Skip to main content
U.S. flag

An official website of the United States government

Here’s how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

This is a preview of updates coming to the Technical Bulletin's website in April 2026. Return to current site.
Read more about the modernization release schedule in this announcement.
Comment via the yellow feedback button in the lower right hand corner of the page. Contact the NLM Help Desk with any questions or concerns.

This is archived content.

Links may have become inactive over time. Visit Archive-It   to find the original published layout.

NCBI Taxonomy Identifiers Added to MeSH

Cho, D. NCBI Taxonomy Identifiers Added to MeSH. NLM Tech Bull. 2020 Nov-Dec;(437):e2.

December 04, 2020 [posted]

In 2018, MeSH began adding NCBI taxonomy vocabulary into MeSH, starting with Virus terminology. This project has since been expanded to include Archaea, Bacteria, and Fungi. In 2020, MeSH began adding the NCBI Taxonomy ID numbers (txid) to the Registry Number (RN) field of the MeSH Supplementary Concept Records (SCRs), starting with the Class 4 SCRs (Organisms). For 2021 MeSH, the project included the addition of txids for MeSH Descriptors in the Category B1-B4 Organisms tree. While the Registry Numbers do not display for these Organisms terms in the MEDLINE citations, users will be able to see the RN number in the MeSH Browser display. For example, SARS-CoV-2 has Registry Number txid2697049 from NCBI Taxonomy.

Note that MeSH continues to map SCR organisms to MeSH headings (Heading Mapped To [HM]) and provides additional references to related MeSH headings, such as infectious diseases caused by the organism. For example: