What are the advantages of being a respiratory parasite (the tongue worms) over one in the digestive system (if any) ?

The parasites living at the respiratory system or tongue worms will hide under the soft tissues of the oral cavity, beneath the tongue and even beneath the throat or esophagus. These worms remain undetected during diagnosis. These worms are not subjected to the treatment of acids which worms in the digestive system are exposed to. Thus these worm parasites in the respiratory system or tongue survive comparatively for long as compared to the worms in the digestive system.