Septicemia

• Casano, Charyze Joy G wrote a written report titled "VMED 70: Hemorrhagic Septiceemia" with the etiology, transmission, and causative agent being Pasteurella multocida serotypes B:2 and E:2, which correspond to serotypes 6:B and 6:E of the Namioka - Carter classification system.
• Pasteurella multocida is one of the most prevalent commensal and opportunistic pathogens living in the oral, nasal, and respiratory cavities of animals.
• The transmission of Pasteurella multocida occurs through contact with infected oral or nasal secretions from either healthy carrier animals or animals with clinical disease, or by ingestion of contaminated feed or water.
• Infection with Pasteurella multocida begins in the tonsil and adjacent nasopharyngeal tissues.
• Bacteremia leads to dissemination and rapid growth of bacteria in various locations, tissue injury, a host cytokine response, and release of lipopolysaccharides that results in a rapidly progressing endotoxemia.
• Clinical signs of Hemorrhagic Septiceemia can appear 1 – 3 days after infection, and death can occur within 8 – 24 hours after the first clinical signs develop.
• In endemic areas, Hemorrhagic Septiceemia affects older calves and young adults, and morbidity and mortality are variable.
• In nonendemic areas, epizootics of Hemorrhagic Septiceemia can occur with high morbidity and mortality that can reach 100%.
• Water buffalo tend to have higher morbidity with more severe clinical disease than cattle.
• Alum-precipitated and Aluminum Hydroxide Gel Vaccines are commonly used and have a shorter duration of immunity of 4 - 5 months with variable protective efficacy.
• Oil Adjuvant Vaccine is administered annually and is most effective when administered 1 month before the monsoon or rainy season.
• Attenuated or Modified-Live Vaccines are associated with sporadic outbreaks and virulence in young animals.
• Intranasal Vaccine is associated with sporadic outbreaks and virulence in young animals.
• Oil-based vaccines combined with polysorbate 80 or saponin can increase the ease of administration or immune protection.
• Sulfonamides, Tetracyclines, Penicillin, Gentamicin, Kanamycin, Ceftiofur, Enrofloxacin, Tilmicosin, and Chloramphenicol are effective antimicrobials for treatment of hog sickness.
• Booster for Alum-precipitated and Aluminum Hydroxide Gel Vaccines is twice yearly and is made from the strain of Pasteurella multocida circulating in the regions of intended use.
• Plasmid- and chromosomal-mediated multidrug resistance is increasing for some strains of Pasteurella multocida.
• Failure of vaccination is common due to inadequate vaccine coverage.
• Diagnosis of hog sickness is typically made based on clinical signs and lesions, but laboratory diagnosis can be done through culture and blood tests, isolation of Pasteurella multocida serotype B:2 or E:2 from the blood and tissues, and more precise tests such as indirect hemagglutination test, coagglutination test, counter immunoelectrophoresis test, and immunodiffusion test.
• Bacterins, alum-precipitated and aluminum hydroxide gel vaccines, and oil-adjuvant vaccines are types of Killed Vaccines.
• Molecular techniques for diagnosis of hog sickness include pulsed field gel electrophoresis, southern blots, loop-mediated isothermal amplification, and PCR-based protocols.
• Hemorrhagic septicemia in water buffalo and cattle is a generalized condition.
• Acute disease of hog sickness lasts up to 3 days and less often up to 5 days and clinical findings include fever (40 o - 41.1 o C), apathy or restlessness and reluctance to move, hypersalivation, lacrimation, nasal discharge, and subcutaneous swelling in the pharyngeal region, ventral neck, and brisket.
• Patients over 3 years old require initial 2 doses, 1 - 3 months apart, and a booster once or twice yearly.
• Peracute cases of hog sickness result in death within 8 - 24 hours and clinical findings include fever, hypersalivation, nasal discharge, and labored respiration.
• Lesions of hog sickness include swelling of the subcutis and muscle of the submandibular region, neck, and brisket, with clear to blood-tinged edema fluid, serous to serofibrinous fluid in the thorax, pericardium, and abdominal cavity, and widespread congestion with petechiae and ecchymoses in tissues and on serosal surfaces.
• Resistance to tetracyclines and penicillin has been reported for serotype B:2.
• Treatment and prevention of hog sickness involves antimicrobials, effective if administered early, and during outbreaks, any patient with IV antimicrobials.
• Maternal immunity can interfere with Alum-precipitated and Aluminum Hydroxide Gel Vaccines.
• Killed Vaccines are most commonly used for prevention.
• Recovery from Hemorrhagic Septiceemia can stimulate acquired immunity to homologous and often heterologous strains of Pasteurella multocida, and some of these animals become healthy carriers that can be a source of infection for future outbreaks.