All of the following pertain to Neisseria meningitidis except __.
Group of answer choices
virulent factors include a capsule, pili, endotoxin, and IgA protease
causes a serious meningitis
reservoir is the nasopharynx of human carriers
more easily transmitted in day care facilities, dorms, and military barracks
common cause of bacterial pneumonia
The correct answer and explanation is :
The correct answer is: common cause of bacterial pneumonia
Explanation (300 words):
Neisseria meningitidis, also known as the meningococcus, is a Gram-negative diplococcus responsible for serious infections such as meningitis and meningococcemia. It is one of the most important bacterial pathogens affecting the central nervous system, particularly in children and young adults.
Several key features characterize Neisseria meningitidis:
- Virulence factors: It possesses a polysaccharide capsule that helps evade phagocytosis, pili for adherence to host cells, endotoxin (lipooligosaccharide) that can trigger a massive inflammatory response, and IgA protease, which allows the bacteria to evade mucosal immunity. These factors contribute significantly to its pathogenicity.
- Reservoir: The human nasopharynx serves as the natural reservoir. Carriers often remain asymptomatic but can transmit the bacteria to others, especially in close-contact environments.
- Transmission: It spreads via respiratory droplets and is more easily transmitted in crowded environments such as day care centers, college dormitories, and military barracks, where people are in close contact for extended periods.
However, Neisseria meningitidis is not a common cause of bacterial pneumonia. While it can occasionally cause pneumonia, it is not among the leading pathogens responsible for respiratory infections. In contrast, Streptococcus pneumoniae, Haemophilus influenzae, and Mycoplasma pneumoniae are much more frequent causes of community-acquired pneumonia.
Therefore, among the provided options, the statement that “common cause of bacterial pneumonia” does not accurately describe Neisseria meningitidis and is the correct answer to this “except” question. Understanding the typical disease profile and transmission routes of this organism is essential for effective diagnosis, treatment, and public health interventions.