No, generally speaking, letters to editors will not be marked as "original papers" because ordinary letters are unlikely to be original. However, many units classify the Letter to the Editor as a SCI paper, especially the letter published in first-class journals such as NEMJ. It is true that all the people who can send letters are cattle, but this short and quick way and hard work on the subject, and finally publishing an original paper actually enjoys the same treatment, and sometimes it is unfair. According to the calculation of SCI impact factor, letters are not included in the denominator, which means that letters generally do not belong to papers.