In science fiction, enemy invaders are usually repelled by armed combatants. They are kept out and there is little inner resistance. This may not be the situation with coronavirus attacks. COVID-19 virus particles try to invade human bodies but are opposed by immune systems armed with killer T cells, phagocytes and lymphocytes. 4200 infections of 6612 cases in Australia have recovered, with 72 deaths, Presumably, the other 2340 cases are being treated or possibly quarantined. Many of the recoveries would be attributable to immune systems that have successfully fought off viral pathogens, with or without medical treatment. Bechamp (1806-1908) was the first to theorize strengthening of immune responses with diet, hygiene, fresh air and exercise. Assiduous attention to these could be as important to flattening the curve as have been social restrictions and medical treatments.
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