Welcome to the Microbiology Information

This finding suggests suggests evolutionary biology and virology together can accelerate the discovery of viral-defence mechanisms, according to researchers at Fred Hutchinson Cancer Research Center.

These findings by Julie Kerns, Ph.D., a postdoctoral researcher in the Hutchinson Center’s Basic Science Division, published Jan. 25 in the open-access journal PLoS Genetics, present a striking example by which evolutionary studies can directly lead to biomedically important discoveries in the field of infectious diseases.

The immunity gene, called ZAP, is a key player in a newly discovered branch of antiviral defences in mammals referred to as ‘‘intrinsic immunity.’’ Host proteins like ZAP can target intracellular stages of the viral life cycle to inhibit viral activity. The ZAP gene, first discovered in rats, thwarts a variety of divergent viruses, from retroviruses (like HIV) to alphaviruses (like Sindbis) to filoviruses (like Ebola).

Researchers believe ZAP functions by virtue of its RNAbinding abilities, which recognize specific sequences of the virus and target their viral RNA for destruction. Host-virus interactions are a classic example of genetic conflict in which both entities try to gain an evolutionary advantage over the other. This ‘‘back-and-forth’’ evolution is predicted to result in rapid changes of both host and viral proteins, which
results in an evolutionary signature of positive selection, especially at the direct interaction interface.

“This suggests that we might be able to deduce host-virus conflicts purely by looking at rapidly evolving protein segments,” said Kerns, the lead author of the study, which was conducted in collaboration with senior author Harmit Singh Malik, Ph.D., of the Center’s Basic Sciences Division and also co-author Michael Emerman, Ph.D., of the Center’s Human Biology Division Department.

The researchers found that there has been very little sequence evolution in the RNA-binding domain, which
suggests that human ZAP may be similar to the rat gene in its viral RNA-binding specificity.

Surprisingly, the rapid evolution characteristic of “intrinsic immunity” genes was concentrated in a protein domain that was not even present in the originally discovered rat gene.

The authors found that humans encode two protein versions, or isoforms, from a single ZAP gene: a shorter version similar to the original rat gene and a longer version that possesses a rapidly evolving poly (ADP-ribose) polymerase (PARP)-like domain.

In virological assays, the longer human ZAP protein isoform has higher antiviral activity. Thus, positive selection correctly predicted the more potent antiviral isoform of this protein.

The authors further suggest that ZAP is locked in a conflict with alphaviruses. The discovery of a potential human gene that can restrict alphaviral infection is particularly timely as the mosquito-borne alphavirus, Chikungunya, was responsible for a large epidemic in parts of Southeast Asia in 2006 and is now threatening to invade certain parts of Europe.

The researchers believe that this finding has an enormous implications for the understanding of intrinsic immunity against viruses. This could potentially serve as a guide in the development of antiviral therapeutics.

“We think that a particular alphaviral protein may be playing an evolutionary ‘cat-and-mouse’ game with the ZAP gene,” Malik said. “Identifying this protein could lead to novel ways to tackle diseases caused by alphaviruses.”

Source http://www.fhcrc.org

Listeria appears again – but this time in sandwiches wwhere it was sold to 20 people at Middlemore Hospital in New Zealand.

These pre-packaged Thai chicken sandwiches were sold on Monday at the hospital’s Aviary Cafe, which is mainly used by staff.

The contamination was detected in routine listeria testing where the results were given to the hospital yesterday.

It was not known last night whether other sandwich varieties at the cafe were infected, or if other products from the sandwiches’ supplier, Naturezone, were infected with listeria and had been distributed to other outlets.

The bacterium can be fatal to people with low immune systems and can cause miscarriages or stillbirths if it infects pregnant women.

A spokeswoman for Spotless Services, the company that runs the cafe, said it was not yet known how many of its outlets had been stocked with the sandwiches. Naturezone could not be reached for comment last night.

Auckland Regional Public Health Service spokesman Dr Greg Simmons said last night that greatly improved methods of testing were bringing the listeria cases to the surface.

All positive tests in the past three weeks had come from the same testing facility.

