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The burning building

BMJ 2020; 368 doi: (Published 19 March 2020) Cite this as: BMJ 2020;368:m1101

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Extraordinary times: is yoghurt the extraordinary solution? Re: The burning building

Dear Editor,

There are trillions of bacteria growing on our body surface and billions growing within our tissues. The latter include bacterial pathogens which induce inflammation and cause disease [1, 2]. Viral respiratory tract infections also cause inflammation. Furthermore viral respiratory tract infections can lead to secondary bacterial growth in the oropharynx thereby increasing inflammation. All these processes are in play in the current Covid-19 pandemic. There are three main factors running in parallel.

1. Viral induced respiratory tract inflammation which causes mild to moderate symptoms, depending very much on dose.

2. Secondary bacterial growth in the oropharynx by a range of bacterial pathogens. These include Staphylococcus aureus, which is toxigenic with various strains secreting pyrogenic toxins, such as toxic shock syndrome toxin (TSST) and staphylococcal enterotoxins (SE). The pyrogenic toxins in turn lead to the production of cytokines, such as tumour necrosis factor (TNF), which has an important role in inducing inflammation [3].

3. The at-risk group in Covid-19 is patients with ischaemic heart disease, hypertension, type 2 diabetes mellitus and obesity. They have pre-existing chronic inflammation which is thought to be directly causative for the conditions [4, 5]. The most likely cause of the inflammation is pathogenic bacteria growing within the tissues. Once again this includes S. aureus.

Patients in whom all three factors apply are at high risk of a cytokine storm leading to severe pulmonary inflammation and a fatal outcome. The cytokine storm is induced by the virus and the bacteria acting together.

S. aureus grows between the squamous epithelial cells of the skin and the oropharynx. We all carry this organism and we all have antibodies that recognise the pyrogenic toxins [3]. The toxins are neutralised by the antibodies in the circulation forming immune complexes; but if the antibodies are saturated then free pyrogenic toxin is present and the cytokine cascade is stimulated. Many patients with Covid-19 who are in hospital and on intensive care will have free staphylococcal pyrogenic toxins in the blood.

We cannot directly suppress the viral induced inflammation but we can prevent the development of the bacterial induced inflammation. The agent is natural yoghurt (live, no added sugar). The lactose fermenting bacteria in yoghurt produce lactic acid which will suppress the growth of bacterial pathogens in the oropharynx. If this is consumed on a daily basis for several weeks the carriage of bacterial pathogens is reduced and those who subsequently meet the virus will have a less severe disease.

In the current epidemic the government should first ensure that the dairy industry can maintain the supply of natural yoghurt on the supermarket shelves. They should then exhort everyone in the population to consume a tub of yoghurt every day. It must be seen as a civic duty; because every spoonful of yoghurt consumed will reduce the amount of S. aureus and other bacterial pathogens in circulation. It will probably take up to four weeks to have an effect but then the severity of newly acquired infections should decrease. The number of hospital admissions will fall, as will the number on intensive care and the number of deaths.

If this strategy succeeds we can get back to normal times.

Professor James A Morris
Consultant Pathologist (retired)
Education Centre, Royal Lancaster Infirmary, Lancaster, UK, LA1 4RP

1. Morris JA, Harrison LM, Lauder RM, Telford DR, Neary R. Low dose, early mucosal exposure will minimize the risk of microbial disease. Medical Hypotheses 2012; 79: 630 – 634.
2. Morris JA. Re-discovering the germ theory of disease: a major role for proteomics. Journal of Proteomics & Bioinformatics 2016; 9: 84 – 86.
3. Morris JA. Staphylococcus aureus bacteraemia: a hidden factor in the pathogenesis of human disease. JSM Microbiology 2017; 5: 1037.
4. Morris JA. Optimise the microbial flora with milk and yoghurt to prevent disease. Medical Hypotheses 2018; 114: 13 – 17.
5. Morris JA. A cacophony of cytokines explains the biopsychosocial interaction model of mental and physical disease. Archives of Depression and Anxiety 2018; 4: 56 – 64.

Competing interests: No competing interests

21 March 2020
James A Morris
Consultant Pathologist (retired)
University Hospitals of Morecambe Bay NHS Trust
Education Centre, Royal Lancaster Infirmary, Lancaster, LA1 4RP