Stewardship / Resistance Scan for Nov 16, 2017

News brief

Canadian patient identified with rare ceftriaxone-resistant gonorrhea

Canadian researchers have identified a ceftriaxone-resistant Neisseria gonorrhea isolate in a Canadian patient, according to a new report in Emerging Infectious Diseases. It's one of only a handful of ceftriaxone-resistant N gonorrhea isolates reported worldwide.

The isolate was identified in a 23-year-old woman who tested positive for gonorrhea in January 2017. Antimicrobial susceptibility testing indicated that the isolate was non-susceptible to ceftriaxone and cefixime but susceptible to azithromycin. Tests of cure 14 days after initial treatment with azithromycin and cefixime came back negative, suggesting the azithromycin was effective in treating the infection.

Testing of two previous sexual partners for gonorrhea also came back negative, but one of the men reported unprotected sexual activity during a trip to China and Thailand in November 2016.

Whole genome sequencing showed that the isolate belonged to multilocus sequence type ST1903 and contained a mosaic penA allele (penA-60); these elements are identical to those found in a ceftriaxone- and multidrug-resistant N gonorrhea isolate reported in Japan in 2015. The authors of the study say the epidemiologic information suggests the international spread of a penA allele associated with high-level ceftriaxone resistance.

Rising resistance to the combination therapy of azithromycin and ceftriaxone or cefixime—the last remaining effective treatment for gonorrhea—has raised concerns about the global emergence of untreatable gonorrhea.
Nov 13 Emerg Infect Dis study

Chinese study shows prevalence, characteristics of E coli clone

More than 11% of Escherichia coli isolated from patients at a Chinese hospital belong to the extensively drug-resistant sequence type (ST) 131 clonal group, researchers reported yesterday in Antimicrobial Resistance and Infection Control.

For the study, researchers at a Chinese university hospital collected a total of 700 non-duplicate E coli isolates obtained from urine, blood, miscellaneous sources from August 2014 to August 2015. Isolates belonging to ST131 were identified by polymerase chain reaction testing and multilocus sequence typing and were also characterized for antibiotic resistance levels, resistance genes, and virulence factors.

Overall, 83 isolates (11.6%) were identified as belonging to the ST131 clonal group, which is similar to rates reported previously. The H30 lineage, an important ST131 subclone that has become the most dominant and extensively distributed multidrug-resistant lineage of E coli worldwide, accounted for 63.9% of the isolates. Results of O typing revealed that the ST131 isolates belonged to two types—O25b-B2-ST131 (66.3%) and O16-B2-ST131 (33.7%).

The researchers say that although O25b-B2-ST131 remains the predominant ST131 clone type in China, the high percentage of O16-B2-ST131 identified in the study indicates the subclone may be an important type of E coli ST131 in China and should be further investigated.
Nov 15 Antimicrob Resist Infect Control study

Dutch researchers find single-room ICU design reduced MDR pathogens

A study in the Netherlands indicates that transforming an intensive care unit (ICU) into single-occupancy rooms helped reduce transmission of multidrug-resistant (MDR) pathogens, Dutch researchers reported yesterday in Antimicrobial Resistance and Infection Control.

The single-center retrospective study looked at two periods at a Dutch ICU: A first period from January 2002 to April 2009 and second period from May 2009 to March 2013. In the first period, the patients were treated in an ICU with 21 beds located in five single rooms, two double rooms, and an open bay. This unit was closed on two occasions because of outbreaks of extended-spectrum beta lactamase-producing Klebsiella pneumoniae (ESBL-Kp) and MDR Acinetobacter baumannii. In May 2009, the patients were transferred to a newly built ICU with 9 single-occupancy rooms.

The two periods were compared with respect to the occurrence of representative MDR gram-negative (MDR-GN) bacteria. Routine microbiological screening was performed on all patients on admission to the ICU and then twice a week. To assure comparability, the two periods were approximately identical with respect to number of admissions, number of beds, and bed occupancy rate, per year and per month.

The results showed that despite infection prevention efforts—including improved hand hygiene, use of contact precautions, isolation of ESBL-Kp patients, and temporary ward closure on two occasions—high prevalence of MDR-GN bacteria continued to occur during the first period. After the move to the single-room ICU, a clear and sustained decrease in MDR-GN bacteria was observed.