“We are conducting a thorough site inspection at the company and we will ensure extensive product and environmental testing to identify the source,” Dr Simmons said

Despite the relatively low risk, he said, it was a serious situation.

“We are concerned that a whole lot of ready-to-eat products look like they are being contaminated. We would be silly not to be concerned.”

The bacterium usually produces fever, diarrhoea and general unwellness within three weeks of infection, although it can take as long as 10 weeks for symptoms to show.

Here is the draft policy (Sec. 555.320) for Listeria monocytogenes in Ready To Eat (RTE) Foods.

This draft guideline, when finalized, will represent the Food and Drug Administration’s (FDA’s) current thinking on this topic. It does not create or confer any rights for or on any person and does not operate to bind FDA or the public. You can use an alternative approach if the approach satisfies the requirements of the applicable statutes and regulations. If you want to discuss an alternative approach, contact the FDA staff responsible for implementing this guidance. If you cannot identify the appropriate FDA staff, call the appropriate telephone number listed on the title page of this guidance.

INTRODUCTION:
The purpose of this Compliance Policy Guide is to provide guidance to FDA Staff on FDA’s enforcement policy for Listeria monocytogenes (L. monocytogenes) in foods.

FDA’s guidance documents, including this guidance, do not establish legally enforceable responsibilities. Instead, guidances describe the Agency’s current thinking on a topic and should be viewed only as recommendations, unless specific regulatory or statutory requirements are cited. The use of the word should in Agency guidances means that something is suggested or recommended, but not required.

BACKGROUND:
L. monocytogenes is a pathogenic bacterium that is widespread in the environment and may be introduced into a food processing facility. L. monocytogenes can contaminate foods and cause a mild illness (called listerial gastroenteritis) or a severe, sometimes life-threatening, illness (called invasive listeriosis). Foods that have been implicated in outbreaks of invasive listeriosis have been foods that are ready-to-eat (RTE).

RTE foods can be contaminated if ingredients in the foods are contaminated with L. monocytogenes and are not treated to destroy viable cells of this pathogen, or if L. monocytogenes is allowed to contaminate the RTE food because of improper sanitary conditions or practices. Most RTE foods do not contain detectable numbers of L. monocytogenes. For many RTE foods, contamination with L. monocytogenes can be avoided – e.g., through the application of current good manufacturing practice requirements that establish controls on ingredients, listericidal processes, segregation of foods that have been cooked from those that have not, and sanitation. Sanitation controls include effective environmental monitoring programs designed to identify and eliminate L. monocytogenes in and on surfaces and areas in the plant.

In 2003, FDA and the Food Safety and Inspection Service of the United States Department of Agriculture, in consultation with the Centers for Disease Control and Prevention of the United States Department of Health and Human Services, released a quantitative assessment (the Risk Assessment) of relative risk associated with consumption of certain categories of RTE foods that had a history of contamination with L. monocytogenes, or that were implicated epidemiologically with an outbreak or a sporadic case of listeriosis. The Risk Assessment estimated that the risk of listeriosis would vary widely among these food categories.

According to the Risk Assessment, foods estimated to pose the highest risk of being associated with listeriosis are RTE foods that support the growth of L. monocytogenes. Examples of RTE foods that support the growth of L. monocytogenes include:

Milk;
High fat and other dairy products (e.g., butter and cream);
Soft unripened cheeses (greater than 50 percent moisture) (e.g., cottage cheese and ricotta cheese);
Cooked crustaceans (e.g., shrimp and crab);
Smoked seafood (e.g., smoked finfish and mollusks);
Raw seafood that will be consumed as sushi or sashimi;
Many vegetables (such as broccoli, cabbage, and salad greens);
Non-acidic fruit (such as melon, watermelon, and papaya); and
Some deli-type salads and sandwiches (particularly those containing seafood and those prepared at retail establishments without acidification and/or the addition of antimicrobial substances).

