MRSA News

Zero target for infections to encourage under reporting?

Mon, 21 Sep 2009 15:19 GMT

Nosocomial infections represent a serious public health problem. Some recent studies, most of which used strong educational programs, showed a dramatic decrease in the rates of nosocomial infections, particularly catheter-related infections in the intensive care unit. Thus, the concept of “zero risk” is flourishing in the recent literature, and some insurance networks have decided to limit reimbursement for treatment of some of the health care-associated infections, on the grounds that most of them are preventable. This viewpoint article emphasizes the risk of such a position and enumerates the reasons why such a philosophy could be counterproductive. In particular, this philosophy does not fit with the concept of self-declaration of severe adverse events and could push clinicians to underreport those events.

via The “zero risk” concept for hospital-acquired infe…[Clin Infect Dis. 2009] – PubMed Result.

Cuyahoga County Jail under MRSA pressure

Mon, 07 Sep 2009 02:09 GMT

The health department has recommended that the Cuyahoga County Jail take steps to reduce the spread of drug-resistant staph infections among inmates. The number of confirmed cases at the jail has risen from 63 in 2005 to 173 last year. The jail had reported 66 cases as of Aug. 18 — a pace that would total 106 cases by the end of the year, said Matt Carroll, director of the Cleveland Department of Public Health. While the projected total would be a decline from last year, the department wants to monitor the situation more closely and has asked the jail to provide monthly reports.

via Cuyahoga County Jail urged by health department to take steps to reduce spread of drug-resistant staph infections – cleveland.com.

How manuka honey helps fight infection

Mon, 07 Sep 2009 02:07 GMT

Manuka honey may kill bacteria by destroying key bacterial proteins. Dr Rowena Jenkins and colleagues from the University of Wales Institute – Cardiff investigated the mechanisms of manuka honey action and found that its anti-bacterial properties were not due solely to the sugars present in the honey. The work was presented this week 7-10 September, at the Society for General Microbiology's meeting at Heriot-Watt University, Edinburgh.Meticillin resistant Staphylococcus aureus MRSA was grown in the laboratory and treated with and without manuka honey for four hours. The experiment was repeated with sugar syrup to determine if the effects seen were due to sugar content in honey alone. The bacterial cells were then broken and the proteins isolated and separated on a system that displayed each protein as an individual spot. Many fewer proteins were seen from the manuka honey-treated MRSA cells and one particular protein, FabI, seemed to be completely missing. FabI is a protein that is needed for fatty acid biosynthesis. This essential process supplies the bacteria with precursors for important cellular components such as lipopolysaccarides and its cell wall. The absence of these proteins in honey-treated cells could help explain the mode of action of manuka honey in killing MRSA.

via How manuka honey helps fight infection.

Special dyes could make fabric an MRSA killer

Sat, 05 Sep 2009 09:41 GMT

The mordant-dyed non-mercerized knitted cotton samples adsorb larger amounts of copper ions directly bound to cotton during pre-mordanting. The ability of the copper ions bound to cotton and to the dye during pre- or post-mordanting is higher than that of the copper ions contained in the dye molecule. In addition, mordant-dyed cotton fabrics exhibited antibacterial activity against Staphylococcus aureus and MRSA, and thus had potential as deodorizing/antibacterial fabrics.

via Deodorizing and Antibacterial Abilities by Knitted Cotton Fabrics Mordant Dyed With Reactive Dyes and Copper (ii) Sulfate — Kobayashi et al., 10.1177/0040517509342313 — Textile Research Journal.

MRSA a factor in some swine flu deaths in kids

Fri, 04 Sep 2009 10:17 GMT

* Three of the 23 children tested had MRSA (multi-drug-resistant staph) infections.

Frieden noted that seasonal flu is just as deadly to children as is swine flu, and stressed the importance of kids getting seasonal flu vaccines.

