schooling is primarily about promoting educational excellence and only secondarily about other, also highly desirable, ends such as promoting social equality; and that it should aim to achieve both.