In contrast, the foods estimated to pose the lowest risk of being associated with listeriosis are foods that, because of intrinsic factors, extrinsic factors, and/or processing factors do not support the growth of L. monocytogenes. Intrinsic factors include chemical and physical factors that are normally within the structure of the food, e.g., pH and water activity. Extrinsic factors are those that refer to the environment surrounding the food, e.g., storage temperature. Processing factors include substances added to adjust the pH of food (e.g., acids) and substances that, alone or in combination with other substances, have antimicrobial properties (e.g., sorbates and benzoates). It is well established that L. monocytogenes does not grow when:

The pH of the food is less than or equal to 4.4;
The water activity of the food is less than or equal to 0.92; or
The food is frozen.

Foods may naturally have a pH or water activity that prevents growth of L. monocytogenes or processing factors may be deliberately used to achieve those characteristics (e.g., by adding acid to deli-type salads to bring the pH to less than or equal to 4.4). At pH values above 4.4, processing factors generally are used in combination to prevent the growth of L. monocytogenes (e.g., sorbates or benzoates may be used in combination with organic acids such as acetic acid, lactic acid, and citric acid in foods such as deli-type salads). The effectiveness of a particular listeristatic control measure in preventing growth in a particular RTE food generally is determined case-by-case, for example, using the results of growth studies specific to the food matrix.

Examples of RTE foods that generally are considered to not support the growth of L. monocytogenes include:

Fish that are preserved by techniques such as drying, pickling, and marinating;
Ice cream and other frozen dairy products;
Processed cheese (e.g., cheese foods, spreads, slices);
Cultured milk products (e.g., yogurt, sour cream, buttermilk);
Hard cheeses (less than 39 percent moisture) (e.g., cheddar, colby, and parmesan);
Some deli-type salads, particularly those processed to a pH less than 4.4 and those containing antimicrobial substances such as sorbic acid/sorbates or benzoic acid/benzoates under conditions of use documented to be effective in preventing the growth of L. monocytogenes;
Some vegetables (such as carrots); and
Crackers, dry breakfast cereals, and other dry foods.

Fruits, vegetables, and cheeses (e.g., soft and semi-soft cheeses) not listed in this CPG may include some products that support growth as well as other products that do not support growth.

POLICY:
FDA will review the available evidence on a case-by-case basis to determine if a food is a RTE food that supports growth or a RTE food that does not support growth.

Ready-to-Eat Food

“Ready-to-eat food” (RTE food) means a food that is customarily consumed without cooking by the consumer, or that reasonably appears to be suitable for consumption without cooking by the consumer.

A food may be considered to be suitable for consumption without cooking by the consumer, and thus a RTE food, even though cooking instructions are provided on the label. For examples, fresh and frozen crabmeat and individually quick frozen (IQF) peas and corn may be RTE foods. Some consumers eat such products without cooking, because they appear to be ready-to-eat.

Ready-to-Eat Foods that Support Growth of L. monocytogenes

Generally, we intend to consider that a RTE food will support the growth of L. monocytogenes if it does not meet the characteristics of a RTE food that does not support growth, as indicated in section III.C.

FDA may regard a RTE food that supports growth of L. monocytogenes to be adulterated within the meaning of section 402(a)(1) of the Federal Food, Drug, and Cosmetic Act (the Act; the FD&C Act) (21 U.S.C. 342(a)(1)) when L. monocytogenes is present in the food based on the detection method indicated in section IV.A.

Ready-to-Eat Foods that Do Not Support Growth of L. monocytogenes

A RTE food does not support the growth of L. monocytogenes if the food:
Has a pH that is less than or equal to 4.4; or
Is customarily held and consumed in a frozen state; or
Has a water activity that is less than 0.92; or
Is processed using an effective listeristatic control measure (e.g., an antimicrobial substance or a combination of factors such as pH, water activity, and antimicrobial substances).

FDA may regard a RTE food that does not support the growth of L. monocytogenes to be adulterated within the meaning of section 402(a)(1) of the Act (21 U.S.C. 342(a)(1)) when L. monocytogenes is present at or above 100 colony forming units per gram of food (cfu/g)

REGULATORY ACTION GUIDANCE:
Ready-to-Eat Foods that Support Growth of L. monocytogenes

The following represents criteria for recommending legal action to CFSAN/Office of Compliance/Division of Enforcement (HFS-605):
L. monocytogenes is detected in one or more subsamples of a RTE food that supports the growth of L. monocytogenes.

