Long-term Vaccine Safety: the Facts

Still commonly shared online, the claim that we don't know the long-term side effects of  Covid vaccines is untrue. In fact in the scientific and medical world, a year is considered 'long-term' when it comes to vaccine safety.

It is now (25th Feb. 2022) more than 14 months since the first Covid-19 vaccine dose was given, and a year since the first delivery of Covid-19 vaccines under the Covax scheme. Scientists explain that this is more than enough time for all but the rarest side effects to have emerged. 

In fact the number of people who have received vaccine is more important than the length of time vaccines have been in use. New vaccines undergo stringent procedures to identify (a) whether it works, (b) if there are any side effects and (c) are the side effects mild or severe. In normal times, vaccine trials have gaps between the different stages due to researchers obtaining funding for the next stage. With Covid-19, funding was made instantly available, thus shortening the time from concept to production.

What happens in your body?

Covid vaccines may be new, but the processes they trigger in your body are not, and we know how the immune system works. Understanding how they stimulate the immune system can help us understand how quickly we can expect to have any negative reactions. 

After 15 minutes

• A tiny fraction of people will have an allergic reaction to the inactive ingredients in the vaccine and this will happen within about 15 minutes of receiving it.

After a few hours

• Shortly after receiving the vaccine, the immune system recognises an alien invader and attacks it with immune cells, the weapons it would use against any virus or bacteria.
• In this innate phase, any reactions will happen within hours or a couple of days, including the most common side effects of a sore arm, temperature and other flu-like symptoms.
• Also in this phase is a much rarer side effect which has been linked to the mRNA vaccines Moderna and Pfizer is myocarditis (inflammation of the heart).
• While the exact cause of myocarditis is not understood, inflammation is one of the body's responses to infection or injury.
• Vaccine induced mycarditis is generally mild, and gets better on its own or with basic anti-inflammatory drugs such as ibuprofen.

After 10 days

• The innate phase also starts the second phase of your immune response - the adaptive phase - where your body starts to make cells which are specifically tailored to fight off the target virus. 
• As this phase starts around 10 days after infection, which is why vaccines will take this length of time to begin to have an effect in protecting you against Covid. 
• Your body pumps out new immune cells, peaking after about two weeks and fading away after about 28 days. 
• A very rare but serious side effect linked to the Astra-Zeneca vaccine (a specific type of blood clot) happens during this phase and is related to the antibodies produced by your immune system in response to the vaccine. That is why most of these rare clots have been seen within four weeks of vaccination.

By 28 days

• Once the adaptive phase dies down - after about a month - you are left with memory cells which give you protection for months or years after initial exposure but don't generate new responses. If you have not a reaction after the first couple of months, it is incredibly unlikely that anything that happens after that will be caused by the vaccine.
• While there is never a 100% guarantee with anything in medicine, vaccination history shows that most side effects occur within hours of receiving the vaccine, and rare side effects within days or weeks.  

Will we identify new side effects?

• From our hundreds of years of knowledge showing how the immune system works, an individual who has not had a reaction to a vaccine in the first couple of months, is vanishingly unlikely to have any new side effects after that.
• Countries world wide have put systems in place to monitor side effects and to share that information with each other. 
• It is these systems that picked up both the blood clots and myocarditis, which are extremely rare with only a handful of cases per million doses.
• While milder symptoms (e.g. sore arm or temperature) are likely to be under-reported, the more severe side effects are thoroughly recorded.
• Billions of doses have already been given, so any side effect not yet seen would be rarer than one in a billion.
• While the vaccines have all completed the expected three phases of trials that usually take place before being offered to the general public, they are still being carefully monitored until at least 2023, to make sure even the rarest of events are identified.

And remember....
All the evidence suggests that the overall risks of catching Covid far outweigh any risks from the vaccine.

Source: Covid: How we already understand long-term vaccine safety by Rachel Schraer (BBC Health and misinformation reporter)

The Origins of the Anglo-Saxons

The origins of the Anglo-Saxons by Jean Manco (Thames & Hudson Ltd, 2019)

This is a very detailed and fascinating book, which includes the following information.

