In the absence of sensible local recommendations use the recommendations yourself of the most successful region in fighting Covid-19 (Helsinki, Finland) 

Daily:

• Overweight people with a body mass index of more than 30:    60 mcg or 2200 IE  (E.g. a 2000 IE tablet per day and an occasional extra tablet) 

• Non overweight white adults 20 mcg or 800 IE  (E.g. 1000 IE tablet approximately every day)

• Non overweight colored people, non-overweight people in elderly care or 24 hour care or non-overweight people over 70:  30 mcg or 1200 IE (E.g. 1000 IE tablet per day and an extra table once or twice per week)

D vitamin is stored in the body so theoretically one could take it weekly but 7 times more.   However there is considerable evidence that it is more effective to take it daily.   There is also new evidence that side effects are reduced if taken daily rather than weekly.    A compromise approach is if you have a tendency to forget to take the daily dosage to sometimes take more.  No need to buy the relatively more expensive mega tablets, just take more smaller tablets.   

Use those recommendations yourself and recommend to your friends and family.   Ask your doctor or pharmacist and point him to this page to be sure.  Please note these recommendations are rather conservative and we have heard doctors recommended higher amounts particularly at the beginning.  Other doctors might recommend lower amounts but we think during the time of the pandemic it is better to take a little bit more rather than less.  Do not take too much as this can be dangerous!

(Given that the people of Finland are already getting 10 mcg, 400 IE (International Units) in a liter of milk, we have upped the advice above by this amount)

It would be advisable to take some of this Vitamin-D in the form of Cod Liver Oil, just make sure you do not exceed the recommended Vitamin-A levels.  Cod liver oil includes healthy Omega-3 which is thought to have a positive effect on Covid-19 as well.   However make sure you are NOT getting too much Omega-3 (Other sources of Omega-3 are fish and rapeseed/canola oil.  Get the right balance with Omega-6 found in Sun Flower Oil or even Omega-9 found in Olive Oil) as otherwise it may lead to other problems such as bleeding, stomach ache and dementia.  If you are getting bruised easily that may be a sign of too much Omega-3.    

You can lower your intake of Vitamin-D if you get enough strong sun exposure without UV protection, if you eat a lot of fish (e.g. approaching 1 kg per week) or if your skin complexion is not much paler than in the summer when you get good sun exposure.

If you have a balanced diet you do not need to take any other Vitamins or minerals.  Make sure you get enough green vegetables and some fresh nuts so that you get enough Magnesium (bananas and almonds are good).  Your body can create its own Vitamin K from deep green vegetables.   Vitamin A you can get enough of if you take Fish Liver Oil, otherwise you can get it in Carrots and green vegetables.   Having enough of Vitamin A or K or Magnesium reduces or eliminates the side effect of Vitamin D which is having too pure bones.  (Taking Vitamin D regularly rather than only occasionally in huge dosages also reduces this risk.)  Calcium which you can get from Milk works with Vitamin-D to create healthy bones.  

You could reduce your dosage if you experience unhealthy loss of appetite or sleepiness, dry mouth, weakness, fatigue, headache, metallic taste, nausea or vomiting.  When you crossover from being Vitamin D deficient to having enough Vitamin D expect that your body will renew your bones, making you more fragile while this process is going on. 

Do NOT take extra Zinc as this may permanently damage the copper in your heart unless it is monitored by your doctor.   If you eat some fruits you do not need to take Vitamin-C and if you get infected with the virus STOP taking Vitamin-C as it may kill you.   It is known to increase the likelihood of death in Intensive care by 360%.   (There has been some false information spreading on the Internet suggesting the opposite)

Here is what you can do for your town, country and the whole world:

If this advice is restricted to your friends and family it will do nothing to ease the lockdowns.  Only when everybody takes this advice will the pressure on the hospital systems be reduced enough for the authorities to let us return to normality!  This is why we need your help in distributing our message not just to your friends and family but that everybody. Please forwards this message on.   That way we will eventually also reach some politicians and/or famous and influential people who can really make a difference in spreading our message.