United States Department of Agriculture

CENTER FOR VETERINARY BIOLOGICS NOTICE NO. 15-04

TO: Biologics Licensees, Permittees, and Applicants

Directors, Center for Veterinary Biologics

Veterinary Services Leadership Team

FROM: Byron E. Rippke

CVB Director

SUBJECT: Nomenclature and Level of Identification Required for Leptospira Master

Seed Bacteria and Challenge Cultures.

I. PURPOSE

The purpose of this notice is to inform interested parties of the appropriate nomenclature 

and level of identification required for a Leptospira Master Seed and challenge. True 

Names for the products will remain unchanged.

II. BACKGROUND

Leptospirosis is caused by spirochetes belonging to the genus Leptospira, which

comprises both saprophytic and pathogenic species. Traditional classification specified 

that all saprophytic species are under Leptospira biflexa, while L. interrogans included all 

pathogenic species. The currently used genetically based classification indicates that 

there are at least 19 species (13 pathogenic and six saprophytic) identified through DNA 

hybridization analyses. Seven of these species, L. interrogans L. borgpetersenii, L. 

santarosai, L. noguchii, L. weilli, L. kirschneri and L. alexanderi, are the main agents of 

leptospirosis. More specific identification of Master Seed and challenge will help resolve 

technical difficulties when moving to in vitro testing.

III. ACTION 

A. Master Seed

1. The genus, species, and serogroup should be indicated in Section I of the 

Outline of Production when describing the Master Seed of any product 

containing Leptospira canicola, grippotyphosa, icterohaemorrhagiae, and 

pomona fractions. Identification of the serovar and strain is preferred but not 

required for these Master Seeds.

Example: The isolate is Leptospira interrogans Serogroup

Icterohaemorrhagiae. Restriction enzyme analysis indicates it is serovar 

copenhageni, RGA, or monymusk, but current technical limitations prevent 

more specific identification. 

Animal and Plant 

Health Inspection 

Service

Veterinary Services

Center for Veterinary 

Biologics

1920 Dayton Avenue 

PO Box 844 

Ames, IA 50010

(515) 337-6100

An Equal Opportunity Provider and Employer

BYRON 

RIPPKE

Digitally signed by BYRON RIPPKE 

DN: c=US, o=U.S. Government, 

ou=Department of Agriculture, 

cn=BYRON RIPPKE, 

0.9.2342.19200300.100.1.1=12001

000004093 

Date: 2015.04.02 14:21:51 -05'00'
CENTER FOR VETERINARY BIOLOGICS NOTICE NO. 14-15

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2. The genus, species, and serovar should be indicated for products containing 

Leptospira hardjo and Leptospira bratislava fractions. Identification of the 

strain is preferred but not required for these Master Seeds.

Example: The isolate is Leptospira borgpetersenii serovar hardjo-bovis strain 

93U.

3. New Master Seed Bacteria (MSB) must be identified to the serogroup or 

serovar level as indicated above. For existing approved MSB, this information 

should be added to the Outline of Production. Working seeds may be used for 

identification. Firms should contact their reviewer for specific guidance.

B. Challenge

A biological product containing Leptospira fractions that is potency tested 

through a hamster vaccination-challenge assay must have the challenge used in 

the potency assay indicated in Section V.C. of the Outline Production in 

accordance with VS Memorandum 800.206. Likewise, the challenge used in 

efficacy studies for products containing Leptospira fractions must be indicated.

1. The genus, species, and serogroup should be indicated for challenge used to 

test products containing Leptospira Serogroups Canicola, Grippotyphosa, 

Icterohaemorrhagiae, and Pomona. Identification of the serovar and strain for 

the challenge is also preferred but not required.

2. Nomenclature Changes – The CVB has adopted the following nomenclature 

for the Leptospira challenges supplied to stakeholders for potency tests 

codified in 9 CFR 113.101 – 113.104:

Current designation Proposed designation

Leptospira canicola Leptospira interrogans Serogroup Canicola

Leptospira grippotyphosa Leptospira kirschneri Serogroup Grippotyphosa

Leptospira icterohaemorrhagiae Leptospira interrogans Serogroup Icterohaemorrhagiae

Leptospira pomona Leptospira interrogans Serogroup Pomona

The CVB will revise this nomenclature in SAMs, reagent data sheets, and other

documents.

3. The genus, species, and serovar should be indicated for challenge used to test 

products containing Leptospira hardjo and Leptospira bratislava fractions.

Identification of the strain is also preferred but not required.

An Equal Opportunity Provider and Employer

15-04
CENTER FOR VETERINARY BIOLOGICS NOTICE NO. 14-15

Page 3

IV. IMPLEMENTATION/ APPLICABILITY

Annual review of Outlines of Production is required as per 9 CFR 114.8(d). As this 

occurs, Section I and Section V should be updated to reflect the current naming 

convention. It is expected that documents will be in compliance with the nomenclature 

update within 18 months of publication of this notice. If additional time is needed, firms 

should request additional time from their reviewer prior to the deadline and supply a time 

line for their compliance.

An Equal Opportunity Provider and Employer

15-04