• Population
• In 1066 England was conquered by the Normans, who replaced the English aristocracy. In the medieval period there was immigration into England from continental Europe, as well as from Scotland, Wales and Ireland.
• The DNA of the modern English population cannot be modeled as a simple mixture of Anglo-Saxon and Celtic. Migration from 1066 onwards has left its mark.
• Language
• Old English, the language of the Anglo-Saxons, developed into Middle English (1100-1500), followed by Early Modern English (1500-1800) and Modern English.
• Although Modern English is a Germanic language, 70% of its vocabulary is non-Germanic, borrowed from many other languages, notably Latin and French. This polyglot vocabulary makes English the richest language in the world.
• English today is a global lingua franca, partly as a legacy of the British Empire, but mainly due to the super-power status of the US.
• History
• In the Middle Ages, a pseudo-history of Britain was far more popular than the genuine article.
• Interest in the Anglo-Saxons began to revive in the Tudor period and greatly increased in the Victorian period.
• The surge of national pride in the 19th century encouraged racism and an inflated concept of the Anglo-Saxon achievement, which produced a backlash after the Second World War.
• JRR Tolkein was a scholar of the Anglo-Saxon language, who changed the scholarly view of Beowulf but left a greater legacy in his popular fiction (The Hobbit and Lord of the Rings), which have now been produced as films.
• Who were the Anglo-Saxons?
• Archaeology can reveal those details of contemporary life in Anglo-Saxon times that documentary sources omit.
• The Romano-British population was overwhelmingly Celtic but included individuals from many parts of the Roman Empire, including some Germani (this is the correct spelling) within the Roman army.
• The Anglo-Saxon ingress was almost the opposite of the Roman conquest.
• Ancient DNA indicates that the Anglo-Saxons were incomers.
• There was no reason for the Roman British population on the whole to imitate the Germanic way of life, but individuals could adopt it by marriage or other assimilation.

END

Should We Reform the UK School External Exam System?

 The external school exam system in the UK has been unchanged for some years. In school year 11, students usually sit their GCSE exams. [These were previously known as O (Ordinary) Levels] In year 13 (Upper Sixth form) students sit A Levels (Advanced). Both are set by a number of national exam boards.The exams consist of written papers, with some subjects requiring one or more elements of course work, practical work and oral examinations for languages. The marking is done by external examiners and moderated. Marks are allocated to a range of grades. Based on mock (practice) exams, teachers typically give students a predicted grade, but this is only an indication of their likely actual grade.

No exams took place in summer 2020 due to the coronavirus (Covid-19) outbreak. To enabled students to receive qualifications, it was announced  that students who were due to sit A level, AS level or GCSE exams this summer would receive a calculated grade. For each student, schools and colleges provided a centre assessment grade for each subject; this is the grade their school or college believed they would be most likely to have achieved had external exams gone ahead, taking into account a range of evidence including, for example, non-exam assessment and mock exam results. This grade was intended to be put through a process of standardisation, using a model developed with Ofqual, to arrive at the final calculated grade.

However the moderation process was flawed and downgraded (sometimes heavily) the marks for many students. The biggest effect was on A level students, many of whom were unable to take up university places, and these were allocated to other students. On Monday 17th August, Ofqual confirmed that there would no longer be a standardisation process for A level, AS level or GCSE exams and instead all students would be awarded the centre assessment grade submitted by their school or college, unless it was lower than their calculated grade, in which case the calculated grade would stand. Unless there was evidence that a processing error had been made, these grades would be final. This U-turn meant that students who had been refused a university place on the basis of the flawed grades, now had no places and universities had to try and sort out the mess.

Tom Brighouse has written about the system of examinations in the UK, indicating that he feels our children are possibly the most tested. He notes that in other countries the system is less stratified, and the English system is unusual in having decisive exams at age 18.

TB has suggested that we need to move to a broader qualification at 18, which is part exam, part record of achievement and part long-term project. Some students might excel in one type of assessment (e.g. open-ended essay, multiple choice questions or oral examination) and do less well at others. Universities use the same methods but add in observation of work by staff, collaborative work and vivas (where the student is questioned individually in an interview).

TB further notes that (a) teachers are not taught how to assess, and want their students to do well, (b) teachers are not immune to unconscious bias and (c) exams are a single day snapshot. Companies who want problem solvers, collaborators and good communicators, are therefore devising their own skills based assessments as part of their recruitment process.

Digitisation may offer ways to track progress, using results over time from different 'tests'. The bigger the variety of assessment methods, the more chance it will be fair.

END

Alzheimer Dementia Causes and Treatments

 Alzheimer's is typically thought of a disease that affects the elderly, but ten per cent of people with Alzheimer's have the early-onset form and are under the age of sixty-five. While about 50% of early-onset Alzheimer's cases do not show specific mutations, there is a strong genetic linkage. Mutation positive for genes APP, PS1 or PS2 is a solid confirmation of the diagnosis. It is possible that those without these mutated genes may have other mutated genes that also cause the disease. Sadly, the genetic element means that any offspring may have inherited the mutated form of a gene. This can only be diagnosed by genetic screening.

