(CNN) A 49-year-old Pennsylvania woman showed the presence of a rare kind of E. coli infection, the first known case of its kind in the United States. It is a superbug that is resistant to many antibiotics, even Colistin, which doctors use as a last resort when other antibiotics fail.
The case was detailed in a report by the U.S. Department of Defense on Thursday. Centers for Disease Control and Prevention Director Dr. Tom Frieden talked about the case at the National Press Club in Washington.
The woman went to a clinic in Pennsylvania, and a sample was forwarded to Walter Reed National Military Medical Center. Walter Reed found the bacteria in her urine. There is no indication of how the bacteria got into the woman's system. She had not traveled outside the United States within the past five months.
The CDC and the Pennsylvania Department of Health mobilized immediately to investigate the case and to trace contacts the patient may have had to see whether the bacteria had spread.
The woman was treated and released and has no other medical problems related to the bacteria that we know of, according to Dr. Alex Kallen, a medical officer with the CDC.
The unstoppable superbugs that could kill millions
In the United States,
over 350,000 cases of this sexually transmitted infection were reported in 2014, caused by the bacterium Neisseria gonorrhoeae. Resistance to antibiotics began to occur soon after their introduction in the 1930s and has continued to rise with resistance now seen against at least five of the drugs once used to treat it -- which include the commonly used antibiotics penicillin and tetracycline.
Hospitals are one of the main places superbugs are causing concern, as doctors are running out of viable options for antimicrobials. Leading the way are a group of bugs known as the ESKAPE pathogens, the first of which is Enterococcus faecium.This bacteria is commonly found in the intestines and female genital tract, but can sometimes cause infections. In some cases it has become
resistant to the vancomycin antibiotic used to treat infections and mostly in hospitals. Keeping hands clean is the main way to prevent transmission.
Staphylococcus aureus (staph) is a common type of bacteria which is often found on the skin, in nostrils and in the throat.
According to the CDC, one in three people carries it in their nose without being affected by it. It can cause mild infections of the skin, but if the bacteria gets into the bloodstream it hast the potential to become life threatening by poisoning blood.
Multidrug-resistant Staphylococcus aureus (MRSA) has been a concern for many years in hospitals. People with infected with this form of the bacteria are estimated to be
64% more likely to die than people with a non-resistant form of the infection.
Klebsiella bacteria have also developed a high level of resistance to antibiotics, such as
carbapenem. The bacteria naturally occurs in the intestines where it does not usually cause disease, but it can cause pneumonia, bloodstream infections and meningitis.
It's unlikely that healthy people are affected by the bacteria, but
patients in hospitals who use a ventilator, intravenous catheters or long courses of certain antibiotics are at higher risk of becoming infected.
Acinetobacter is a type of bacteria mostly found in soil and water. It can cause human disease, particularly in people with weakened immune systems or diabetes.
Outbreaks
usually happen in intensive care units and healthcare settings, with the bacteria becoming resistant to most commonly used antibiotics. Treatment has to be decided on a case-by-case basis.
Pseudomonas bacteria can be deadly for patients who are in critical care. According to CDC it's the cause of about
51,000 healthcare-associated infections in the United States each year. More than 6,000 of these cases are multi-drug resistant, leading to around 400 deaths per year. The most serious Pseudomonas infections usually occur in hospitals, affecting patients who are on breathing machines, using catheters or with wounds from surgery.
The bacteria Escherichia coli (E. coli) naturally occurs in your gut, and while most strains are harmless, some can cause severe foodborne diseases, with symptoms ranging from fever, nausea and vomiting to bloody diarrhea. The infections are transmitted by eating or drinking contaminated food and water.
Multi-drug resistance in E. coli has been
increasingly reported in urinary tract infections (UTIs). According to the WHO, the most widely used oral treatment -- fluoroquinolones -- are also becoming ineffective. A U.S woman was reported to be
infected with a rare kind of E. coli infection that is resistant to antibiotics, even one used as a last resort.
Influenza virus types A and B sweep through countries annually in the winter months; they cause fever, headaches and muscular pain in most cases, but also cause three to five million cases of severe illness and
250,000 to 500,000 deaths each year. The antiviral drugs oseltamivir and zanamivir are the main means of fighting infection. Preventative antivirals amantadine and rimantadine were once used to control seasonal spread, but high levels of resistance means their use is no longer recommended.
Resistance to zanamivir has also been reported. While the majority of viruses found globally are still sensitive to the key drugs, the resistant forms could easily spread as no other drug options remain available.
The CDC said it is looking for other potential cases in the health care facility the patient visited.
The bacteria have been identified in other infections outside the United States. Doctors saw cases in Europe, Canada and China.
The U.S. Department of Agriculture also found one strain of Colistin-resistant E. coli in a single sample of a pig intestine, according to a statement from the Department of Health and Human Services. The USDA is trying to determine what farm the pig came from to see whether any other animals were impacted.
These two cases are what the CDC characterized as a "warning sign, more than a catastrophe," according to Kallen.
The concern is that traits of this rare mutant Colistin-resistent E. coli could jump to other bacteria that respond only to Colistin, creating a potentially unstoppable superbug.
One report suggests that antibiotic-resistant infections can result in the deaths of half the patients who become infected.
Antibiotic resistance has become a growing problem in this country. The World Health Organization has warned that it is one of the biggest threats to global health today.
Frieden warned that although this is the first case in the United States, we should expect to see more such superbugs in the near future. Frieden, who often warns doctors against overuse of antibiotics, urged scientists to develop new drugs quickly.
Each year in the United States, at least 2 million people become infected with other kinds of bacteria that can't be beaten with most antibiotics, and at least 23,000 people die each year as a result of those infections, according to the CDC.
"The medicine cabinet is empty for some patients," Frieden said. "It is the end of the road unless we act urgently."
CNN's Elizabeth Cohen contributed to this report.