Final answer:
An unvaccinated child with enlarged parotid glands is most likely to be diagnosed with mumps, which is caused by the mumps virus (MuV) and can include symptoms such as fever and throat pain.
Step-by-step explanation:
If a child unvaccinated comes in with enlarged parotid glands, the most likely diagnosis is mumps. Mumps is a viral disease caused by the mumps virus (MuV), a paramyxovirus, which typically presents with enlargement and inflammation of the parotid glands.
This infection leads to the characteristic swelling between the ears and the jaw. Symptoms of mumps can include fever, throat pain, especially severe when swallowing acidic substances, headache, muscle pain, weakness, fatigue, and loss of appetite. In serious cases, it can cause complications such as encephalitis, meningitis, and inflammation of reproductive organs.
Diagnosis typically involves a physical examination and a confirmation of symptoms consistent with mumps. Since mumps is contagious and a preventable disease through vaccination, this case highlights the importance of maintaining homeostatic balance and the immune system's response to pathogens.
However, without vaccination, the immune system may face challenges in effectively combating the virus, leading to symptoms and potential complications.