Legionellae are found primarily in aquatic habitats and can infect and multiply within some species of free living amoeba, protozoa, or within biofilms. Legionella infections are acquired exclusively from environmental sources. Inhalations of infectious aerosols is considered the primary means of transmission. Following infection the organisms are taken up by alveolar macrophages where they survive and replicate, evading the hosts immune system. This link provides an animation of L. pneumophila entry into the macrophage.
Pneumonia is confirmed by chest x-ray or clinical diagnosis. The most commonly used laboratory test is the urine antigen test which detects Legionella bacteria in the urine specimen. A documented case of pneumonia and a positive urine test is diagnostic for legionnaire's disease. Diagnosis of legionnaire's disease can also be confirmed with isolation of Legionella pneumophila in culture from a lung biopsy, respiratory secretion, or from various other sites. In addition, paired sera that show an increase in antibody levels when drawn shortly after illness and several weeks following recovery can confirm diagnosis.
For you entertainment, I have added an additional link to a story about a suspected Legionnaire's outbreak at the playboy mansion. There is also a video link to an outbreak in a Miami hotel on the same page, in which there was one fatality.
Good video and interesting link about the hot tub at the playboy mansion.
ReplyDeleteI never knew that you could get a bacterial infection from a hot tub before I took this course. It is interesting that there was an outbreak at somewhere as famous as the playboy mansion. Hopefully this bit of news has helped the general public be more aware of bacteria that can affect them. Maybe more people are more aware of the pH of their hot tub!
ReplyDeleteI, too, had never heard of the hot tub infection until a friend (not pointing any fingers, Jamie) informed me that she refused to get into public hot tubs. Then later on in class we learned of this culprit. Here is an insert from the CDC facts on Legionella(link below):
ReplyDelete'A person can get infected with Legionella when they breathe in steam or mist from a contaminated hot tub. Legionella can also be found in cooling towers, plumbing systems, and decorative pools or fountains.'
After reading this I'm kinda worried about my cooling tower in my bedroom. LOL
http://www.cdc.gov/healthywater/pdf/swimming/resources/legionella-factsheet.pdf
This is not a really common disease, according to the clinical analysis, this disease is caused by the Legionella bacterial, which grow in humid environments.
ReplyDelete