Hi,
It could be eczema, sweat dermatitis, allergic reactions, insect bites or due to friction or tight clothing.
You need to wash the areas several times with fresh water. Do not use any cosmetic products at the sites.
Apply calamine lotion at the site of the lesions and see if it helps. You could take some oral antihistamine medications like cetrizine or loratadine. You need to maintain a good personal hygiene . Wear lose comfortable clothes. Wash all your linen and towels etc with a disinfectant solution.
Anti-itch drugs, often antihistamine, may reduce the itch during a flare up of eczema, and the reduced scratching in turn reduces damage and irritation to the skin.
For mild-moderate eczema a weak steroid may be used (e.g. hydrocortisone or desonide), whilst more severe cases require a higher-potency steroid (e.g. clobetasol propionate, fluocinonide).
Let us know if you need any further information.
It would be advisable to consult a skin specialist for the symptoms and a proper clinical examination.
Let us know if you need any other information and post us on how you are doing.
Regards.
It might be shingles.. but if it's not itching.. it wouldn't be that..you should definitly do to the doctor though..