Brief Answer:
External factors can cause this, nothing to worry about :)

Detailed Answer:
Hello and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. Even hygienic individuals some times do not give the navel as much attention as it deserves due to its presentation.

Dust, shreds from cloth, sweat, etc; can all accumulate in the navel which is a breeding ground for bacteria to grow, multiply and eventually result in an infection. Although not very commonly seen (due to the region being obscured by clothing), this infection is quite commonly encountered in the medical setup.

The simple reason being the above, and this is nothing to worry about, and should clear up with a course of antibiotics, proper drainage, good dressing, and can be prevented by simple measures aiming towards better care and hygiene of the navel.

I hope you find my response helpful. Please feel free to write back to me for any further clarifications, I am always here to help.

Best wishes.

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