Recent news reports alert us all to the appearance of a new germ, Candida aurans.  Many of the reports are frightening, describing a new infection that is hard to cure, often deadly, spreading across the globe, now in the United States.  But what is this germ, what sort of infections does it really cause, who is at risk, and can it be treated?

Some basics on fungi, yeast, mold, hyphae, and infections with them

Let’s start with what is meant by the word germ.  A germ is a microscopic form of life that enters the body and by growing in the body causes harm, or in other words, an infection.  There are zillions of microscopic life forms, nearly all of them are harmless, a great many are essential to our life and health.  But a handful do grow in our body and cause harm, infect.  Germs come in a small number of types.   The vast majority of germs that we and our children experience are viruses, they cause all the colds and stomach flus.  The other great group are the bacteria, they cause all strep throat, about 2/3 of ear infections, and many other familiar infections.

The new germ, Candida aurans, belongs to a group of germs called fungi.  Fungi actually cause some very common infections, the most common being yeast infections in infants.  Yeast diaper rashes and thrush are all caused by the same fungus, namely, Candida albicans.  The name of this fungus has an interesting set of Latin roots.  Both the word candida and albicans derive from two Latin words that mean the same thing in English, white.  The word candida means white in the sense of very clear, and a familiar English word derived from this sense of white is the word candid.   The word albicans derives from the Latin word for white that suggest whitening.  A familiar English word derived from this sense of white is the word albino.

So, Candida albicans really means white white, and indeed if you grow this fungus on a plate it is very white.  This fungus is relatively easy to kill.  Rub Lotrimin on a rash from this fungus and it clears up, parents have been doing this for a long time for yeasty diaper rashes.  Nystatin painted on the rash from this fungus in the mouth cures thrush.

You may have noticed that we are calling Candida albicans a fungus, but the infections it causes are usually called yeast infections.   It turns out that the word fungus covers several types of fungal life.  If the fungal life lives as individual cells, we call that yeast.  If the fungal life lives as cells connected in a web of fibers, we call that mold.  The web of fibers that some fungi form can create very complex structures, including all mushrooms.

Candida albicans is a fungus that can grow as single cells, yeasts, or as fibrous webs.  In and on the body, this fungus lives mainly as single cells, that is why we call infections with this germ yeast infections.  But if it enters the blood stream and then invades tissues, it can switch to the the web form, but we don’t call that mold in the body, instead we use a more obscure word, hyphae.

Now, Candida albicans is a very, very familiar fungus, and in healthy people never causes internal infections.  You can only get sick from Candida albicans if your immune system is very, very seriously broken.  The overwhelming devastation of untreated HIV, end stages of cancer, the situations caused by powerful drugs that stop the immune system from working, these are the only sort of situations that Candida albicans can cause infections.  So for good reason, we never worry about this germ causing real harm if someone is healthy.

What is this new germ?

As you might guess from the name of it, the new germ Candida aurans, is like Candida albicans, a fungus, that typically lives in the format of a single cell, and so is a yeast, but can form webs of fibers in the body, and when it does is said to be made up of hyphae.

Candida aurans likely evolved as a separate species about 4,000 years ago, but was never seen in a human until 2009, very recently.  That first identification was made from some fungal growth in the ear of a man in Japan, and that is how it got its name aurans, which means ear.  It was never seen to cause internal human infection until 2011, in South Korea, but it has spread across the globe since.

The good news is that Candida aurans so far has caused infections inside the body almost entirely in people with broken immune systems.   So, like Candida albicans, we don’t really have to worry about healthy people getting infected with it.

What infections does it cause?

Again, only if your immune system is not working, Candida aurans can get into a person’s bloodstream and spread to all parts of the body, where it grows, shifting from the single-cell form, to create elaborate webs of fibers that do grave damage.  Tissues affected include the bloodstream, most organs, the brain.

What makes this germ scary are two facts:

1. It is hard to kill.  Most anti-fungal antibiotics fail to kill this germ.  The reason for this state of affairs has been traced to the widespread use of anti-fungal antibiotics in farms across the world, breeding this fungus, Candida aurans, now resistant to the anti-fungals we need to work.
2. It is deadly.  Since so many of our anti-fungals do not kill this germ, it grows unchecked.  Across the world about 50% of people who get infected Candida aurans have died.

How Does it Spread

Here is some more bad news.  All funguses, including Candida aurans, make seeds in the forms of spores.  Spores are very durable, once formed they can sit waiting to take root for quite a long time.  The spores of Candida aurans are no exception.  Once this fungus grows, it can form spores on clothing and sheets, and then be wafted into the air, where it can touch walls and floors and ceilings, attach to these surfaces, and linger, able to infect any time later.  We know this strategy works well because in a few short years, really from its first appearance as an infection in 2011, it has spread from East Asia to around the world.

Right now outbreaks in the United States have been reported, mainly around NYC, but also now Chicago.

Who does Candida aurans infect?

Here is the only good news about this new germ.  It so far has infected mainly people with broken immune systems, broken either from disease such as HIV and cancer or other debilitating diseases.

There have been no epidemics of infections with Candida aurans in healthy people.

This is not surprising.  The extensive and long experience with the fungus Candida albicans teaches us that healthy bodies are mightily well-defended against internal infection with fungi.  Thankfully, the indicators, at least 8 years into our experience with Candida aurans demonstrates healthy bodies defend very, very well, reliably against infection with this new germ.

What Can be Done?

Since Candida aurans is a new germ to the United States, hospitals where it is showing up are considering severe isolation techniques to attempt to stop its spread before it becomes a problem across the nation.  Right now, the state of NY is considering severe isolation regulations for all hospitals in the state of NY so that any appearance of Candida aurans triggers these isolation techniques.

Isolation has a poor track record of halting the spread of disease, except in the case of new germs.  The best example was SARS, a deadly viral respiratory illness that appeared in Hong Kong.   Strict isolation techniques actually  succeeded in halting the spread of this germ, and it is no longer circulating amongst humanity.

BOTTOM LINES

1. Germs are microscopic forms of life that cause harm by entering our body and damaging our tissues.  Most germs that cause illness now are viruses and bacteria.  Many superficial skin infections are caused by another sort of germ, namely the fungus.
2. Many fungi have been around for millenia, we talk about the one that causes diaper rash and thrush, Candida albicans, as an example.
3. Fungi come in at least three forms: single cells (called yeast), webs of fibers (called mold or hyphae), and large webs of fibers assuming myriad complex structures (e.g., mushrooms).  The seeds of fungi are highly durable, and are called spores.
4. A new fungus has appeared and can cause deadly infections, it is called Candida aurans.
5. Candida aurans causes infection mainly in people who are already very ill with broken immune systems.  Healthy people have little to fear from this new germ.
6. Candida aurans was first discovered in 2009, and first seen to cause an infection in 2011.  It is resistant to many anti-fungal medications, likely due to the breeding of resistant fungi through use of anti-fungals on farms.  
7. As a result of the resistance to anti-fungal medications, Candida auranshas so far killed about 50% of those infected.
8. Candida aurans has arrived in the US, with most cases in the NYC and Chicago area, but handfuls of cases have appeared in nine other states, including Kentucky and Indiana, again, in very ill people.

The story of Candida aurans reminds us that widespread use of antibiotics does breed resistant germs, this one now is able to cause grave damage.  We hope strict isolation techniques can keep Candida aurans out of our lives.  Most importantly, healthy people have nothing to fear from this germ at this time.

To your health,
Dr. Arthur Lavin