These precautions are from the Sri Sri Ayurveda Centre, Bangalore.
Tea made from Lakshmi Taru leaves, Tulsi, Amla and Amruth act as an immunity enhancer. Ginger and Turmeric powder mixed either with lime or honey also can be taken twice a day. To counter swine flu viruses Sambrani must be burnt in the house twice a day.
In addition to all this Guruji says that pranayama and meditation increases our immunity. Daily practice of breathing exercises will keep us away from such epidemics