Use Bacteriological Analytical Manual Online, Chapter 10 – “Listeria monocytogenes,” “Detection and Enumeration of Listeria monocytogenes in Foods” as the method for detecting and confirming presence of L. monocytogenes (available at http://www.cfsan.fda.gov/~ebam/bam-10.html).

Ready-to-Eat Foods that Do Not Support Growth of L. monocytogenes

Consult with CFSAN/Office of Compliance/Division of Enforcement (HFS-605) before recommending legal action for RTE foods that do not support the growth of L. monocytogenes. Use ISO 11290-2:1998(E) “Microbiology of food and animal feeding stuffs – Horizontal method for the detection and enumeration of Listeria monocytogenes – Part 2: Enumeration method” as the method for enumerating L. monocytogenes. (ISO 11290-2:1998/Amd. 1:2004(E) “Microbiology of food and animal feeding stuffs – Horizontal method for the detection and enumeration of Listeria monocytogenes – Part 2: Enumeration method AMENDMENT 1: Modification of the enumeration medium” amends ISO 11290-2:1998(E). The amendment uses ALOA agar instead of PALCAM agar. If ALOA agar is not commercially available in the United States, use PALCAM according to ISO 11290-2:1998(E)). ISO methods are available from the International Organization for Standardization at http://www.iso.org/iso/en/ISOOnline.frontpage.

Use rapid biochemical test kits according to the Bacteriological Analytical Manual Online, Chapter 10 – “Detection and Enumeration of Listeria monocytogenes in Foods” Section E-11 (available at http://www.cfsan.fda.gov/~ebam/bam-10.html), instead of ISO 11290-2:1998(E) Section 9.5, for confirmation of L. monocytogenes isolates.

Foods that are Not RTE Foods
Consult with CFSAN/Office of Compliance/Division of Enforcement (HFS-605) when L. monocytogenes is present in a food that is not a RTE food.

Other Considerations

The criteria in this guidance do not establish an acceptable level of L. monocytogenes in food. FDA may choose to take legal action against adulterated food that does not meet the criteria for recommending legal action to CFSAN.

Further, the criteria in this guidance do not excuse violations of the requirement in section 402(a)(4) of the Act (21 U.S.C. 342(a)(4)) that food may not be prepared, packed, or held under insanitary conditions or the requirements in FDA’s good manufacturing practices regulation (21 CFR part 110). As set out in 21 CFR 110.80, food manufacturers must take “[a]ll reasonable precautions … to ensure that production procedures do not contribute contamination from any source.”

SPECIMEN CHARGES:
Domestic Seizure

The article of food was adulterated when introduced into and while in interstate commerce and is adulterated while held for sale after shipment in interstate commerce within the meaning of the Act, 21 U.S.C. 342(a)(1), in that it bears and contains a poisonous or deleterious substance, namely Listeria monocytogenes, which may render it injurious to health.

Import Detention
The article of food is subject to refusal of admission pursuant to section 801(a)(3) of the FD&C Act in that it appears to be adulterated within the meaning of section 402(a)(1) of the FD&C Act in that it bears and contains a poisonous or deleterious substance, Listeria monocytogenes, which may render it injurious to health.

Public health officials in the U.S. are investigating a major outbreak of listeria and have found up to 16 samples with the listeria bacteria at a milk processing plant.

The outbreak has resulted in the deaths of 3 elderly men who have died since June after drinking pasteurized milk that was contaminated with the bacteria.

The same strain of listeria also sickened a pregnant woman, who then miscarried and a second woman also was sickened after drinking milk from the plant.

The dairy processing plant in Shrewsbury is 35 miles west of Boston in Massachusetts, and is owned by Whittier Farms.

While officials have yet to determine exactly how the milk was contaminated, one environmental swab, one skim milk sample and seven flavored milk samples tested positive for the same strain of listeria that is now being blamed for the outbreak that sickened people.

The milk appears to have been contaminated during the production process and could have been lurking somewhere within the machinery. Experienced microbiologists are currently on site to determine the cause of the outbreak and to find potential reservoirs of the deadly micro-organisms.

