Shake Test

What is "Shake test”?
Shake test is used for determining if an adsorbed vaccine has been frozen anytime in the past. The test is valid for "adsorbed vaccines” only, such as DPT, DT, TT, Pentavalent vaccine and Hepatitis-B.

Steps of "shake test”
1. Take the suspected freeze damaged vial.
2. Take another vial of the same vaccine from the same batch and the same manufacturer and label it is as "control.”
3. Deliberately freeze the "control” and then thaw it at room temperature.
4. Shake both the vials vigorously.
5. Place both of them on a flat surface, side by side, against a source of light.
6. Observe and compare the sedimentation rate in both the bottles.
7. If the TEST vial sediments slower than the FROZEN vial then use the vaccine.
8. If the sedimentation is similar in both the vials OR the TEST vial sediments faster than the FROZEN vial then the vaccine is damaged, discard it.1, 2

Figure.1 Both the vials are vigorously shaken and kept side by side—the starting point.

Figure 2 First test vial.

Figure 3 Second test vial.

(Tip to remember in shake test: "Haste makes waste"—faster sedimentation indicates damage. Discard the vial.)

IPV is also freeze sensitive, is ‘shake test’ applicable to IPV too?
NO, shake test is not valid for determining if IPV vial has been frozen anytime. This is so because IPV does not contain aluminum adjuvant.

What is the adjuvant in DPT vaccine?
DPT is adsorbed on a mineral carrier like aluminum phosphate or hydroxide which acts as adjuvant—it is the preferred preparation of choice.

References:
1. GOI. Immunization Handbook for Medical Officers. New Delhi: Department of Health and Family Welfare; 2016.
2. Park K. Principles of epidemiology and epidemiologic methods. In: Park's Textbook of Preventive and Social Medicine, 24th ed. Jabalpur, India: M/S Banarasidas Bhanot Publishers; 2009.

National Immunization Schedule in India; 2017: http://www.ihatepsm.com/blog/national-immunization-schedule-india-2017

Rotavirus vaccine: http://www.ihatepsm.com/blog/rotavirus-vaccine

Pentavalent vaccine: http://www.ihatepsm.com/blog/pentavalent-vaccine

BACILLE CALMETTE GUERIN (BCG) VACCINE: http://www.ihatepsm.com/blog/bacille-calmette-guerin-bcg-vaccine

IPV (INACTIVATED POLIOVIRUS VACCINE): http://www.ihatepsm.com/blog/ipv-inactivated-poliovirus-vaccine

DT & TT Vaccines: http://www.ihatepsm.com/blog/dpt-and-tt-vaccines

Oral Polio Vaccines (OPV): http://www.ihatepsm.com/blog/oral-polio-vaccines-opv

Measles Containing Vaccines (MCV): http://www.ihatepsm.com/blog/measles-containing-vaccines-mcv

HEPATITIS B VACCINE: http://www.ihatepsm.com/blog/hepatitis-b-vaccine

JAPANESE ENCEPHALITIS (JE) VACCINE: http://www.ihatepsm.com/blog/japanese-encephalitis-je-vaccine

Pneumococcal Conjugate Vaccine (PCV): http://www.ihatepsm.com/blog/pneumococcal-conjugate-vaccine-pcv

RABIES VACCINE: http://www.ihatepsm.com/blog/rabies-vaccine