Equine antitoxin

Immune sera are sterile solutions containing antibody derived from human (immune globulin [IG]) or equine (antitoxin) sources. 

Drugs There is an antitoxin stored at the CDC. To arrange to use this antitoxin, call your state health department (or CDC at 404-639-2206 or 404-639-3753 workdays, or call weekends or evenings at 404-639-2888). This chemotherapy (antitoxin) available from CDC is a licensed trivalent equine antitoxin for serotypes A, B, and E. There is no reversal of botulism disease with this drug, but the antitoxin does usually prevent further nerve damage. The U.S. Department of Defense (DOD) has a heptavalent equine despeciated antitoxin for serotypes A - G (IND). DOD also has pentavalent toxoid (vaccine) for serotypes A - E (IND). The currently recommended schedule is for use at zero, two, and twelve weeks with a one year booster. This vaccine is supposed to induce solidly protective antitoxin levels in greater that 90 percent of those vaccinated after one year. Contact USAMRIID, (U.S. Army Medical Research Institute of Infectious Diseases), Fort Detrick, Maryland. Tel. 301-619-2833. 

The mainstays of botulism therapy include ventilatory support as well as the administration of botulinum antitoxin. Botulinum antitoxin is a trivalent, equine antitoxin that provides antibodies to botulinum toxin Types A, B, and E. It acts only against unbound toxin and therefore its efficacy is greatest early in the patient s clinical course. Cathartics and enemas have also been recommended for elimination of botulinum toxin from the GI tract. Antibiotics are not recommended except for the treatment of secondary infectious complications... 

The current Centers for Disease Control and Prevention (CDC) therapy for the public is an FDA-approved, bivalent, botulinum equine antitoxin against serotypes A and B. The trivalent antitoxin against types A, B, and E is no longer available. In cases of exposure to any of the other botulinum toxin serotypes, the US Army can provide an investigational heptavalent (ABCDEFG) equine antitoxin, but the time required for typing a toxin subtype would limit its effectiveness in such cases as an outbreak. A parenteral vaccine against the toxin is currently available, but the need exists for newer nonparenteral vaccines that could be administered orally or via inhalation. 

A pentavalent botulinum toxoid (botulinum toxin in different antigenic types) has been used for more than 30 years in some countries to prevent the disease in laboratory workers and to protect troops against attack. Pre-exposure immunization for the general population is neither feasible nor desirable the vaccine is ineffective for postexposure prophylaxis. Treatment of botulism consists of passive immunization and supportive care. Most licensed antitoxins contain antibodies against the most common toxin types A, B, and E. About 9% of recipients of equine antitoxin developed urticaria, serum sickness, or other hypersensitivity reactions. In 2% of recipients anaphylaxis occurred within 10 minutes of antitoxin... 

Plague pneumonia is almost always fatal if treatment is not initiated within 24 hours of the onset of symptoms. A number of readily available, broad-spectrum antibiotics have shown efficacy. Specific broad-spectrum antibiotics are also recommended for post-exposure treatment against tularemia and Q fever. A licensed trivalent equine antitoxin available from CDC is the only approved therapy for airborne botulism. 

Clinicians can obtain licensed equine antitoxin from the CDC through their state and local health departments. The CDC Web site and the Association of State and Territorial Health Officials Web site contain directories for state health departments at http //www.cdc.gOv/other.htm states and http //astho.org. The licensed vaccine is effective against the most common toxin types (A, B, and E) causing human bot-nlism. The US Army has an investigational heptavalent (ABCDEFG) antitoxin effective against other toxin types. However, the time necessary to determine the correct toxin type makes this vaccine less useful in an outbreak (28,36). 

Tacket, C.O., Shandera, W.X., Mann, J.M., Hargrett, N.T., and Blake, P.A. 1984. Equine antitoxin use and other factors that predict outcome in type A foodbome botuhsm. Am. J. Med. 

Foodbome botulism is treated with a licensed trivalent equine antitoxin (serotypes A, B, and E) that is available only from the CDC. There is no other approved therapy for airborne botulism, although animal studies show that botulinum antitoxin can be very effective if given before the manifestation of clinical signs of disease. Mechanical ventilation is invariably necessary due to paralysis of respiratory muscles, if antitoxin is not given before the onset of clinical signs (Shapiro et al., 1997). 

The CDC-recommended therapy for the public is a trivalent equine antitoxin against types A, B, and E. In cases of exposure to other BoNT serotypes, the US Army can provide an investigational heptavalent (ABCDEFG) antitoxin. However, the antitoxins are in limited supply and would need to be retrieved from stockpiles. Therefore, the development of safe and effective postexposure therapeutic compounds for BoNT intoxication is of paramount importance to serve the requirements of the military and civilian populations. In conjunction with drug discovery efforts, there is a parallel exigency to develop appropriate animal models to test the usefulness of various strategies for protection against BoNT intoxication. 

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