News Scan for Nov 01, 2016

News brief

WHO details 7 recent Saudi MERS cases

The World Health Organization (WHO) today detailed seven cases of MERS-CoV reported by the Saudi Arabian Ministry of Health (MOH) between Sep 16 and Oct 10. Three of the cases are linked to direct or indirect contact with camels, including drinking raw camel milk. The sources of exposure are being investigated in the remaining four cases.

The four cases with unknown exposure were all in men. A 28-year-old male expatriate in Hail, and a 43-year-old male expatriate in Riyadh, both with no known risk facts for MERS-CoV (Middle East respiratory syndrome coronavirus) remain hospitalized in stable condition. They were diagnosed on Oct 8 and Sep 22, respectively, and have no co-morbidities. A 52-year-old Saudi man from Wadi ad-Dawasir is in critical condition after being hospitalized on Sep 19. He had co-morbidities. Finally a 70-year-old Saudi from Hail died on Sep 27 after being admitted to the hospital on Sep 13.

A 51-year-old Saudi woman from Al Kharj was diagnosed as having MERS on Sep 29. She had contact with camels in the 2 weeks prior to symptom onset and remains in critical condition in an intensive care unit. Both a 78-year-old Saudi woman from Sakakah and 50 year-old man from Shaqra remain in stable condition with MERS. Both had a history of drinking raw camel milk.

The update does not include a group of three recently reported healthcare-related cases in Arar, among other cases.
Nov 1 WHO update

Study links humidity and temperature to flu outbreaks

Absolute humidity and temperature are the two environmental factors linked to flu outbreaks, shedding new light on what might help drive disease activity in tropical locations, which had previously been harder to pinpoint. A team based at Scripps Institution of Oceanography published its findings yesterday in Proceedings of the National Academy of Sciences (PNAS).

Flu activity in temperate countries is known to relate to changes in temperature and absolute humidity, but the picture has been less clear for tropical regions that experience less climate fluctuation.

The researchers used an empirical dynamic modeling approach designed to predict flu outbreaks based on absolute humidity, temperature, relative humidity, and precipitation. They incorporated World Health Organization (WHO) data on lab-lab confirmed flu from Jan 1, 1996, to Mar 26, 2014, and National Oceanic and Atmospheric Administration weekly temperature and absolute humidity data for each country.

The researchers found that absolute humidity drives flu activity across different latitudes, with the temperature determining whether the association is positive or negative, with the balance shifting at around 70° to 75°F.

At all latitudes, temperature and absolute humidity were more potent drivers of flu activity than were relative humidity and precipitation. The authors wrote that the findings offer a unified explanation for how environmental factors affact global flu outbreaks.

The findings help set the stage for lab studies to test the threshold, with results that could someday support public health measures such as placing humidifiers in schools and hospitals in cold, dry temperate winters or using dehumidifiers or air conditioners in public buildings in the tropics when the temperature is above 75°F.
Oct 31 PNAS report

In its latest global flu update yesterday, meanwhile, the WHO said disease activity in the Southern Hemisphere continues to decline, including in Australia, where flu activity—dominated by H3N2—peaked in September.

Northern Hemisphere countries are still at interseasonal levels, and globally only a few countries are reporting upticks. Examples include Cuba, French Guiana, Costa Rica, Laos, and Thailand.

Testing at WHO-affiliated labs in the first half of October showed that 85.3% of flu detections were influenza A, and, of subtyped influenza A samples, 93.4% were H3N2.
Oct 31 WHO global flu update

Study: Fully cleansing robot surgical instruments almost impossible

Completely removing all contamination from robotic surgical instruments is nearly impossible, even after multiple cleanings, according to Japanese researchers who reported their findings yesterday in Infection Control and Hospital Epidemiology.

The team collected instruments immediately after surgery or in-house cleaning and measured residual protein levels after three repeated cleanings. For comparison, they also used the same methods to gauge residual protein on ordinary surgical tools. In-house cleaning methods included manual ultrasonication based on manufacturers' directions. The researchers examined 132 robotic and ordinary instruments over a 21-month period at facilities in Japan.

Robotic tools had more protein residue and lower cleaning efficacy compared with the ordinary tools, with 97.6% cleaning effectiveness for the robotic tools and 99.1% for the ordinary tools. Investigators said the complex structure of the robotic tools makes them more difficult to clean and that the findings point to a need to establish new cleaning methods based on repeated residual protein measurements, rather than just one.

