Brief Answer:
It is a good sign showing that treatment has worked.

Detailed Answer:
Hello dear, welcome Ask a doctor's service.
I read your query and here is my advice.

I see the picture you uploaded and three round warts are seen and black skin is seen around them.
The fact that the skin turned black means that the treatment is working and the warts will fall soon in 4 to 7 days and scar will remain there. As the warts fall you have to disinfect the scar with alcohol in order not to get infected.
The black skin around warts is a good sign showing that treatment has worked.


Hope I have answered the question.
Let me know if I can assist you further.

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Brief Answer:
Covering it doesn't affect healing process.

Detailed Answer:
Hello dear and thank you for asking again.
Covering it will not affect the healing process. You can cover it if you want.

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