Stewardship / Resistance Scan for Dec 18, 2019

News brief

Contact with puppies tied to MDR Campylobacter in 13 states

Puppies from Petland pet stores are again implicated in a multistate outbreak of multidrug-resistant (MDR) Campylobacter infections, this time affecting at least 30 people in 13 states, the Centers for Disease Control and Prevention (CDC) said yesterday in an update.

Four people have been hospitalized in this outbreak, caused by Campylobacter jejuni, but none have died. "Epidemiologic and laboratory evidence indicate that contact with puppies, especially those at pet stores, is the likely source of this outbreak," the CDC said. The agency added, "Laboratory evidence indicates that bacteria from ill people in this outbreak are closely related genetically to bacteria from ill people in the 2016–2018 outbreak of multidrug-resistant Campylobacter infections linked to pet store puppies."

In both the current and earlier outbreaks, the CDC named Petland stores as a likely source of the contaminated puppies. Of 15 people in the current outbreak who reported contact with a puppy from a pet store, 12 (80%) were linked to Petland, including 5 employees.

The 2016-18 MDR Campylobacter outbreak involved 113 cases and 23 hospitalizations in 17 states. The CDC posted its final outbreak notice on that event on Jan 30, 2018.

Illnesses in this year's outbreak began from Jan 6 to Nov 10, with patients ranging from 8 months to 70 years. Whole-genome sequencing of 26 isolates from patients predicted antibiotic resistance to tetracycline (26 isolates), ciprofloxacin (25), nalidixic acid (25), azithromycin (23), erythromycin (23), clindamycin (23), telithromycin (23), and gentamicin (18).
Dec 17 CDC statement
Jan 30, 2018, CDC final notice on previous outbreak

ECDC details CRE outbreak in Lithuanian hospitals

The European Centre for Disease Prevention and Control (ECDC) today issued a report on an outbreak of Klebsiella pneumoniae carbapenemase-producing carbapenem-resistant Enterobacteriaceae (KPC-CRE) in Lithuania.

According to the ECDC's rapid risk assessment, 199 KPC-CRE cases were detected from Feb 1 through Nov 26, with 186 cases (93%) occurring in a single hospital (hospital 1). The cases include infections as well as carriage, and most of the isolates were Klebsiella pneumoniae (186 cases, 93%), followed by Escherichia coli (16 cases, 8%), Citrobacter freundii (2 cases), and Enterobacter aerogenese (1 case). In all isolates, carbapenem resistance was mediated by the KPC enzyme. Additional resistance to colistin was detected in 26 of 52 isolates tested.

The outbreak was first identified in April 2019, with the first case detected in a patient with a surgical-site infection admitted to the intensive care unit of hospital 1, and was still ongoing as of Dec 11.

"The risk of further spread of CRE in the most-affected hospital is high, as a large number of cases have been identified from multiple wards and new cases continue to be detected at the time of this risk assessment," the report says. "While enhanced infection control measures have been implemented, the outbreak appears not yet to have been controlled."

Six additional hospitals have also reported KPC-CRE cases, and the ECDC says the risk of further spread in the Lithuanian health system is high, since screening for CRE carriage was not in place in Lithuanian hospitals before December 2019. Lithuania reported only 5 and 12 cases of CRE in 2017 and 2018, respectively.

The ECDC says screening of patients at high risk for digestive tract carriage of CRE due to healthcare contact in the preceding 12 month, along with pre-emptive contact precautions and isolation, should be considered. Further epidemiologic investigations are ongoing.
Dec 18 ECDC rapid risk assessment

Resistant E coli intestinal carriage found in VA patients, housemates

Veterans Affairs (VA) patients and members of their household commonly carry and share a strain of multidrug-resistant E coli that's emerged as a common source of extra-intestinal infections in hospitals, researchers from the University of Minnesota and the Minneapolis VA Medical Center reported today in the Journal of Infectious Diseases.

For the study, the researchers screened fecal samples from 741 volunteers (383 VA patients and 358 household members, including pets) for fluoroquinolone-resistant E coli (FQREC) and E coli sequence type (ST) 131. They were specifically interested in the H30 subclone within ST131, and its fluoroquinolone-resistant H30R subset, both of which have expanded rapidly in recent years. Because these extra-intestinal pathogenic E coli strains usually originate in patients' gut microbiota before causing extra-intestinal infections, it's been theorized that widespread gut colonization could underlie epidemic clonal emergence.

