Microtek Vaccines

The first scientific attempts to control an infectious disease can be attributed to Edward Jenner, who in 1796 inoculated an 8-year-old boy with cowpox, providing the boy with protection against virulent smallpox. Thanks to the successful development of vaccines, many major human diseases are today kept under control, and in the case of smallpox the dream of eradication of a disease has been fulfilled worldwide.

Traditional vaccines are still based on Jenner's idea, and many vaccines used routinely are either killed, whole-organism (bacteria or viruses) vaccines, or live attenuated (weakened or crippled) bacteria or viruses. Examples killed, whole-organism vaccines developed by Microtek Research & Development are ADVANTIGEN^TM 5.1 and MICROVIB.

Subunit vaccines employ partially or fully purified molecules from pathogens (proteins, LPS, carbohydrates etc.). These types of vaccines are usually designed to minimize potential undesirable reactions that may occur with traditional vaccines. Subunit vaccines frequently are also more effective.

Recombinant vaccines are subunit vaccines produced by new methods. Once a molecule that can produce specific immunity is identified among the thousands of components in pathogenic microorganism, recombinant DNA methods are used to produce this protective antigen in a safe nonpathogenic microorganism such as Escherichia coli or yeast. This makes it possible to produce vaccines even when the pathogens are difficult or impossible to cultivate. There is absolutely no possibility that the living pathogen (bacteria or virus) would be present in the recombinant subunit vaccine. This approach is already well established in human vaccinology with the first subunit recombinant vaccine, the hepatitis B surface antigen produced in yeast, approved in 1986. The first recombinant injectable vaccine developed by Microtek Research & Development is Bayovac^® SRS licensed for export to Chile where it is used with great success to combat Salmonid Rickettsial Septicemia.

Vaccination against diseases of farmed aquatic animals

Vaccination by injection is currently the most widespread and the most effective method of vaccine delivery for long-term protection in fish. Vaccination by immersion is less stressful to the fish and less costly for the producer, because there is less handling. Immersion is primarily for use in protecting younger and smaller fish from disease outbreaks in the hatchery, or for priming the immune system prior to further vaccination by injection. Oral delivery of vaccines (by mixing in the feed) is the ultimate goal in aquatic vaccine design. Microtek is working on a cost effective oral vaccine design that will provide the long-term protection obtained with injectable vaccines.

Vaccines may be formulated as monovalent (one disease target) or multivalent (two or more disease targets).

Vaccines for IP injection can be delivered using fish vaccination machines; more info...

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