Francesca Tomasi received her B.A. from the University of Chicago and is now a microbiologist.
In 1959, an American bacteriologist named Elizabeth King was studying bacteria isolated from children with meningitis. She eventually isolated a previously un-classified microbe and named it Flavobacterium meningosepticum. “Flavo” means “yellow,” an appropriate name for the pale yellow colonies that grew on Dr. King’s agar plates. “Meningosepticum,” as you can probably guess, means “associated with meningitis and sepsis,” the pathologies that led to the isolation of this microbe. Genetic analysis of the bacteria did not place it in any existing genus. As a result, a new genus was named after the Flavobacterium’s discoverer: Elizabethkingia. Now, Flavobacterium meningosepticum’s official name is Elizabethkingia meningoseptica, colloquially referred to as just “Elizabethkingia.”
Chances are you have never heard of Elizabethkingia; and if you have, it probably entered your radar only a couple of weeks ago. After all, Elizabethkingia is rarely implicated in disease: officially, it is classified as a non-fastidious bacterium. Two different species of Elizabethkingia are abundant on Malaysian trees, and the bacteria are also occasionally found in soil and water. Nonetheless, it rarely causes disease. When it does, E. meningoseptica causes fever, shortness of breath, chills, and other flu-like symptoms. It is usually associated with outbreaks of meningitis in infants and newborns in neonatal intensive care units of underdeveloped nations. Sources for these infections have included contaminated medical devices, food, or water. In immunocompromised adults, those whose internal ability to fight infections is hindered by underlying medical conditions, Elizabethkingia is a rare cause of nosocomial infections.
Elizabethkingia is naturally resistant to many typical antibiotics, such as beta-lactams, aminoglycosides, tetracycline, and chloramphenicol. Certain drugs like vancomycin can treat the bacterium, but large quantities of it are required, which calls for alternative treatments due to concerns about side effects and antibiotic overuse. Right now, there are 5 antibiotics that can be used to treat Elizabethkingia: ciprofloxacin, minocycline, rifampin, trimethoprim-sulfamethoxazole, and novobiocin. Rifampin might sound familiar, as it is a go-to drug for people with tuberculosis. Interestingly, Mycobacterium tuberculosis is physiologically quite different from Elizabethkingia.
As you are reading this article, the largest outbreak of Elizabethkingia in public health history is taking place. Usually, the state of Wisconsin records around 5 or 6 Elizabethkingia infections every year. As of March 10, however, an alarming 54-plus people scattered over a dozen counties in Wisconsin have fallen ill with Elizabethkingia. 15 have died, most likely as a result of the infection though this has not been confirmed. There is no obvious connection between these patients other than the fact that most are over the age of 65 and they all have serious underlying health problems. Besides that, some come from hospitals while others haven’t been to one at all. The latter patients became ill at home or in a nursing home.
The outbreak started over four months ago, and authorities are still puzzled about the infection’s source. This is because, so far, none of the usual culprits involved in outbreaks – contaminated food, water, or medical devices – have been isolated. The CDC has dispatched multiple epidemiologists to Wisconsin to interview surviving patients and their families in a collaboration with local health officials. Back in the Atlanta labs, microbiologists are analyzing the genetic makeup of the Elizabethkingia isolated from the Wisconsin patients to search for more clues.
To make matters worse, on March 18 the Michigan Department of Health and Human Services announced that the state saw its first case of Elizabethkingia infection in an older man who eventually succumbed to the illness. If this turns out genetically to be the same strain as the one in Wisconsin, the outbreak has officially crossed its first state border. The CDC has indeed confirmed a common genetic fingerprint between the different samples, which strongly suggests they came from the same source.
To most of us, Elizabethkingia will never pose a threat. However, to immunocompromised patients – old and young – infection could mean a serious illness. As a result, it is of utmost importance to isolate the cause of this current outbreak before it might spread anywhere else, particularly to nursing homes, NICUs, and other vulnerable healthcare settings. The Wisconsin and Michigan public health departments are working closely with the CDC to solve the mysteries of this outbreak.