Further investigation revealed the boy's grandmother had developed herpes zoster 2 weeks (index herpes zoster patient, Case 5) before the illness of the boy's sister (Case 2). The 57-year-old grandmother suffered from herpes zoster on her chest, back, and axilla. She had no history of tuberculosis, HIV, Hepatitis B or C, or other immunocompromising diseases. She consulted a private Chinese medicine clinic, and her zoster resolved with traditional Chinese medicine treatments for 2 weeks. The grandmother had been taken care of the children and slept with them.