Pneumococcal pneumonia is a type of bacterial pneumonia that is caused by Streptococcus pneumoniae (pneumococcus). It is the most common bacterial pneumonia found in adults, the most common type of community-acquired pneumonia, and one of the common types of pneumococcal infection. The estimated number of Americans with pneumococcal pneumonia is 900,000 annually, with almost 400,000 cases hospitalized and fatalities accounting for 5-7% of these cases. Symptoms The symptoms of pneumococcal pneumonia can occur suddenly, presenting as a severe chill, followed by a severe fever, cough, shortness of breath, rapid breathing, and chest pains. Other symptoms like nausea, vomiting, headache, fatigue, and muscle aches could also accompany initial symptoms. The coughing can occasionally produce rusty or blood-streaked sputum. In 25% of cases, a parapneumonic effusion may occur. Chest X-rays will typically show lobar consolidation or patchy infiltrates. Treatment In most cases, once pneumococcal pneumonia has been identified, doctors will prescribe antibiotics. These antibiotics usually help alleviate and eliminate symptoms between 12 and 36 hours after the initial dose. Despite most antibiotics' effectiveness in treating the disease, sometimes the bacteria can resist the antibiotics, causing symptoms to worsen. Age and health of the infected patient can also contribute to the effectiveness of the antibiotics. A vaccine has been developed for the prevention of pneumococcal pneumonia, recommended to children under age five as well as adults over the age of 65. Research advancements in the field While it has been commonly known that the influenza virus increases one's chances of contracting pneumonia or meningitis caused by the streptococcus pneumonaie bacteria, new medical research in mice indicates that the flu is actually a necessary component for the transmission of the disease. Researcher Dimitri Diavatopoulo from the Radboud University Nijmegen Medical Centre in the Netherlands describes his observations in mice, stating that in these animals, the spread of the bacteria only occurs between animals already infected with the influenza virus, not between those without it. He says that these findings have only been inclusive in mice, however, he believes that the same could be true for humans. Mechanism of disease manifestation Three stages can be used to categorize the infection process of pneumococcal pneumonia: transmission, colonization, and invasion. The Streptococcus pneumoniae (S. pneumoniae) leave the colonized host via shedding in order to be transmissible to new hosts, and must survive in the environment until infection of a new host (unless direct transmission occurs). Animal models