What is susceptibility to the disease? That anyone who is exposed might get it. The probability decreases significantly in those who already had it (regardless the clinical form, light or severe) and in those who are immune through vaccination or the presence of antibodies capable to attack the SARS CoV19 virus (through previous exposure to very similar viruses ie. small children).
The clinical form depends on a lot of factors (infective dose, length of exposure, other diseases, age) through which is also the immune system.
In general, the more competent this is, the faster will be the production of antibodies and the lighter the clinical form. The individual nutritional status directly influences the immune response.
For several months now there is circulating a prevention and treatment protocol issued by Eastern Virginia Medical School, which although recognizes the lack of strong medical evidence recommends the use of several food supplements: vitamin C and D, quercetin, melatonin and zinc.
Vitamin C (ascorbic acid) can be found in fruit and vegetables. Those should be better eaten raw (high temperature inactivates Vitamin C). Excess can induce diarrhea, nausea, heartburn, abdominal cramps, headaches, insomnia, kidney stones.
Vitamin D is made inside the human body out of food precursors while expose to ultraviolet light (sun exposure) or can be ingested (fatty fish, red meat, liver, egg yolk, fatty dairy products). In excess can cause tiredness, sleepiness, headaches, nausea, vomiting, kidney stones. Supplements should be taken with food.
Melatonin can be found in olives, nuts, seeds, capers, tomatoes, pomegranates, grapes, cucumber.
Quercetin is present in onions, asparagus, grapes, apples, berries, citrus fruit, green tea, coffee.
Zinc can be ingested from oysters, beans, nuts, seeds, whole-grain cereal, dairy products, meat. In excess can cause nausea, vomiting, diarrhea, headaches, abdominal cramps, decreased taste, decreased immunity.
To be well, eat well, be physically active and maintain a safe distance from the others!