He also noted that until H1N1 swine flu vaccine becomes available in mid-October — and until that vaccine has time to produce immunity to swine flu — parents should limit the spread of flu by keeping their kids home when they are sick and by teaching all children to wash their hands frequently and observe cough/sneeze etiquette.

via New Details on Swine Flu Deaths in Kids.

For CA-MRSA, how much PVL is too much?

Fri, 04 Sep 2009 01:26 GMT

Panton-Valentine leukocidin (PVL) is a cytolytic toxin, and its genes are encoded on a S. aureus bacteriophage integrated into the bacterial genome. PVL may be the key toxin responsible for enhanced virulence of community-associated methicillin-resistant S. aureus (CA-MRSA), but this is controversial. In many bacteria, expression of toxin genes encoded on such phage are induced under stress, including antibiotics. In this issue, Wirtz et al. prove that phage induction increases expression of PV-luk mRNA dramatically. But suprisingly, they show that the clone responsible for most CA-MRSA infections in the USA have defective phage and fail to overexpress the toxin.

via For CA-MRSA, how much PVL is too much? — Lindsay, 10.1099/mic.0.034041-0 — Microbiology.

Antibiotics – over the counter sales a bad trend

Thu, 03 Sep 2009 02:33 GMT

Antibiotics are overused across the world by prescription, self-medication or over the counter (OTC) availability. In the UK, the agenda to increase patient choice has stimulated a move towards greater availability of OTC antibiotics. This trend needs to be urgently reviewed and controlled. The Medicines and Healthcare products Regulatory Agency is currently reviewing applications for reclassification of trimethoprim and nitrofurantoin from prescription-only medicines to pharmacy availability or OTC. It is important that anti-infectives do not become more freely available. With the quantity of antibiotic use linked to antibiotic resistance, Society should seek to preserve the use of this irreplaceable resource by education and regulation.

via Antibiotic stewardship–more education and regulation not more availability? — Dryden et al., 10.1093/jac/dkp305 — Journal of Antimicrobial Chemotherapy.

Door handle firm using anti-bacterial coating

Wed, 02 Sep 2009 23:53 GMT

A LEADING manufacturer of door handles is helping businesses, schools and hospitals fight the threat of swine flu with its anti-bacterial coating service. Dortrend International is based in Stourport-on-Severn and is the only UK distributor of TouchClean. The anti-bacterial coating has the technology and components to kill and stop the spread of the swine flu virus on surfaces, walls and equipment.

via Door handle firm using anti-bacterial coating (From Berrows Journal).

FDA Issues Warning Letter to Johnson & Johnson over MRSA drug

Wed, 02 Sep 2009 23:47 GMT

As of 2003, MRSA made up 60% of hospital S. aureus infections in the USA, so effective means to treat it are highly prized. Analysts predicated J&J could make nearly $500 million from ceftobiprole in 2010 alone, but now the drug may have to wait a long time before it is approved for sale.

The FDA’s investigation of the trial revealed that it had not been properly monitored, nor had thorough records been kept. Despite ascertains that the drug would be administered in a controlled environment, it was found that some patients had been self-medicating in their homes, which had also resulted in improper storage of the drug. The study was also found to have been improperly blinded, with the doses being prepared by the nurses who administered them and cared for the patients rather than a pharmacist who would be unaware of who was receiving the drug and the placebo. More seriously, the administration of the drugs was sometimes delayed, which could have resulted in the primary infection getting worse, or even the onset of sepsis and death. As well as responding to these concerns, the FDA letter asked J&J to establish procedures in any ongoing or future trials to make sure these mistakes are not repeated.

via The Lancet Student » Archive » FDA Issues Warning Letter to Johnson & Johnson.

Pfizer fined $2.3 billion over Linezolid marketing

Wed, 02 Sep 2009 23:43 GMT

Pfizer Inc. ignored a 2005 FDA Warning Letter to stop promoting its antibiotic Zyvox(R) as clinically superior to the significantly less expensive, generic vancomycin when its own FDA-approved label indicated otherwise. The drug giant also defrauded federal and state taxpayers by marketing Zyvox off-label, according to a qui tam whistleblower complaint filed by Philadelphia law firm Sheller, P.C. and other documents unsealed with today's $2.3 billion Pfizer settlement.

