Staying healthy at this end of the year, is usually about keeping warm and well fed.
This year the persistent wet warmth is encouraging horrible little organisms to spread, mutate and gain strength. Staphyloccoccous (feels like a fluey type cold) and Pseudonomous (makes you feel so tired, really fatigued, not just ordinary weary).
Difficult to get them diagnosed without lab tests, but you can do something if you suspect either of these. High doses of Vitamin C ( I take 10 grams a day) No harm, kidneys just flush it out in a couple of hours, so spread the dose throughout the day. Remember Linus Pauling showed what an excellent cancer prevention this was, and sometimes took a lot more than that!
For Pseudonomous, your homeopath can probably help, but take some iron for a couple of weeks. This bug uses up your iron reserves which is what makes you so tired, and you need to put that back. There is a side effect of iron, often reported by pregnant women, which is that of temporary constipation! So to counteract that, nibble a couple of organic dried figs daily for a snack!