So far, no further cases have been reported and health officials maintain that the health risk to the public is low.

The processing plant distributes milk under various brand names to stores across central Massachusetts and also operates a 500-acre farm in the town of Sutton.

Officials say the plant has been closed since December and will remain so while investigations continue and the bacterium is completely eradicated.

Here’s what they say on their site:

“Whittier Farms Inc. was notified today by the Department of Public Health that a press release would be issued today informing the public that Whittier Farms Inc. is being linked to cases involving listeria. Whittier Farms is fully cooperating with this investigation and will continue to do so.”

Listeriosis is a type of food poisoning that can be particularly dangerous to the elderly, infants, pregnant women and people with low immune system such as those chronic medical conditions; the symptoms include fever, abdominal cramps, headache, stiffness, nausea and diarrhea.

Researchers say they’ve found that people with atopic dermatitis i.e. eczema, are susceptible to bacterial infections in their skin because their bodies don’t produce enough of two antimicrobial peptides. The findings show that while an allergic reaction can cause a rash, true eczema is all about infection. And medicines containing or inducing the peptides could be used to fight the disorder, which affects millions worldwide.

Eczma patient Lack Natural Antibiotic in Skin
Researchers at National Jewish Medical and Research Center report in the October 10 issue of the New England Journal of Medicine that patients with atopic dermatitis, also known as eczema, are susceptible to bacterial infections of their skin because they fail to produce effective amounts of two antimicrobial peptides. The findings demonstrate for the first time the clinical significance of these peptides in humans, and suggest that a medication containing or inducing the peptides may one day be used to fight the infections that plague millions of atopic dermatitis patients. The accompanying editorial in the journal called it a “seminal study.”

“This study helps explain why 90 percent of atopic dermatitis patients are colonized by staphylococcus aureus and 30 percent develop active infections,” said the study’s senior author, Donald Leung, M.D., Ph.D., Head of Pediatric Allergy-Immunology at National Jewish Medical and Research Center, in Denver. “It is important to understand why people with this common skin disease are so susceptible to skin infections, especially in light of recent widespread concerns that they can develop severe infections after receiving a smallpox vaccination. Interestingly, these antimicrobial peptides are also needed to combat viral infections and therefore could account for the susceptibility of atopic dermatitis patients to eczema vaccinatum and herpes simplex infections.”

Atopic dermatitis is a common, chronic skin disease characterized by dry, itchy and easily irritated skin. It occurs most commonly in infants and young children, but can persist into adulthood. Severe cases can lead to sleep deprivation, chronic bacterial infections, and depression. Approximately one in nine people in the United States suffer from this disease at some point. Along with other allergic diseases, its prevalence has grown significantly in recent years.

Immunologists recently identified peptides in the skin that help fight incipient infections. They rarely appear in normal skin, but are produced in reaction to skin inflammation. Since atopic dermatitis patients are so frequently plagued by bacterial infections, Dr. Leung and his colleagues decided to investigate the potential role of the antimicrobial peptides in those patients.

They evaluated the levels of two antimicrobial peptides, known as LL-37 and HBD-2, in eight patients with moderate to severe atopic dermatitis, 11 psoriasis patients, and six healthy individuals. Psoriasis is an inflammatory skin disease, whose patients rarely suffer skin infections. Microscopic examination of skin samples showed significant amounts of the peptides in the skin of psoriasis patients, but none to minor amounts in skin from atopic dermatitis patients, and none in the skin of healthy controls. Additional analysis indicated that most psoriasis patients had at least 10 times as much of the peptides in their skin as did atopic dermatitis patients. Many atopic dermatitis patients had no detectable amounts of the antimicrobial peptides in their skin.

When the researchers treated staphylococcus aureus colonies with the antimicrobial peptides, levels found in skin of psoriasis patients killed the bacteria. The researchers also found that two hormone-like proteins associated with the immune response and commonly secreted by atopic dermatitis patients’ cells, IL-4 and IL-13, suppressed the production of HBD-2 in cell cultures.

“These findings indicate that atopic dermatitis patients have an impaired immune response that prevents them from producing adequate amounts of antimicrobial peptides in their skin,” said Dr. Leung.