The $2.3 billion settlement included off-label marketing allegations for the withdrawn arthritis drug Bextra(R), which was included in the Sheller complaint. Zyvox (linezolid) is an antibacterial agent that is approved by the FDA to treat certain types of infections, including nosocomial pneumonia and complicated skin and skin structure infections (“CSSSIs”) due to Methicillin Resistant Staphylococcus Aureus (“MRSA”). Worldwide sales of Zyvox totaled $1.115 billion in 2008.

The largest pharmaceutical qui tam whistleblower settlement in history, the $2.3 billion settlement was announced today by the U.S. Department of Justice and the U.S. Attorney's Office for the District of Massachusetts.

via Sheller, P.C. Law Firm Instrumental in Pfizer's $2.3 Billion Settlement Today in Largest Pharmaceutical Whistleblower Case in History.

Drug Resistance Genes – always one waiting in the wings (or on your skin)

Wed, 02 Sep 2009 13:56 GMT

To understand the process by which antibiotic resistance genes are acquired by human pathogens, we functionally characterized the resistance reservoir in the microbial flora of healthy individuals. Most of the resistance genes we identified using culture-independent sampling have not been previously identified and are evolutionarily distant from known resistance genes. By contrast, nearly half of the resistance genes we identified in cultured aerobic gut isolates (a small subset of the gut microbiome) are identical to resistance genes harbored by major pathogens. The immense diversity of resistance genes in the human microbiome could contribute to future emergence of antibiotic resistance in human pathogens.

via Functional Characterization of the Antibiotic Resistance Reservoir in the Human Microflora — Sommer et al. 325 (5944): 1128 — Science.

Different MRSA strains for Different folks

Wed, 02 Sep 2009 13:46 GMT

Approximately one-third of the human population is asymptomatically colonized by Staphylococcus aureus. However, much of the global diversity within the carriage populations remains uncharacterized, and it is unclear to what degree the variation is geographically partitioned. We isolated 300 carriage isolates from 1,531 adults contemporaneously in four countries: France, Algeria, Moldova, and Cambodia. All strains were characterized by multilocus sequence typing. Six clonal complexes (CCs) were present in all four samples (CC30, -45, -121, -15, -5, and -8). Analyses based on the genotype frequencies revealed the French and Algerian samples to be most similar and the Cambodian sample to be most distinct. While this pattern is consistent with likely rates of human migration and geographic distance, stochastic clonal expansion also contributes to regional differences. Phylogenetic analysis revealed a highly divergent and uncharacterized genotype (ST1223) within Cambodia. This lineage is related to CC75, which has previously been observed only in remote aboriginal populations in northern Australia.

via Comparisons between Geographically Diverse Samples of Carried Staphylococcus aureus — Ruimy et al. 191 (18): 5577 — The Journal of Bacteriology.

Optical Mapping will aid MRSA analysis

Wed, 02 Sep 2009 13:43 GMT

Staphylococcus aureus is a highly versatile and evolving bacterium of great clinical importance. S. aureus can evolve by acquiring single nucleotide polymorphisms and mobile genetic elements and by recombination events. Identification and location of novel genomic elements in a bacterial genome are not straightforward, unless the whole genome is sequenced. Optical mapping is a new tool that creates a high-resolution, in situ ordered restriction map of a bacterial genome. These maps can be used to determine genomic organization and perform comparative genomics to identify genomic rearrangements, such as insertions, deletions, duplications, and inversions, compared to an in silico (virtual) restriction map of a known genome sequence. Using this technology, we report here the identification, approximate location, and characterization of a genetic inversion of ~500 kb of a DNA element between the NRS387 (USA800) and FPR3757 (USA300) strains. The presence of the inversion and location of its junction sites were confirmed by site-specific PCR and sequencing. At both the left and right junction sites in NRS387, an IS1181 element and a 73-bp sequence were identified as inverted repeats, which could explain the possible mechanism of the inversion event.

via Optical Mapping Reveals a Large Genetic Inversion between Two Methicillin-Resistant Staphylococcus aureus Strains — Shukla et al. 191 (18): 5717 — The Journal of Bacteriology.

