Chau, a 3-year-old girl, developed a boil on her nose that spread to both eyes, leading doctors to diagnose a staphylococcus aureus infection.

Ms. Phong, 73, experienced high fever, shortness of breath, and frequent urination due to pyelonephritis with bilateral renal abscesses, leading to a systemic infection.

Uyen, 66, experienced vomiting, diarrhea, and low blood pressure. A blood culture confirmed salmonella infection, leading doctors to suspect food poisoning from rice left overnight in the refrigerator.

Ong An, 79, experienced high fever and painful urination for several days, leading doctors to diagnose infective endocarditis with a vegetation on a heart valve.

My one-year-old has had bronchiolitis for over 10 days and is not recovering. Do I need to give my child antibiotics? (Mai Huong, Hanoi)

Hai, 35, experienced chest pain and fever after treatment for acute tonsillitis, leading doctors to diagnose myocarditis and acute heart failure caused by the infection.

Cuong, 13 years old, presented with fever, productive cough, hives, and whole-body swelling, leading doctors to diagnose bronchitis and an allergic rash caused by an infection.