Yuhei Saito, RN, PHN, MS, lead author of the study and assistant professor at the University of Tokyo Hospital, said in a press release from the Society for Healthcare Epidemiology of America (SHEA), the publisher of the journal, said the robotic instruments are wonderful tools that allow surgeons to operate with care, but complete decontamination has been a challenge. "By implementing new cleaning procedures using repeated measurements of the level of contamination on an instrument more than once, we could potentially save many patients from future infections."
Oct 31 Infect Control Hosp Epidemiol abstract
Oct 31 SHEA press release

Antimicrobial Resistance Scan for Nov 01, 2016

News brief

AAP updates guidelines on fluoroquinolone use in children

The American Academy of Pediatrics (AAP) yesterday released updated guidelines on the use of fluoroquinolones in children. The clinical report, published in Pediatrics by the AAP Committee on Infectious Diseases, highlights the indications, adverse event profile, and practical prescribing information for pediatricians and includes new data available since the report was last published in 2011.

The core message of the updated AAP guidelines remains unchanged from 2011. It advises that fluoroquinolones are broad-spectrum agents that should not be used as first-line systemic therapy in children and should be considered selectively for children or adolescents only for specific clinical situations. Those situations include when an infection is caused by a multidrug-resistant pathogen for which there is no safe and effective alternative, or when oral therapy is preferable to parenteral therapy.

Currently, fluoroquinolones have limited Food and Drug Administration (FDA) approval for systemic use in children. Ciprofloxacin is FDA-approved for inhalation anthrax, plague, complicated urinary tract infections, and pyelonephritis in children. Levofloxacin is approved for inhalation anthrax and plague.

But the new guidelines also indicate that levofloxacin can be considered in lower respiratory tract infections when a child has a severe allergy to penicillin and in upper respiratory tract infections when the pathogens shows high resistance to penicillin. Ciprofloxacin is suggested as a viable alternative for gastrointestinal infections due to Salmonella or Shigella, but only when alternative antibiotics are unavailable. In addition, the report notes that several topical fluoroquinolones are approved for treatment of bacterial conjunctivitis and otitis externa.

"In the case of fluoroquinolones, as is appropriate with all antimicrobial agents, prescribing clinicians should verbally review common, anticipated, potential adverse events, such as rash, diarrhea, and potential musculoskeletal or neurologic events, and indicate why a fluoroquinolone is the most appropriate antibiotic agent for a child's infection," the authors conclude.
Oct 31 AAP clinical report

Study finds colistin resistance in bacteria exposed to common disinfectant

A study published yesterday in Antimicrobial Agents and Chemotherapy has found that Klebsiella pneumoniae bacteria exposed to an antiseptic commonly used in homes and healthcare settings can become resistant to the last-resort antibiotic colistin.

The study, conducted in England, builds on previous research showing that K pneumoniae strains are able to adapt to increasing concentrations of chlorhexidine, an antiseptic that is found in mouthwash, wound dressings, and solutions for skin antisepsis. The purpose was to determine whether adaptation to chlorhexidine can cause cross resistance to other antibiotics, and to determine the underlying mechanisms of resistance. To figure that out, investigators selected specific strains of K pneumoniae typically found in clinical settings and exposed them to increasing concentrations of chlorhexidine.

The investigators found that in five of six K pneumoniae strains, adaptation to chlorhexidine also led to resistance to colistin without significant loss of fitness or virulence. In addition, they found that adaptation to chlorhexidine and resistance to colistin appeared to be linked to specific gene mutations.

The findings are significant for several reasons. One is that chlorhexidine is a critical part of current infection control practices, especially the treatment of wounds. "The development of increased resistance to this compound has potential implications for our ability to prevent infections during routine and emergency surgery, and during admission to hospitals," study co-author J. Mark Sutton, PhD, of Public Health England, said in an American Society for Microbiology (ASM) news release.

Furthermore, the findings indicate another source of selection pressure for colistin, a powerful antibiotic that is becoming more necessary with the growth of multidrug-resistant organisms. The emergence of colistin resistance in Klebsiella—which is already increasingly resistant to several antibiotic classes, including carbapenems—could present healthcare providers with life-threatening infections that are extremely hard to treat.

In addition, there is concern that specific selective pressures from antiseptics could create similar mutations that confer increased resistance to antibiotics in different species of bacteria.
Oct 31 Antimicrob Agents Chemother study
Oct 31 ASM news release