Brief Answer:
I will suggest a likely possibility of Genital Herpes

Detailed Answer:
Hello. Thank you for writing to us at healthcaremagic

I have gone through your query and I have also seen the Image.

I can see cluster of fluid filled lesions/vesicles In this Image.

I would keep a possibility of Genital Herpes.
Genital Herpes classically presents with grouped discrete fluid filled lesions which rupture to form erosions. The lesions may be painful and there may be a burning sensation.
Genital Herpes is an STD.

Regards

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Brief Answer:
Treatment of herpes is with Oral antivirals

Detailed Answer:
Hi.

Genital herpes is treated with Oral antivirals e.g Acyclovir Or Valacyclovir for a week.
Oral antivirals are prescription drugs. I suggest him to visit a specialist for counselling and testing for all STD's including herpes as well as for a prescription for the same.
Topically you may use an OTC topical antibacterial e.g 2% mupirocin ointment, twice daily.

Regards

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