Many people, especially children, are susceptible to colds and flu as the weather turns colder in late March. Taking remedies like Anas barb 200c biweekly or monthly and Calc carb weekly can help strengthen immunity. Aconite is recommended at the first sign of a cold, flu, or sore throat, especially after dry, cold wind exposure, while Gelsemium suits classic flu symptoms and Ferrum phos mild fever and flushed cheeks in early illness.