1. I've had a surprising number of conversations about Covid-19 over the past week or so, all sparked by the fact that I was, as always, wearing an FFP2 respirator. People in healthcare facilities, taxi drivers, people on trains and buses. 2. All of these conversations were perfectly pleasant. The theme that ran through all of them was a genuine belief that Covid-19 was 'gone'. Not endemic, or 'just a cold', but 'gone'. When you see videos on social media featuring young people bemoaning their 'mystery illness'...

1. The intense and all-encompassing institutional and societal pushback seen in some countries against any intervention to mitigate the impacts of Covid-19, whether that be vaccines, or air filtration / purification, or masks, is not simply as a result of mandates or lockdowns. 2. The memory of these policies is a component of it, to be sure, but the deep underlying reason is a shared yearning for the world to be as it was in 2019. In effect, 2019 has become the status quo that almost everyone needs to cling to. This need is pathological in nature.

1. I was at my local pharmacy this morning to pick up a prescription, and as I walked up to the counter, I immediately noticed that the elderly woman in front of me in the queue was wearing a blue surgical mask. She was adjusting it, pulling it up over her nose. 2. She was also quite obviously unwell, and frail in a manner very similar to the frailty my late mother first developed around 2017. As the pharmacist spoke to her, she adjusted her mask again, making sure it fully covered her nose and mouth.

1. Biological risk is both multifaceted and additive. Any of the following individual risks would be concerning; when combined, they effectively constitute a powder keg waiting for a spark: 2. The growth of antivaxx ideology globally (and its institutionalisation in policy).

The retreat of many national public health services due to political and public blowback from the response to Covid-19.

Climate change increasing the spread of many vector-borne pathogens.

1. 'Overall, our findings raise compelling questions about the potential role of SARS-CoV-2 infection in accelerating or triggering neurodegenerative diseases linked to protein amyloidosis'.

An example of such a disease is Parkinson's Disease (PD).

pubs.acs.org/doi/10.1021/ac… 2. As the article notes, a form of PD was a noted sequela of the Spanish Flu (many people who developed encephalitis lethargica went on to develop it).

Anosmia is a common prodomal symptom of PD.

1. As a consultant analyst that generally presents to the C-suite of organisations, I am often asked to produce short, concise explanations of both biological and geopolitical risks. Regarding Covid-19, I use the same summary with both C-level clients and friends: 2. SARS-CoV-2 is a pathogen that can cause both acute and chronic disease. Vaccination reduces the severity of acute disease and the risk of developing chronic disease. However, current vaccines are insufficient to meaningfully reduce ongoing infection and transmission.

1. I've said exactly this for quite some time. Expanding on Adrian's point here, Covid-19 has three distinct characteristics as a disease that enables it to be denied at a societal level.

https://twitter.com/SillyPutty78/status/1954315595039887370

2. First, none of its symptoms trigger the human disgust mechanism. Adrian gives a great example of this. The two key symptoms that distinguish Covid-19 from other common diseases are cognitive dysfunction and anosmia, both of which are *invisible* to other people.

1. A recent conversation with a colleague threw into sharp relief exactly why I am so inspired to develop technologies to prevent pathogenic infection. So, if you'll indulge me, let me explain. In early 2002, I had what to all intents and purposes was a cold. Sniffles, cough etc. 2. I just took paracetamol and got on with it, and was completely fine in a few days. About a week later, I suddenly developed widespread and extensive muscle twitching - fasciculations. These fasciculations got severe really quickly, enough to cause chronic insomnia.

1. The most important concept in this excellent article is this:

'the team wanted to explore what he called a “*reciprocal relationship*” between COVID-19 and chronic conditions'.

* my emphasis
oregonlive.com/health/2025/07… 2. “If you had already had metabolic disease, like obesity, diabetes or hypertension, that meant that if you got COVID, it was going to be worse,” he explained. “On the other hand, there was a potential risk of new-onset metabolic disease after COVID.”

1. Allow me to clarify, beginning with a definition: by 'rigorous indoor masking' I mean 'wearing a mask in all indoor public spaces'. This, of course, means no eating, although hydration is possible using a sip valve.

https://twitter.com/PeteUK7/status/1944594295396176350

2. Why do I write that it can be really difficult? Because acknowledging the sacrifices that people have made as a result of rigorous masking - some for over five years now - to protect both themselves and others is very important.

