The viral coat as chocolate? The linked article has a list of why the flu is more common in the winter months. One idea discussed in the article is the characteristics of the viral coat. As the temperature drops the coat get harder, as the temperature increases the coat become gooey and soft, much like chocolate does when the temperature changes.
METAMIA is a free database of analogy and metaphor. Anyone can contribute or search. The subject matter can be anything. Science is popular, but poetry is encouraged. The goal is to integrate our fluid muses with the stark literalism of a relational database. Metamia is like a girdle for your muses, a cognitive girdle.