Go to the nearest hospital or call 911 if you develop a stiff neck, have convulsions, experience severe vomiting, experience weakness or paralysis, or become semi-conscious or unconscious. These could be signs of a brain infection like meningitis or encephalitis.  Some patients with mumps can develop meningitis, which may require further medical treatment.  Encephalitis occurs when your brain is inflamed. Left untreated, it can lead to neurological problems and become life-threatening. These could be signs of an inflamed pancreas, or pancreatitis. Bring your child to the nearest doctor if he or she experiences convulsions or if you suspect malnourishment or dehydration. These may be signs of a more serious illness or condition. Mumps during a pregnancy can be dangerous, with an increased risk of miscarriage in the first 12-16 weeks. In rare cases, mumps can cause hearing loss in one or both ears. So if you start to lose hearing in one or both ears, speak to your doctor. They can then refer you to hearing specialist.

How would you rephrase that briefly using Chinese?
要是症状严重，一定要立刻就医。 如果你严重腹痛和呕吐，一定要马上联络医生。 密切观察孩子的状况。 在怀孕期间患上流行性腮腺炎，也要去看医生。 如果你的听力丧失，一定要就医治疗。