Antibiotics for Emerging Pathogens

Wed, 02 Sep 2009 13:37 GMT

Antibiotic-resistant strains of pathogenic bacteria are increasingly prevalent in hospitals and the community. New antibiotics are needed to combat these bacterial pathogens, but progress in developing them has been slow. Historically, most antibiotics have come from a small set of molecular scaffolds whose functional lifetimes have been extended by generations of synthetic tailoring. The emergence of multidrug resistance among the latest generation of pathogens suggests that the discovery of new scaffolds should be a priority. Promising approaches to scaffold discovery are emerging; they include mining underexplored microbial niches for natural products, designing screens that avoid rediscovering old scaffolds, and repurposing libraries of synthetic molecules for use as antibiotics.

via Antibiotics for Emerging Pathogens — Fischbach and Walsh 325 (5944): 1089 — Science.

How community MRSA enters a district

Wed, 02 Sep 2009 13:32 GMT

Results: The S. aureus population consisted of 13 clonal complexes and two Singleton lineages together with 56 sporadic isolates. Five lineages contained MRSA; however, these were not the predominant methicillin-susceptible S. aureus (MSSA) lineages. There was greater diversity amongst the MSSA while the MRSA appeared to have emerged clonally following acquisition of the staphylococcal cassette chromosome mec. Three MRSA lineages were considered to have been endemic in the communities and have subsequently become predominant lineages of CA-MRSA in the wider WA community. People colonized with MSSA tended to harbour clones of a different genetic lineage at each anatomical site while people colonized with MRSA tended to harbour clones of the same lineage at each site. Overall, the isolates were resistant to few antimicrobials.

Conclusions: Although the evidence suggests that in WA CA-MRSA strains arose in remote communities and have now disseminated into the wider community, there is no evidence that they arose from the predominant MSSA clones in these communities.

via Population dynamics of methicillin-susceptible and -resistant Staphylococcus aureus in remote communities — O'Brien et al., 10.1093/jac/dkp285 — Journal of Antimicrobial Chemotherapy.

Rise of resistant strains means faster testing needed

Wed, 02 Sep 2009 13:24 GMT

An expanding population of bacterial strains that are drug resistant, including methicillin-resistant Staphylococcus aureus MRSA, will be the most important justification for nucleic acid-based tests NAT. According to “Infectious Disease Diagnostic Markets,” a new report from leading life science market research company Kalorama Information, the most substantial growth in the $8.4 billion market for infectious disease diagnostics is in molecular testing.The needs of infectious disease testing are such that the two traditional methods, culture-based assays and immunoassays, are becoming increasingly inadequate. One key reason for this is the increase in drug-resistant infections. Immunoassays have no analytical potential here and culture-based assays for bacterial susceptibility/sensitivity, though low cost, are slow and often difficult.”Relevancy is established through significantly improved efficacy and not marginal improvement,” says Bruce Carlson, publisher of Kalorama Information. “NAT testing can be put to many uses, but what will get it into more labs is its role in determining the genetic differences that make a bacterial strain such as MRSA or MDR-TB/XDR-TB drug resistant, with results in 2-4 hours.”

via In Drug Resistant Strains, a Raison d'Etre for NAT Testing.