The research suggests that the missing peptides might one day be used as a treatment to prevent skin infections in atopic dermatitis patients.

“Our body normally makes these peptides to fight infections, so there might be fewer side effects than with conventional antibiotics,” said co-author Richard Gallo, M.D., Ph.D., Chief of Dermatology at the Veterans Affairs San Diego Healthcare System and Associate Professor of Medicine at the University of California, San Diego. In 1994, Dr. Gallo was the first to discover the antimicrobial peptides in mammalian skin. The peptides might have another advantage over conventional antibiotics, said Dr. Gallo. While conventional antibiotics attack only bacteria, the antimicrobial peptides fight bacteria, viruses and fungi.

Researchers will also be working in the next several years to alter the immune response of atopic dermatitis patients to promote the production of the antimicrobial peptides, said Dr. Leung.

The findings could shed light on atopic dermatitis patients’ susceptibility to eczema vaccinatum, a widespread skin infection that can afflict those who receive the smallpox vaccination. They may have relevance for other diseases, as well. For instance, it is known that tuberculosis and leprosy patients, whose cells secrete the same immune system regulators as atopic dermatitis patients, are more likely to have disease that spreads widely in their bodies.

The intriguing possibility that a virus which causes cancer in mice could also spread in humans has been raised by laboratory scientists……. again

The Austrian-led team found that mouse mammary tumour virus (MMTV) – which causes breast cancer in the animals – could replicate in human cells.

Other cancer experts, however, said the results, in the journal Retrovirology, should be treated with caution.

They said there was little evidence to link it to human breast cancer.

Viruses are now known to be involved in the development of several cancers – including cervical and liver cancer.

MMTV was discovered in the 1930s, and has been previously suggested as a possible cause of human breast cancer.

However, even though traces of the virus have been found before in human breast cancer cells, attempts to prove a link have foundered in the past because no-one could find evidence that the virus could survive and replicate in that environment.

The latest research claims to have done this – they say MMTV ‘rapidly spreads’ in breast cancer cells in their laboratory.
Dr Stanislave Indik, who led the team, said: “Often, viruses infect cells but cannot replicate further.
“If they can replicate, the chances that they cause disease may be increased.”

The researchers said that while not proving that the virus can cause breast cancer in real people, it “lends more weight” to theories linking the virus to the disease, and to other conditions such as the liver disease primary biliary cirrhosis.

They said that if the MMTV were to be proven, existing drugs such as the anti-HIV medication AZT would stop it replicating.

Other experts are no so convinced that MMTV is likely to be a culprit for the disease.

Epidemiologist Dr Rob Newton, from the charity Cancer Research UK, said: “This paper suggests that, under controlled laboratory conditions, a mouse virus can infect cultured cells derived from human breast tissue.
“It does not demonstrate that this actually happens in the real world, nor have the researchers shown that such infection leads to the development of cancer.

“At the present time, the overall evidence in this area does not support the view that MMTV is a cause of human breast cancer.”

This was echoed by Dr Sarah Cant, from Breakthrough Breast Cancer, who said: “Although this research indicates the mouse mammary tumour virus can spread between breast cancer cells in the lab, there is still no concrete scientific evidence that the virus causes breast cancer in humans.

“Much more research would be needed before we can say whether or not MMTV can be passed from mice to humans to cause breast cancer.”

Peptides previously isolated from hybrid striped bass may be able to control certain viral diseases in fish and humans, suggests new research published in the journal Virology. ”The peptides were highly inhibitory to channel catfish virus, as well as certain amphibian viruses,” said Ed Noga, a co-investigator and North Carolina Sea Grant researcher. The study was led by Greg Chinchar of the University of Mississippi Medical Center.

Peptides Antibiotics From Fish May Fight Viral Diseases, Sea Grant StudyFinds
Peptides previously isolated from hybrid striped bass may be able to control certain viral diseases in fish and humans, suggests new research published in the journal Virology. ”The peptides were highly inhibitory to channel catfish virus, as well as certain amphibian viruses,” said Ed Noga, a co-investigator and North Carolina Sea Grant researcher. The study was led by Greg Chinchar of the University of Mississippi Medical Center.

