1. K V M COLLEGE OF PHARMACY
ACADEMIC YEAR 2020-2021
SCHICK TEST
PREPARED BY : VAISHNAV SR
VANDHANA G DEPT : MICROBIOLOGY
SECOND PHARM D
2. TABLE OF CONTENTS
• INTRODUCTION
• PRINCIPLE
• PROCEDURE
• RESULT INTERPRETATION
3. INTRODUCTION
• Schick test is invented between 1910-1911, a test used to determine whether or
not a person susceptible to diphtheria and causative agent
is Corynebacterium diphtheriae. It was named after its inventor Bela Shichk
(1877-1967), Hungarian born American paediatrician. It is an intradermal test. The
test is carried out by injecting intradermally into the skin of forearm 0.1 ml of
diluted (1/50 MLD) diphtheria toxin, while into the opposite arm is injected as a
control, the same amount of toxin which has been inactivated by heat.
4. DIPHTHERIA
• Diphtheria is a serious infection caused by strains of gram positive bacteria called Corynebacterium
diphtheria that make toxin (poison). It spreads easily from one person to another , diphtheria can be
prevented through the use of vaccines .
• Signs of diphtheria often appear within two to five days of the infection occurring . Some people don’t
experience any symptoms . The most visible and common symptom of diphtheria is a thick , gray
coating on the throat and tonsils .
• Other common symptoms are ;
• Fever
• Chills
• Sore throat
• Difficulty breathing and swallowing
• A loud , barking cough
5. PRINCIPLE
The Schick test works by injecting intradermally into the skin of forearm 0.1 ml of
diluted (1/50 MLD) diphtheria toxin. If the person is susceptible to the disease, a red
swollen rash appears around the injection area.
7. OBSERVATION OF RESULT
• Check redness/erythematic production and measure the zone of reaction in mm.
8. RESULT INTERPRETATION
• Negative reaction: If a person had immunity to diphtheria, no reaction will be
observed on either arm.
• Positive reaction: An area of in duration 10-15 mm in diameter generally
appears within 24-36 hours reaching its maximum development by 4-7 days, the
control arm shows no change. The person is susceptible to diphtheria.
• false positive reaction: A red flush develops in both arms, the reaction fades
very quickly, and disappears by 4th day. This is an allergic type of reaction found
in certain individuals
• Combined reaction: the control arm shows pseudo positive reaction and the test
arm is true +ve reaction, susceptible and need vaccination.
9. KEYNOTES
• Schick test is not indicated in very young children as they are susceptible and
require immunization
• No reaction – Protective immunity present.
• This test is now out dated due to vaccination and eradication.
• It also called toxigenic test.
• MLD stands for minimal lethal doses
