Jan suggested this recipe at the first sign of a cold or flu:

20 drops of  Echinaforce the juice of half a lemon,  a teaspoon of a good Manuka  10+ Honey,  and 1 gram of  Vitamin C in half a mug of hot of water.  You can take this up to 3 times a day, but only take the Vitamin C once.

Clare, my daughter tried it and it worked a treat.