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A multiple antibiotic resistant strain of pseudomonas aeruginosa known as (Methicillin Resistant Pseudomonas Aeruginosa (MRPA) has forced the cancellation of some elective cardio thoracic and neurological surgery cases in the Royal North Shore (Australia).

Because of this outbreak, the intensive care unit remained closed this week until the bacteria is eliminated from the area.

The neurological surgery ward (6C) of the Intensive Care Unit within the hospital was closed prior to Easter and patients were moved to another section of intensive care while cleaning and sanitation of the area took place.

Environmental swabs are currently being tested for the suspect bacterium and the ward is expected to be re-opened this week once the area is confirmed free of this strain of bacterium.

MRPA was isolated and identified on 10 patients during the late March and this prompted the management of the hospital to take aggressive measures including isolating infected patients before closing the affected ward and basically bombing the area with super grade disinfectant.

Pseudomonas aeruginosa is commonly found in soil and water; however there are a few strains that have started to build up resistant against front line antibiotics. Once these strains multiply and become the dominant type within the environment, we have a real problem especially if patients using life-saving antibiotics are located in the same area.

According to a spokesperson within the hospital, they say that the hospital usually has about 30 to 40 cases of MRPA a year, mostly in intensive care wards.

Patients with confirmed MRPA were being cared for in isolation with treatment for their primary illness continuing without interruption. Their families were permitted to visit but had to follow infection control procedures such as washing hand before and leaving the hospital grounds.

Pseudomonas aeruginosa is a gram -ve rod shaped bacterium that is naturally found in many types of drinking water. According to European water regulations, it is a requirement to have Pseudomonas aeruginosa absent in a 250 ml sample of bottled water. Unfortunately no such regulation exists in the United States and other developed countries. Apparently, the Pseudomonas aeruginosa regulation in Europe originated as a quality control issue and not as a health effects issue.

Interestingly during the last 10 years, there have been an increase in the number of papers appearing indicating that Pseudomonas aeruginosa from drinking water is a health threat. This can only happen if the levels are high.

Being psychrotrophic, a food microbiologist will think it’s more a food spoilage issue than a health threat. The clinical microbiologist will think it is an opportunistic bacterium and can lead to a health threat. So where does this bacterium come from?

Pseudomonas aeruginosa is a ubiquitous environmental bacterium. It can be recovered, often in high numbers, in common food, especially vegetables. Moreover, it can be recovered in low numbers in drinking water. A small percentage of clones of Pseudomonas aeruginosa possess the required number of virulence factors to cause infection. As an opportunistic bacterium, Pseudomonas aeruginosa will not proliferate on normal tissue but requires previously damaged organs.

By further narrowing down the risk to human health, only certain specific hosts are at risk. They include patients with profound neutropenia, cystic fibrosis, severe burns, and those subject to foreign device installation. Other than these very well defined groups, the general population is normally immune to infection with Pseudomonas aeruginosa.

Although it is ubiquitous nature, there are ways to eliminate Pseudomonas aeruginosa from our food and drinking water. They include cooking foods properly, filtering or boiling drinking water.

If you are interesting in finding out the levels of Pseudomonmas aeruginosa in your water supply for food, I suggest you contact a reputable water microbiology laboratory.

Severe Infections Caused by Pseudomonas Aeruginosa. Perspectives on Critical Care Infectious Diseases, Band 7 Severe Infections Caused by Pseudomonas aeruginosa emphasizes controversies worldwide in the diagnosis, treatment, prevention and pathogenesis of pseudomonas aeruginosa infections. By including both chapters written by European authors and chapters written by North American experts, the reader is ensured of receiving a broad spectrum of opinions on controversial topics. Special attention is paid to such topics as the diagnosis of hospital-acquired pneumonia caused by p. aeruginosa, scheduled antibiotic therapy for patients with cystic fibrosis, empiric therapy for febrile neurotropenic patients, combination vs. single agent antibiotic therapy for severely ill patients, and alternatives to conventional antibiotic therapies. This excellent overview of our current understanding of pseudomonas aeruginosa pathogenesis will prove useful to clinicians and microbiologists around the globe. TOC:Contributors.- Preface.- Series Preface.- 1. Pseudomonas aeruginosa Infections in Specific Types of Patients and Clinical Set, Medical / Nursing ; infectious & contagious diseases ; medical microbiology & virology ; Infectious Diseases ; Microbiology, Severe Infections Caused by Pseudomonas Aeruginosa. Perspectives on Critical Care Infectious Diseases, Band 7

Have you ever questioned why pasteurized milk sometimes spoils before the best before code whilst being stored in the fridge? At the same time, it is accompanied by a slight rancid odor as well.

Interestingly it is caused by the presence of a group of bacteria that loves living in the cold environment; these are called psychrotrophs or psychrotrophic bacteria. Pseudomonas is one of the most common within the group and interestingly this is the same bacterium that causes spoilage (slimy layer) in raw chicken during refrigerated storage.

Did you know that even if you keep the milk chilled within the recommended storage temperature, a single cell of pseudomonas can multiply to over a million cells in the space of just six days? Even one of this bacterium in a carton of milk can cause a spoilage problem.

So how do these bacteria enter the milk even though the milk is pasteurized! Easily, it’s due to poor hygiene by the manufacturers because if it is pasteurized and packaged hygienically there should not be any spoilage bacterium present at all, nada!

The only bacterium that can survive the heating process is heat resistant bacteria such as bacillus species and these types will not grow at the refrigeration temperature. Hence there is not premature spoilage.