1. Outstanding summary of a recently published study on cognitive dysfunction in Long Covid (link to study at end of thread). The important point here is the 20% prevalence of anosognosia: having cognitive dysfunction but not being aware of it.

https://twitter.com/ZdenekVrozina/status/1944055754778153150

2. This was also a finding of the SARS-CoV-2 Human Challenge Study.

From the Discussion: 'This apparent discrepancy between objective and subjective measures could be interpreted as indicating that the tasks are sensitive enough to detect small...
share.google/sh8p64mCjstfgX…

1. The prevailing discourse surrounding mitigating against SARS-CoV-2 infection is rife with false dichotomies. At a societal level, the most obvious of these is the notion that mitigation measures stand in opposition to economic growth, when, in fact, the opposite is true: 2. Mitigation measures - specifically widespread air filtration or purification - would increase economic growth, by virtue of reducing ill health in the workforce (implementing widespread passive mitigations would also increase operational resilience to future pandemics).

1. There have been some exceptional comments on this thread, and as a result I'm going to recount a personal experience from 2020 that explains why I come down much harder on the side of incompetence rather than conspiracy.

https://twitter.com/brownecfm/status/1936358347139092562

2. When the UK 'Eat Out to Help Out' scheme was launched in 2020, I told every single person I knew not to take advantage of it. It's important to remember two points here: that this was before the availability of vaccines and that everyone I told knew and trusted my expertise.

1. With a new wave of Covid-19 incoming, and remembering my recent comments on the sustainability of risk mitigation, my current protocols are:

Vaccination every six months.

Masking in all shared indoor public spaces.

No masking outside. 2. NAAT testing for all guests (I use PlusLife). If NAAT testing is negative and no-one has symptoms, masks are removed.

I have a small group of friends who take the same precautions as I do; for this group, NAAT testing is not required. I trust them and they trust me.

1. This adds weight to a point I've been making for years, namely, that the important differential at the population level between now and the Spanish Flu of 1918-1920 is the considerably higher percentage of the global population who are immunocompromised.

https://twitter.com/HarrySpoelstra/status/1915153362703524007

2. People who were immunocompromised as a result of primary immunodeficiencies didn't live long in 1918, because antibiotic therapy didn't exist. Likewise, medication that causes immunosuppression didn't exist either.

1. Perhaps the most damaging blowback from the response to Covid-19 in 2020 and 2021 is the mainstreaming of a public health ideology that is rooted in a dangerous combination of survivorship bias, nostalgia, and the naturalistic fallacy. 2. As a disease, Covid-19 elicits this widespread reaction because of what I refer to as its 'stretchiness' - the fact that it can cause disease on such a broad spectrum of severity, from asymptomatic infection to death and everything in between.

1. To understand the navigation of an environment in which multiple and competing risks exist, a thought experiment - grounded in my own life - is useful. I am a recovered alcoholic, and my sobriety is the single most important element of my life. 2. If a genie was to appear before me and offer me lifelong and complete immunity to SARS-CoV-2 infection if I drank a single alcoholic drink, I would immediately refuse; the risk of jeopardising my sobriety vastly outweighs the risk of Covid-19.

1. Masks are tools used to mitigate the risk of infection by airborne pathogens, including, of course, SARS-CoV-2. The politicisation and the consequent symbolisation of masking has, overall, reduced their use. This is true whether you are anti or pro masking. 2. Increasing the symbolisation of masking is a guaranteed way to reduce their use even further. This is why I am adamant that my use of masks is purely for risk reduction. I make no statement by masking; I simply have no desire to get infected.

1. As I have mentioned several times before, the moment I learned that anosmia was a cardinal symptom of Covid-19 was the moment I decided I was going to do everything in my power to not get infected with SARS-CoV-2.

nature.com/articles/s4159… 2. I knew anosmia was a prodomal symptom for both Alzheimer's Disease (AD) and Parkinson's Disease (PD). I also knew that encephalitis lethargica - which in some cases developed into a form of PD - was the major sequela of the Spanish Flu.

1. From the linked article:

The pandemic has been blamed for a decline in school readiness among reception-aged children, but some teachers who took part in the annual poll *said the “Covid baby” explanation was starting to feel like an excuse*.
theguardian.com/education/2025… 2. From this recent article in Nature:

'In summary, children exposed to antenatal COVID-19 have higher frequencies of DD as compared to non-exposed controls. Risk factors for DD beyond maternal COVID-19 were not identified across sites; ...
nature.com/articles/s4159…

1. As I noted recently, science is inextricably nested within politics. Public health, epidemiology, virology and so on, all subject to the whims of politics. We are seeing this very clearly now. However, viruses are not nested within politics.

Viruses are molecular sharks. 2. We must be careful not to anthropomorphise viruses; they sit on the very edge of what we define as 'life'. However, the function of a virus is simple: replicate. To produce more viruses by hijacking animal or human cells.