What are the superbugs?
Superbug or Enterobacteriaceae resistant to carbapenemase or CRE are bacteria that normally live in the intestine and is highly resistant to antibiotics.
The superbugs inherited names worthy of horror films like “killer bacteria” or nightmare bacteria for a good reason: the mortality rate associated with infection by superbugs (Enterobacteriaceae resistant or carbapenemase ERC) is more than 40% and even 50% according to the CDC (Centers for Disease Control and Prevention) in the United States.
Like most antibiotic resistant bacteria, they are found in healthcare settings. The population that stay away from hospitals has no reason to be afraid by superbugs.
Enterobacteriaceae resistant to carbapenemases or ERC have resistance mechanisms that may vary from superbug to another. The two categories of carbapenemase emerging in Enterobacteriaceae are enzymes KPC (Klebsiella pneumoniae producing carbapenemase) and NDM-1 (New- Delhi Metallo-beta-lactamase-1) recently responsible for many infections, particularly in the United Kingdom. The fact that the resistance genes of these bacteria were identified on plasmids is also a concern because this feature facilitates transmission of this resistance from to other bacterial species.
Causes of infection by superbugs
As already mentioned, the superbugs are bacteria from the bowel that have acquired antibiotic resistance mechanisms. Klebsiella and E. coli are examples of intestinal bacteria that can become resistant to antibiotics.The superbugs are sometimes found in other places such as the blood, wounds, lungs, urinary system or the meninges and then cause infections that are difficult to treat.
Powerful broad-spectrum antibiotics are used to treat infections caused by superbugs. When carbapenemens are too often used, bacteria develop resistance and become superbugs.
Transmission of superbugs
The superbugs are transmitted when the bacteria is transferred by contact of a patient infected or at another. For example, a nurse who forgot to wash her hands after she took care of a patient and who treat another patient with her contaminated hands. Transmission can also occur via a contaminated surface such as a poorly disinfected endoscopes. The US government recently issued warnings about this and patients at risk of recalls have been made in some US hospitals including UCLA in California.
The healthy patients have little risk of being infected but immunosuppressed patients or patients with catheter, or who are on ventilators are most at risk.
Symptoms of infection by superbugs
Symptoms of infection by superbugs vary depending on the infection site. It can be an urinary tract infection, or a respiratory infection or an infected wound that do not heal.
It can also be a carrier of the bacteria that is to say, have no symptoms and still be at risk of transmitting the infection to another patient.
The diagnosis of infection by superbugs
Physicians make the diagnosis of infection by superbugs taking a sample for a culture in a laboratory.
The treatment of superbugs
There are only a few antibiotics that can treat infections by superbugs, which is why they are so difficult to treat. For information, according to the US National Library of Medicine, only polymyxins, aminoglycosides, tigecycline, fosfomycin and temocillin are effective. Previously people used carbapenem antibiotics as last resort to treat gram-negative infections, now they have become useless.
The choice of the antibiotic should be based on the results of the culture. When an ERC bacteria grows the analysis is continued to verify its resistance to treatment options. Taking antibiotics too long after the healing process started could be a factor that promotes the growth of resistant Enterobacteriaceae to carbapenemases, that must be taken into account.
There are fewer and fewer new antibiotics, the reason is simple: the development of a new antibiotic costs millions if not billions of dollars, and when the antibiotic is on he market, medical authorities are quick to say that it should be used sparingly to not develop resistance. Then sales volume does not justify then investment. There is a new antibiotic to treat infections by resistant enterobacteria carbapenemases: the ceftazidime-avibactam from Actavis company. In December 2014, an advisory committee of the FDA (Food Drug Administration) recommended that the FDA approves the drug for the treatment of patients who have little or no choice of treatment for their infection.
According to the Public Health Department of North Dakota , a person who already have had an infection with a superbug could have another superbug infection in the furure.
The prevention of infections superbugs
One of the basic steps of prevention is the optimal use of antibiotics. The superbugs develop at the hospital because they are the places where antibiotics are the most used and the bacteria can transmit from a patient to another. Worse, is the resistance genes that can be passed from one bacterium to another. Thus two completely different bacteria e.g. Klebsiella and E. coli can exchange a gene resistant to antibiotics.
Another way to prevent infection is to ensure that medical equipment is cleaned carefully. For example, if endoscopes (these instruments which are introduced into the body to see, for example in the gut) areinadequately disinfected, they can be an important vector for transmission of superbugs.
As already mentioned, a recent reminder of the FDA has been done in the United States health care settings so that they ensure that the instruments are disinfected appropriately. It must be said that these devices have several tubes and they can be challenging to disinfect correctly. Two hospitals in California have already made recall patients who may have been contaminated. The Cedars-Sinai Medical Center is the second hospital in Los Angeles to conduct a recall after UCLA. We have to remember that an endoscope that is not desinfected correctly can also transmit many other diseases like hepatitis B and C and HIV.
The basic measures like hand washing are also a cornerstone of infection control in hospitals.
For patients victims of the superbugs returning home, the basic measures like hand washing are sufficient to prevent transmission.
Everyone can do their part by not harassing her doctor for an antibiotic prescription or following exactly doctor’s instructions when taking antibiotics. It is also important to complete treatment with antibiotics than not to take antibiotics for nothing. Partial treatment only select the most resistant bacteria.