Storytelling: its place in infection control education

Wed, 02 Sep 2009 02:01 GMT

It is generally accepted that hand hygiene is the single most effective measure to prevent health care associated infection. Similarly, education is thought to be the cornerstone of effective practice. While common sense supports the notion that hand hygiene compliance would be enhanced by producing a well informed health care worker, traditional didactic methods of teaching are often poor at invoking and sustaining behaviour change. Storytelling is gaining popularity as an educational activity as it is said to stimulate thought, reflection and enhance the learning experience. This paper, describes one way in which storytelling may be used within a hand hygiene improvement strategy.

via Storytelling: its place in infection control education — Cole 10 (5): 154 — Journal of Infection Prevention.

Swiss study highlights new genetic shifts in MRSA infection

Wed, 02 Sep 2009 01:53 GMT

The study periods of this survey identified 292 S. aureus isolates causing BSI. Extensive molecular characterization, including genotyping as well as toxin, agr, and staphylococcal cassette chromosome content determinations, allowed us to describe epidemiological evolution in comparison to that discussed in our previous study. Our main epidemiological observation shows that the incidence of BSI remained constant but that methicillin (meticillin)-resistant S. aureus strains with a wider variety of genetic backgrounds now harbor pyl, as has already been reported in different European countries. We noticed stable numbers of BSI episodes involving community-acquired methicillin-sensitive S. aureus (MSSA), whereas a drastic increase in the number of strains harboring the tst gene was recorded. The increase in the number of tst gene-harboring strains is related to known hospital-acquired MSSA isolates and appears related to epidemic episodes in specific HCIs. Monitoring the increase in prevalence of specific strains helps us understand where the standard precautions are not satisfactorily applied or do not efficiently prevent the spread of epidemic MSSA strains in these HCIs. The recent increases in incidence of these strains call for particular vigilance to avoid the spread of potentially virulent MSSA strains harboring the tst gene and for continuance of this strategy of BSI surveillance.

via Variable-Number Tandem Repeat Analysis and Multilocus Sequence Typing Data Confirm the Epidemiological Changes Observed with Staphylococcus aureus Strains Isolated from Bloodstream Infections — van der Mee-Marquet et al. 47 (9): 2863 — Journal of Clinical Microbiology.

CA MRSA spreads in Nigeria

Wed, 02 Sep 2009 01:49 GMT

The methicillin-susceptible S. aureus strains (ST1, ST5, ST15, ST7, ST8, ST25, ST30, ST72, ST80, ST121, and ST508) were heterogeneous by phenotypic and genotypic analyses. The first report of a Panton-Valentine leukocidin-positive ST88 strain (agr III, SCCmec IV) in Nigeria, as well as genetic analyses of this strain, is presented in this study. The ST88 strain was resistant to trimethoprim-sulfamethoxazole as well as to penicillin and oxacillin. CA-MRSA infections are increasing rapidly among young patients with ophthalmologic and auricular infections. Urban regions with populations of lower socioeconomic status and evidence of overcrowding appear to be at high risk for the emergence of this clone.

via Emergence of a Community-Associated Methicillin-Resistant Staphylococcus aureus Strain with a Unique Resistance Profile in Southwest Nigeria — Ghebremedhin et al. 47 (9): 2975 — Journal of Clinical Microbiology.

Nigeria sees PVL MRSA emerging

Wed, 02 Sep 2009 01:47 GMT

Ninety-six clinical isolates of Staphylococcus aureus from Nigeria were characterized phenotypically and genetically. Twelve multidrug-resistant methicillin (meticillin)-resistant S. aureus (MRSA) isolates carrying a new staphylococcal cassette chromosome mec element and a high proportion of Panton-Valentine leukocidin (PVL)-positive methicillin-susceptible S. aureus (MSSA) isolates were observed. The cooccurrence of multidrug-resistant MRSA and PVL-positive MSSA isolates entails the risk of emergence of a multidrug-resistant PVL-positive MRSA clone.

via Cooccurrence of Predominant Panton-Valentine Leukocidin-Positive Sequence Type (ST) 152 and Multidrug-Resistant ST 241 Staphylococcus aureus Clones in Nigerian Hospitals — Okon et al. 47 (9): 3000 — Journal of Clinical Microbiology.