maybe. Historically speaking, at least with similar viruses, the flu for example, skyrockets in the winter because everyone is inside and generally speaking, closer together. plus the holiday get togethers and such. They say vitamin D helps and sunlight is a good source of it, so that's one reason the doctors my wife works for have always recommended going with Vitamin D milk and supplements during the winter months. We switched 8 years ago to it and rarely ever get sick in the winter.