Which organism causes Rocky Mountain Spotted Fever?

Rocky Mountain Spotted Fever is caused by the organism Rickettsia rickettsii, which is a type of bacteria belonging to the Rickettsiae family. This is an important detail because Rickettsia rickettsii is transmitted to humans through tick bites, particularly from the American dog tick and the Rocky Mountain wood tick.

The disease is characterized by fever, headache, and a characteristic rash that often develops after a few days of fever. Early diagnosis and treatment with appropriate antibiotics, typically doxycycline, are crucial, as the condition can progress rapidly and lead to severe complications if not treated promptly.

The other organisms listed do not cause Rocky Mountain Spotted Fever. Vibrio parahaemolyticus is associated with seafood-related gastroenteritis, Aeromonas hydrophila is primarily linked to wound infections and gastroenteritis, and Streptococcus pneumoniae is a common cause of pneumonia and meningitis. Therefore, identifying Rickettsia rickettsii as the causative agent is vital for the correct management and treatment of this particular disease.