Do a lab summary of 300 words.

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CAMP test for speciation of Gamma hemolytic species of Streptococcus

Streptococcus agalactiae, a member of the Lancefield Group B streptococci, causes neonatal meningitis, and is one of the causative agents of mastitis in cows. Identifying this organism can be difficult, and the CAMP Test (named from initials of the 4 discoverers) was designed to aid in the identification of this organism. The CAMP test relies on the fact that most S. agalactiae strains produce a diffusible, extracellular compound that will, in conjunction with a specific beta-hemolysin of Staphylococcus aureus, cause complete lysis of sheep red blood cells in an agar medium, resulting in a characteristic “arrowhead” hemolysis (see drawing below), or zone of clearing on a blood agar plate. Said another way, the weak hemolysis of Streptococcus agalactiae synergistically combines with the beta hemolysis of a strain of S. aureus to produce the arrow head shape of beta hemolysis.

To perform the test, apply a single streak of S. aureus across the center of a blood agar plate. Now streak the plate with S. agalactiae perpendicular to the S. aureus, starting at the edge of the plate and streaking toward and to the conjunction of the S. aureus streak. Streaking the other direction will yield confusing results at best. Repeat on the opposite side of the plate with Strep faecalis as a negative control. Incubate the plate at 35-37oC for 24hrs. and observe for presence or absence of the arrowhead-zone of hemolysis. SEE IMAGE “CAMP test for gamma hemolytic Streptococci: left S. salivarius, right S. agalactiae.”

NOTES:

* This test is only used to differentiate species of gamma hemolytic Streptococci.

* For the test to work properly, your streaks perpendicular to the S. aureus streak must originate from a

distance and work toward the S. aureus streak, NOT from the S. aureus streak outward.

S. aureus streak

hemolysis / zone of clearing

S. agalactiae streak