What%20are%20germs%3F%20How%20do%20they%20spread%3F%20And%20how%20do%20medicines%20help%3F%20Curious%20young%20children%20can%20take%20a%20closer%20look%20at%20those%20mischievous%2C%20microscopic%20bacteria%20and%20viruses%20in%20this%20fascinating%20introduction%20to%20germs%20and%20hygiene%2C%20with%2030%20flaps%20to%20lift%20and%20tips%20on%20hand-washing%20and%20staying%20healthy.%20Written%20with%20advice%20from%20Public%20Health%20England.