Gram-negative Bordetella Bronchiseptica

This scanning electron micrograph (SEM) depicted a number of Gram-negative Bordetella bronchiseptica coccobacilli bacteria. This organism is commonly found to be the cause of respiratory tract infections in dogs, as well as human beings whose immune system had been compromised including those who are infected by the HIV virus. Genetically very similar and closely related to B. pertussis, which is evidenced in the fact that it too possesses the gene to express pertussis toxin, this Bordetella member does not produce the toxin like its fellow genus member. This bacterium can cause a wide range of symptoms, including mild respiratory illnesses such as rhinitis, to those indicative of full-blown pneumonia, with accompanying ?pertussis-like? manifestations, especially in immunocompromised individuals, as in the case of those with an HIV infection. Image courtesy CDC/Janice Haney Carr. 1982. (Photo by Smith Collection/Gado/Getty Images).