Meningococcal refers to infections caused by the bacterium Neisseria meningitidis, which can lead to serious conditions like meningitis and septicemia. This bacterium is often found in the throat and nose of healthy individuals but can spread through respiratory droplets. Vaccines are available to protect against several strains of Neisseria meningitidis, making vaccination important, especially for adolescents and young adults. Early symptoms of meningococcal disease can include fever, headache, and a stiff neck, and prompt medical attention is crucial for effective treatment.