Although the viruses that cause laryngitis, such as the common cold virus, are contagious and can be passed from person to person, usually the contagious period for the common cold is earlier on in the infection, before symptoms begin and when the cough and congestion symptoms are at their height.lso mechanical strain (singing or talking) are common non infectious causes of laryngitis. Obviously, mechanical laryngitis is not infectious or contagious. Viral laryngitis, which is the next most common form, is also not usually contagious.