2012: Current drugs for treating Alzheimer's dementia can slow its progression for a significant period of time but are not a cure. The sooner someone is diagnosed and put on medication the more likely they will be able to benefit if better treatments become available. Examples are Aricept (boosts cholinergic functioning) and Namenda.

Diagnosis: finding amyloid plaques and/or neurofibrillary tangles in the brain.

The cognitive deficits - the symptoms of dementia - occur before the plaques form and neurons die. 

In the brain of someone with Alzheimer's, there is too much of a soluble protein called amyloid-beta 42. Either too much is made or not enough is cleared away. When too much is present, these individual little peptides stick together and form small oligomers. These gluey oligomers of amyloid-beta 42 lodge in synapses - the spaces between neurons - and interfere with synaptic transmission, the ability of neuron number one to 'talk' to neuron number two. And when this happens, new information isn't learned. Or old information can't be accessed. Synaptic plasticity suffers. Over time because this synapse isn't working properly and because of inflammation and other problems, that nerve axon terminal will retract. Eventually, unable to function, the neuron will die, leaving behind empty space (the atrophy seen on MRI scans) and possibly a heap of amyloid-beta 42 in an amyloid plaque.

The degree of dementia correlates only with  synapse dysfunction, not with neuronal loss, not with number of plaques, not with atrophy on an MRI scan.

The cure (disease altering) treatments will need to:

• impede production of amyloid-beta 42,
• increase clearance of already produced amyloid-beta 42,
• prevent amyloid-beta 42 from sticking to itself so it can't form oligomers, or
• rip these already formed oligomers apart.

If such treatments are found, the hope is that people suffering from symptoms of dementia can be treated before they've experienced any neuron death. If the synapses are fixed, neurotransmission can work again.

Source: Still Alice by Lisa Genova (Simon & Schuster, 20012)

Cataracts

What are cataracts?

Cataracts are cloudy patches on the lens in the eye, which cause blurred vision and eventual blindness if left untreated. It is estimated that in the UK one in three people aged 65 has a cataract in one or both eyes.

Most develop due to age-related changes in the lens

• An imbalance between free radicals (unstable atoms that damage cells) and antioxidants (which keep free radicals in check). Cells in the body produce both, but smoking, drinking too much alcohol and exposure to chemicals can speed up production of the damaging free radicals.
• As we age, fewer antioxidants are produced, resulting in oxidative stress, leading to tissue damage; proteins and fibres in the lens start to break down and calcium builds up in the lens.
• Cataracts are also linked to conditions such as diabetes and to medications, includinglong-term use of steroids.

Current treatment

The current treatment is to replace the cloudy lens in a 30-minute operation under local anaesthetic. The cloudy lens is removed through a small cut in the eye, and replaced with a plastic one. About 350,000 cataract operations are performed in the UK each year.

New treatment developed

Scientists at US-based Nacuity Pharmaceuticals have developed a 'pellet' implant (NPI-002) that is injected into the eye to prevent cataracts forming, and might even reverse the growth of existing cataracts without surgery. This is now being tested in the first clinical trial.

• The implant is thought to work by lowering calcium levels in the eye.
• The implant is loaded with antioxidants and injected into the vitreous, the gel-like fluid between the lens and the retina (the light-sensitive area in the eye). The solution includes N-acetylcysteine amide (NACA), an effective antioxidant.
• The implant slowly releases its contents into the vitreous, which carries them to the lens where it acts on the cataract. 

First clinical trial

An animal study by ophthalmologists at Washington University, US, and other centres, reported in the journal BMC Ophthalmology in 2018, showed that the implant prevented and reduced the severity of cataracts. It also led to an increase in protective antioxidants, and reduced calcium levels to 2.5 times lower than a control group.

The first human trial, in the US, will start soon (late 2021) and will involve 30 patients aged 65 and over with cataracts.

Initial interest in the implant is tempered with caution. Gwyn Williams, a consultant ophthalmologist at Singleton Hospital in Swansea, said "It is a very interesting idea and I look forward to seeing the results. Cataracts are multi-factorial and I am sceptical that this one approach will be effective by itself, though this remains to be seen."

Source: Scientists develop 'pellet' that can be injected into patient's eye to prevent cataracts forming - and could even reverse existing traces. Daily Mail (5 Oct. 2021)