What should I do if I develop a rash or skin spots after staying in a hotel in Vietnam?

If spots appear after a night in the room, ask reception to replace the full set of linen—sheet, duvet cover, pillowcases—and all towels. One concern raised was that the bedding may have been turned over during housekeeping rather than changed.

Even if the guest stayed in the hotel all day and it had been rainy beforehand, the cause cannot be reliably diagnosed from a photo or chat messages. Before checking out, photograph the rash and the bedding, report the incident to the hotel, and mention it in a review.

One possible explanation mentioned was photodermatitis—a skin reaction to sunlight rather than bites. As a precaution, wear covering clothing and avoid direct sun; consult a doctor or pharmacist before taking medication, including fexofenadine.

Until the cause is clear, avoid using hotel towels on irritated skin and do not scratch the spots. Seek urgent medical care if the rash spreads rapidly or is accompanied by swelling, breathing difficulty, severe pain, or fever.