Hospital based outbreaks of infectious disease are nothing new and have haunted hospitals for hundreds of years. Indeed horrific outbreaks of childbed fever in Austria were what prompted the revolutionary studies of Semmelweis on the power of simple hand-washing.
While hospitals have modernized and are often associated with that particular sterile smell--when I was child I loved to sniff my mom's lab coat--they are chock full of microbes waiting to pounce. MRSA, norovirus, C.diff, VRE, Legionella, Acinetobacter, ESBLs, and CRE abound in hospitals and cause over 800,000 healthcare-associated infections annually with 75,000 of those ending in death.
As I often say, we live in a world of microbes and they are literally everywhere -- including hospitals, no matter how clean and no matter how modern. News of mold being present in a hospital in Pittsburgh (on which I am on staff) may seem alarming, but it is not unprecedented as hospitals are part of our microbe-laden planet.
Molds are types of fungi (see graphic) that grow in a certain manner, forming hyphae or little branches. Yeast, the other type of fungi, grow in a different manner forming buds. Some fungi are dimorphic and can switch between the two forms. The most famous mold is probably Penicillium from which penicillin was derived, changing the trajectory of medicine forever. Molds can be found in your fridge, in your basement (the medically unimportant "black molds"), and basically everywhere you look -- if you see them on your favorite cheese you can often just separate that portion of the cheese and the rest will be perfectly edible.
Other medically important molds include Aspergillus, Scedosporium, Fusarium, and Exserohilum. This last was recently in headlines after a nationwide outbreak of fungal meningitis occurred after steroid vials were contaminated during manufacture.
Mold infections can range from infection to the lung to disseminated infection throughout the body--an often fatal event. Symptoms such as difficulty breathing and skin lesions can be present either as result of dissemination from the blood or from direct infection of a skin breach (e.g. after the Joplin tornadoes individual impaled with debris developed Mucor infections). Each mold has its own specific predilections and associated clinical course, some more severe than others, and some more amenable than others to anti-fungal treatments.
Healthcare-based outbreaks of molds are a rarity but have occurred. Some recent cases include:
- An ongoing CDC-led investigation of a multi-state outbreak of Bipolaris infections in cardiac surgery patients many of whom had open chest wounds for an extended peroid
- A 6 person Aspergillus outbreak associated with a contaminated air-handling system
- A single fatal case of Rhizopus tied to a contaminated probiotic supplement at a Connecticut pediatric hospital
- A hospital-based outbreak of 5 fatal cases of Rhizopus tied to contaminated bed linens at a Louisiana pediatric hospital
- Ophthalmologic mold infections tied to contaminated injections
Mold infections are not the usual nosocomial infection and often can only infect those with a high degree of immune system compromise. Because of that fact these infections are thankfully fairly delimited but, because of the overall condition of those susceptible to such infections, can prove to be very severe, as seen in the outbreaks mentioned above. The general public or hospital staff has nothing to fear from these occurrences.
The large scale of the steroid injection fungal meningitis outbreak is the exception that proves the rule as its mechanism of entry into the body involved a major assist in breaching the major component of the immune system: the skin.
Hospitals are constantly vigilant for patient safety from molds and other microbes, and though there is variation in the ability of individual hospitals to deal with such situations, I am completely confident that this latest situation is being handled expertly.