Envirogenetics is the combination of environment and genetics. It is the study of the ways in which factors in our external environment such as geography, diet and lifestyle influence our internal environment – our genetics, our physiology and our behaviour. The envirogenetic envelope is the particular combination of all those factors acting on an individual.

Early in the Covid pandemic, the question arose of where had the virus come from. There were many conspiracy theories, but in fact we’d seen something very similar before in terms of SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome). In both those cases, the virus had originated in animals. The former was in pangolins (also known as scaly anteaters) and the latter was in camels.

In wet markets all over China – including the Wuhan region – it was common for bats to be sold for human consumption. The bat is the only mammal that can sustain flight. So it shares a lot of mammalian systems with other mammals, including humans. But unlike most humans, the bat has to exercise regularly to find food. This provides a powerful and continuous stimulus to maintain functional muscle and mitochondria. In effect, the bat is exposed to regular hormetic stimuli, which could provide clues on how to resist the Covid virus.

When you look at the bat’s mitochondrial function and energy management alongside our own, there are considerable differences. At rest, its function in terms of ATP production is about thirty times more active than that of humans and in flight it’s about 120 times more active.

If we take into account the fact that the system for producing energy and managing mitochondria is also the one that can be recruited to deal with viruses and other infections, it seems that bats can tolerate very high levels of circulating viruses without suffering disease and without upsetting their balance of energy production, inflammation and ROS. All this means that bats are a repository for virtually every unpleasant virus you can imagine, and they have such powerful mitochondria that the Covid virus was probably like a drop in the ocean for them.

I’m sure that if people had been buying and eating bats for a number of years, the Chinese authorities would have known about it. That’s probably why a laboratory in the area where the outbreak was initially reported already had samples of the virus.

Inflammageing is accelerated ageing caused by inflammation. If the normal functioning of a mitochondrion and the other cell components it interacts with begins to be disturbed, the result is increased cellular inflammation. The more inflamed the cell becomes, the more difficult it is to sustain appropriate mitochondrial function.

It’s a vicious feedback circle that leads to other processes which mimic what happens in later life.

The microbiome is a community of micro-organisms living together. In mammals, it is located within the gut. The bacteria in the microbiome aid the digestion of food. They also contribute to regulating the immune system, protecting against disease and producing vitamins.

Quinine has a long medical history. In the 1640s, the governor’s wife in a province of Peru caught malaria and was treated by the local Indians using an extract from cinchona bark. The Jesuits in Peru saw its potential and established trade routes to distribute the bark throughout Europe.

A few years later, Oliver Cromwell died from malaria because he refused to take the same Jesuit bark.

In 1822, quinine became the first chemical medicine to be synthesised.

The Epstein–Barr Virus, one of the most common viruses in humans, is best known as the cause of glandular fever. It is also associated with diseases such as Hodgkin’s lymphoma and rheumatoid arthritis and may be a cause of multiple sclerosis. Like Covid, EBV induces chronic fatigue syndrome. It can alter mitochondrial dynamics, hamper the replication of DNA and impair our anti-virus early-warning systems.