The peptide antibiotics or ”piscidins,” a name derived from pisces, the Latin word for fish, originally were isolated from mast cells — found in the immune systems of fish and other vertebrates, including humans. ”The results suggest that piscidins may be an important defense for fish against viral infections, which are among the most serious diseases in aquaculture,” added Noga. ”They also have the potential to fight viral infections in humans, particularly the herpes viruses.” Earlier work by other researchers found that viruses can be sensitive to other types of antimicrobial peptides besides piscidins, according to Noga. With the spread of emerging infectious diseases and the growing problem of antibiotic resistance, the search for effective treatments has taken on greater urgency.

In a previous North Carolina Sea Grant study, researchers found that piscidins possessed potent broad-spectrum antibacterial activity, including the ability to fight fish and human pathogens resistant to other antibiotics. This was the first time that researchers had isolated a peptide antibiotic from mast cells of any animals. ”The next step is to determine the specific role that piscidins play in defending fish against viral infections, as well as finding out if piscidins can effectively treat viral disease in an animal model,” Noga said. The study was funded by North Carolina Sea Grant, the National Science Foundation, and the U.S. Department of Agriculture.

Here is a load of crap, pajamas that is designed to protect against MRSA by incorporating silver into its fabric at a level of 2%.

They claim that by having 2% silver woven into its fabric, it can protect against the hospital super bug MRSA. It has already gone on sale UK with M&S the first British retailer to stock the £45 Sleep Safe pajamas and is trialing them at 100 stores.

Silver is known for its infection-fighting properties and silver-laced nightwear has already been tested in a handful of hospitals.

But campaigners called the pajamas a gimmick and said the only way to tackle MRSA was by making hospitals cleaner.

MRSA

MRSA (methicillin resistant Staphylococcus aureus) is a bacterium that can live completely harmlessly on the skin of healthy people but can lead to serious infection.

MRSA infections can cause a broad range of symptoms depending on the part of the body that is infected. These may include surgical wounds, burns, catheter sites, eye, skin and blood.

Dr Mark Enright, a microbiologist at Imperial College London, said that the pajamas would reduce the risk of a patient getting a skin infection that enters a wound.

The problem lies within the hospitals. They are dirty and it should not be up to the public to safeguard themselves

Tony Kitchen of MRSA Support

A spokesman for M&S said: “The fabric that the pajamas are made of has been clinically proven to reduce the risk of MRSA by killing bacteria that come into contact with the fabric.

“Clinical trials are currently ongoing and are three quarters of the way through. The interim results were positive.”

They are only available for men at present and are produced using a fabric which 2% silver has woven into it.

Katherine Murphy, from the Patients’ Association, said: “We welcome the fact these are going on sale, but it shows how desperate the public is.”

However, Tony Kitchen of MRSA Support said: “It sounds like a gimmick – it cannot be a super suit and probably doesn’t make a jot of difference.

“The problem lies within the hospitals. They are dirty and it should not be up to the public to safeguard themselves, it’s the ethos of the hospital that needs to change.”

A spokesman added that if the pajamas did prove effective then they ought to be provided by the health service. rather than paid for by the patient.

An eight hour listeria test is what DuPont Qualicon has just annouced.

The new test is genetic-based and allows food companies to detect Listeria on environmental surfaces in only eight hours.

A spokes person for DuPont Qualicon says the new assay “is the first commercial application of Reverse-Transcriptase PCR for bacterial testing in food.” It is part of a suite of BAX(R) system products.

“This flexible test can give food companies clear, precise results at the end of a shift,” said Kevin Huttman, president of DuPont Qualicon. “With fast, accurate detection of Listeria, even at low concentrations, food processors get the information they need to take action sooner and release product faster.”

Listeria is found in many kinds of foods and us usually killed with proper cooking. Ready-to-eat products, such as hot dogs and deli meat, can become contaminated between cooking and packaging, however. The infection Listeriosis is caused by eating food contaminated with pathogenic Listeria monocytogenes. This illness is especially risky for pregnant women and immuno-compromised individuals. DuPont Qualicon said.

