While a stiff neck and sore throat may result from having one's head in an uncomfortable position along with snoring or breathing through the mouth during sleep, the causes may also be viral or bacterial. Viral meningitis, mumps and mononucleosis are virus-based causes of a stiff neck and sore throat. Strep throat is a bacterial cause of these two symptoms.

Strep throat is very common in children although adults can also get it. The Streptococcus (strep) bacterium can be easily transmitted to others through coughing or sneezing since the bacteria of an infected person is in the nose and mouth. Hand washing may prevent transmission, but strep throat is highly contagious. In young children, an early symptom of strep throat may be refusing food due to pain when swallowing. Fever, vomiting and headache are other common symptoms of strep in addition to muscle soreness, a stiff neck and sore throat.

Strep throat pain usually feels more severe than that caused by a cold or other virus. Since the cause is bacterial, antibiotics are required to treat it. It's especially important to get children who are thought to have strep to a doctor within 10 days of the onset of symptoms or acute rheumatic fever, which is thought to lead to heart disease, may result. Adults should also get antibiotic treatment for strep throat, although they are not as likely as children to develop acute rheumatic fever.

Mononucleosis (mono) is another common cause of a stiff neck and sore throat. In this condition, which is often caused by the Epstein Barr virus, swollen lymph nodes in the neck can become quite painful. Mono is called the "kissing disease" as it's often passed on to others from germs in the mouth. It may also be transmitted from a cough or sneeze. Teens especially are susceptible to mononucleosis which may begin with fatigue, headache and a fever.

Mumps symptoms often include difficulty swallowing. Mumps often causes muscle aches and earaches as well. Nausea, a stiff neck and sore throat are also often caused by mumps. One of the complications of mumps is viral meningitis.

Viral meningitis is a brain infection that may cause a stiff neck and sore throat. Other common symptoms are fatigue, headache and fever. Although anyone can get viral meningitis, it's another one of the medical conditions that is more commonly seen in children. Other than a complication of mumps, viral meningitis may be caused by intestinal viruses.