New Vaccine May Protect Horses From Deadly Disease
Streptococcus equi subspecies equi, more commonly referred to as strangles, is one of the most serious diseases effecting horses worldwide. Highly contagious and exhibiting symptoms such as fever, lymphadenitis, and abscesses in the head and neck region, strangles has proven sensitive to penicillin, however, antibiotic treatment has been deemed relatively ineffective as infected animals may harbor the bacteria for several months. Live vaccines have been used for treatment, but often result in serious side effects such as abscesses.
"In order to combat the disease and mitigate serious clinical complications, research has mainly been aimed at developing efficient vaccines," say the researchers.
In the study, mice were immunized with a recombinant subunit vaccine containing parts of the three proteins, FNZ, SFS, and EAG from S. equi either subcutaneously (under the skin) or intranasally (through the nose), and challenged with S. equi through the nasal cavity.
Vaccines in mice had a significant reduction in nasal colonization of S. equi with almost complete eradication in those receiving intranasal vaccination. Healthy horses were then administered the same vaccine intranasally and subcutaneously producing substantial antibody responses against FNZ and EAG. Further enhancement of the antibody response resulted from the addition of EtxB, a form of Escherichia coli enterotoxin and the horses showed no adverse effects to either vaccine combination.
"We found that vaccination with FNZ, SFS, and EAG together gives an antibody response that is highly protective in the mouse," say the researchers. "Thus, these antigens are promising candidates for an effective and safe vaccine against strangles." (M. Flock, K. Jacobsson, L. Frykberg, T.R. Hirst, A. Franklin, B. Guss, J.I. Flock. 2004. Recombinant Streptococcus equi proteins protect mice in challenge experiments and induce immune response in horses. Infection and Immunity, 72. 6: 3228-3236.)
Contact: Jim Sliwa
jsliwa@asmusa.org
202-942-9297
American Society for Microbiology
Nou vaccin pot proteja cai de la boli mortale - New Vaccine May Protect Horses From Deadly Disease - articole medicale engleza - startsanatate