The results showed that colonization prevalence was 5.1% for H30R, 8% for ST131 (67% FQREC), and 10% for FQREC (52% ST131). Among the 425 strains that underwent virulence genotyping, ST131 isolates exhibited more virulence genes than non-ST131 isolates. Strain sharing appeared in 27% of the 100 assessed multi-subject households and 18% of corresponding subjects, and was associated with the elderly, FQREC, H30R, H30Rx, E coli ST73, and specific virulence genes. Comparison of fecal ST131 and FQREC isolates with a collection of clinical E coli isolates from Minneapolis VA patients found similarities in virulence gene content, resistance profiles, and other traits, a finding that supports the idea that the clinical strains emerge from the gut reservoir.

"In conclusion, as an intestinal colonizer of uninfected veterans and their human household members, H30R was much more prevalent than any other FQREC strain, largely independent of the studied host characteristics," the authors of the study write.

"Comparative prevalence values suggested that, relative to other FQREC, H30R is likely both a better gut colonizer and more capable of causing infections in colonized hosts, phenotypes possibly promoted by H30R's extensive repertoire of virulence factors, which may also represent colonization factors. Thus, colonization fitness, virulence, and within-household strain sharing may all underlie H30R's epidemic success, and could be targets for preventive interventions."
Dec 18 J Infect Dis abstract

News Scan for Dec 18, 2019

News brief

Two new Ebola cases recorded in DRC

According to the World Health Organization (WHO's) Ebola dashboard, two new cases of the viral disease were recorded today in the Democratic Republic of the Congo (DRC), raising the outbreak total to 3,351 cases including 2,217 deaths.

Officials are still investigating 519 suspected cases

In the latest situation report on the outbreak, the WHO said 24 new cases of Ebola were recorded from Dec 9 to 15, marking a resurgence of the virus in the wake of widespread violence in Beni.

At least 24 new cases in Mabalako and Beni are linked to a single transmission chain, based on one case-patient who suffered a relapse of Ebola within a 6-month period. It was not known if the patient had suffered a relapse or was re-infected, but genetic sequencing suggests the virus relapsed in the patient, the WHO said.

"The majority of recent cases are coming from a single chain of transmission that is linked to a suspected relapse of EVD in an individual," the WHO said. "Although this has led to a number of secondary cases, efforts are being made to closely monitor the cases and their contacts to reduce the risk of tertiary transmission. It is thus of paramount importance that all areas of response are functional and fully resourced to bring an end to this outbreak."
WHO Ebola dashboard
Dec 17 WHO situation report

WHO details November MERS cases in Saudi Arabia

The WHO today offered new details on 10 MERS-CoV cases recorded in Saudi Arabia in November, half of which were connected to camels.

The cases were reported in six different regions, and five involved contact with camels or camel products, a known risk factor for MERS-COV (Middle East respiratory syndrome coronavirus) infection. Four cases were recorded in Riyadh, two in Medina, and one each in Mecca, Taif, Asir, and Al Qassim.

All the patients were men, and none were health workers or secondary cases. One patient, a 38-year-old man from Riyadh, died from his infection.

The WHO said that, from 2012 through Nov 30, 2019, a total of 2,494 laboratory-confirmed MERS cases and 858 associated deaths have been recorded, the vast majority in Saudi Arabia.
Dec 18 WHO update

Inexpensive paper-based test detects Lyme bacteria in early stages

A new inexpensive paper-based test can detect antibodies against the Borrelia burgdorferi bacterium in serum samples, which means it could quickly and accurately identify Lyme disease, a tick-borne illness that affects up to 300,000 American each year. The test is meant for use in the first 30 days after a tick bite, when the telltale "bull's eye" rash may or may not appear.

Authors writing in the journal ACS Nano describe the point-of-care (POC) handheld test as containing a sensing membrane for bacterial antigens and a synthetic peptide. If B burgdorferi bacteria are present, the antigen spots turn different colors. Results appear within 15 minutes.

Fifty blood samples from people with and without early-stage Lyme disease were tested using the paper-based device, and the assay showed a specificity of 96.3% and sensitivity of 85.7%.

Current two-tier tests for Lyme disease catch only 50% of Lyme cases in early stages, the authors said, and cost more than $400 per test, with results typically read in more than 1 day. The new paper-based test costs $0.42 per test.

"The multitarget and portable POC nature of the computational xVFA [multiplexed vertical flow assay] make it uniquely suited for [Lyme] diagnostics, presenting major advantages in terms of time, cost, and performance when compared to (first-tier) EIAs [enzyme immunoassays] with single antigen targets as well as standard two-tier testing methods that are rather costly (e.g., >$400/test) and slow (>24 h for results)," the authors conclude.
Dec 18 ACS Nano study