Nothing to Laugh About
● Macabre Mask: The feeding cups of Naegleria fowleri, a single celled protist, may look comical but there is nothing funny about an infection of amebic meningitis: death within a week, with less than 1% survival rate. Fortunately, infections are very rare (“the medical equivalent of being struck by lightning”) although, paradoxically, the amoeba is abundant, living on bacteria in the sediments of warm lakes, ponds and hot springs, where lots of people swim. So relax, you’re not likely to be infected with the “brain eating ameoba”. But how would the amoeba get to your brain, anyway?
● Highway to Hell Or Stairway to Heaven? Water forced up the nose could carry a form of the amoeba (trophozoid) that can get past the lining to the olfactory nerves that detect smells. From there, its a short ride to the olfactory bulb, the only part of the brain with a direct link to the outside world. Once in the brain, the amoeba feeds off cells using its sucker like feeding cups. Research showed that N. fowleri can loosen the tight junctions between lining cells, whereas its non-pathogenic cousin cannot. Some infections have been linked to the use of neti pots to irrigate the nasal chamber. While this ancient practice helps clear symptoms of allergies and colds, it can inadvertently cause amoebic infection. So, always use sterile water.
● Double Duty Drugs: Amebic meningitis is lethal because there are no effective drugs that target this microbe. Antibiotics don’t work. Recently, scientists at UCSF screened a chemical library of FDA-approved drugs and discovered that corifungin, an antifungal, kills Naegleria in a culture dish and in the mouse brain. Based on this, FDA has approved orphan drug status for corifungin to use against primary amebic meningoencephalitis.
Pop Sci/Comic: http://sci-ence.org/the-mucosa-of-oz/
Image: The feeding structures of the amoeba Naegleria fowleri have a face-like appearance. Credit: D.T. John & T.B. Cole, Visuals Unlimited
Open Access Reference: http://goo.gl/Yek2Hu