Applications

The BAX® system detects all species of Listeria, even at very low concentrations (101 cfu/mL).

With reverse-transcriptase PCR, samples do not require the usual 24-48 hour enrichment in nutrient brotoh. Instead, Listeria cells are resuscitated by heating in the collection buffer solution for four hours, providing a jump-start to the process.

Validation studies on stainless steel using both the classic and Q7 models have shown that the BAX® system detected more positive results on spiked samples than the reference USDA FSIS culture method. In a panel of 58 strains across 7 species of Listeria and 52 strains of non-Listeria, the assay demonstrated 100% inclusivity/exclusivity.

Approvals

The BAX® system 8-hour Listeria assay will be submitted to AOAC-RI for Performance Tested Method approval.

Source

Streptococcus throat has become harder to fight using penicillin or amoxicillin, but that’s not because the Streptococci have developed a resistance to those drugs. Instead, more than 50 percent of children have bacteria in their throats that protect strep germs.

New versions of antibiotics called cephalosporins are targeting the other bacteria, improving the odds of successful treatment fivefold.

Strep throat is the second-most-common reason children get antibiotics. But the gold standard antibiotics they get don’t always clear up the infection.

Pediatric infectious disease specialist Michael Pichichero, of the University of Rochester Medical Center in New York, says, says the standard strep drugs — amoxicillin and penicillin — fail in about 25 percent of kids.

“Strep is not actually resistant to penicillin or amoxicillin so, that cannot explain the failures that we’re seeing,” he says.

Instead, other bacteria are the problem. More than half of kids have bacteria in their throats that protect strep germs.

Dr. Pichichero says, “This is very much different from 20 or 30 years ago where almost all children treated with penicillin and amoxicillin would be cured.”

But his research shows newer drugs can kill strep. One in four kids fails treatment with penicillin. One in six fails newer drugs called cephalosporins. Only one in 20 fail the newer versions of those drugs. The newer antibiotics only need to be taken for four to five days, rather than the 10-day course of the older drugs.

BACKGROUND:
Researchers at the University of Rochester Medical Center have found that a short treatment of a newer class of antibiotics is more effective than the traditional 10-day dose of older antibiotics like penicillin and amoxicillin to treat strep throat. The Rochester scientists reviewed over 47 studies over the past 35 years involving more than 11,000 children and found that 25 percent of children treated for strep throat with penicillin ended up back in the doctor’s office within three weeks.

HOW ANTIBIOTICS WORK:
Infections are caused by single-celled organisms called bacteria, which can sometimes evade the body’s immune system and begin reproducing.

Antibiotics kill those harmful bacteria in various ways, such as preventing a bacterium from turning glucose into energy, or preventing it from construct a cell wall. The bacteria die instead of reproducing. Antibiotics are like selective poisons, because they target bacteria and not the body’s own cells.

They are not effective against viruses, however. Unlike bacteria, a virus isn’t a living, reproducing lifeform, just a piece of DBA or RNA. A virus injects its DNA into a living cell and the cell itself reproduces more of the viral DNA. There is nothing to “kill,” so antibiotics don’t work on viruses.

ABOUT STREP THROAT:
Most sore throats are caused by viruses and generally clear up without medical treatment.

Strep throat is an infection caused by a type of bacteria, and thus needs treatment with antibiotics. Symptoms include fever, stomach pain and red swollen tonsils. The bacteria can be transferred to others by sneezing, coughing or shaking hands.

A doctor will usually take a throat culture to test for strep throat. Lack of treatment can lead to other health problems, such as rheumatic fever (which can damage the heart), scarlet fever, blood infections or kidney disease.

DRUG RESISTANCE:
Bacteria are highly adaptive, and over time they naturally develop resistance, protecting them from incoming germs (and antibiotics) and making them harder to kill.

Repeated exposure to penicillin and amoxicillin can result in a throat full of bacteria that can shield strep germs from the older drugs.

The surviving bacteria then reproduce more and become more dominant. Sometimes parents discontinue antibiotic medication prematurely when their children begin to feel better, so the strep germ isn’t entirely killed off, leading to much more severe infections requiring the use of even stronger drugs later on.