"Our results provided strong evidence that the single room policy as an infection control strategy has contributed significantly to the control of cross transmission of resistant pathogens in the ICU," the authors write.
Nov 15 Antimicrob Resist Infect Control study

News Scan for Nov 16, 2017

News brief

Monitoring period nears end for Marburg outbreak contacts

Tests on a traditional healer in Kenya who was a contact of one of the lab-confirmed Uganda Marburg patients has tested negative, and other high-risk contacts in Kenya have completed their 21-day monitoring periods, with no other illnesses detected, the World Health Organization (WHO) said yesterday.

Meanwhile, in Uganda, the number of contacts still being monitored is down to 56 in Kween district, all of whom are expected to complete their 21-day monitoring period today.

The WHO said enhanced surveillance for the disease will continue until Dec 7.

So far, the Marburg outbreak has been limited to a 3-case family cluster, an index patient who is considered a probable case and the man's sister and brother, both of whom had lab-confirmed infections. All three died from their illnesses.

Though Uganda has experience managing Ebola and Marburg outbreaks and responded quickly, the WHO said global health officials have been worried about spread to neighboring Kenya, which has limited experience with the diseases and is facing a health worker strike that could have slowed down the public health response. Also, the affected border area between the two countries is home to caves at Mount Elgon National Park that harbor large fruit bat colonies that are known to transmit Marburg virus.
Nov 15 WHO statement

Text message reminders prove inexpensive tool for flu vaccination

A new study from Western Australia shows that sending a text message reminder was a low-cost intervention that resulted in more flu vaccine uptake among a high-risk population.

The randomized control trial was conducted on 12,354 high-risk patients who had their phone numbers listed at their doctor's office, according to a report yesterday in the Annals of Family Medicine. Half of the participants received texts—which the researchers called short message service (SMS) reminders—prompting them to get the vaccine, while the other half did not. The messages were sent 6 weeks after the vaccine became available.

Twelve weeks after receiving the text reminder, 12% of the intervention group had received the vaccine, compared with 9% of controls. Researchers found that for every 29 messages sent, at a cost of $3.48 (USD), one additional high-risk patient was immunized.

Parents of children under the age of 5 were twice as likely as control parents to vaccinate their children if they received a text message reminder, the authors said. There was no observed effect, however, on pregnant women

"Despite the potential limitations, the SMS messages in this RCT [randomized controlled trial] cost, in aggregate, $741 and resulted in 221 additional high-risk patients being vaccinated against influenza," the authors concluded.
Nov 15 Ann Fam Med study

Led by Venezuela, nations in Americas report high levels of diphtheria

In an epidemiologic update yesterday, the Pan American Health Organization (PAHO) says five countries in the Americas have reported confirmed or suspected diphtheria cases this year. So far, 205 have been confirmed, putting the region well ahead of the 2016 total of 78 confirmed cases.

Brazil, Colombia, Haiti, the Dominican Republic, and Venezuela all have reported suspected and confirmed cases. Thus far in 2017, Venezuela has had 511 suspected cases. Children and young adults from 5 to 19 years are the most affected age-group. The country has increased its vaccination efforts as a response to the cases, PAHO said.

Haiti has confirmed 51 cases, including 7 deaths. Among the confirmed case-patients 26% were vaccinated, 33% were not vaccinated, and the vaccination status was unknown for 41%. Neighboring Dominican Republic has reported only 3 confirmed cases this year and no deaths.

All 14 suspected cases in Colombia have been discarded. Brazil however has had 5 confirmed cases, including 1 death.
Nov 15 PAHO report

WHO calls to end blockade in Yemen, citing humanitarian, health crisis

Today members the WHO and United Nations urged a Saudi-led military coalition to lift Yemen's blockade because it is preventing the country from getting humanitarian aid and supplies, including materials used to fight an ongoing cholera outbreak.

"More than 20 million people, including over 11 million children, are in need of urgent humanitarian assistance. At least 14.8 million are without basic healthcare and an outbreak of cholera has resulted in more than 900,000 suspected cases," said WHO Director-General Tedros Adhanom Ghebreyesus, MD.

Though the military coalition in place in Yemen has partially lifted the blockage, the WHO estimates that up to 150,000 malnourished children could die from hunger in the coming months if the ban is not completely lifted.

Though the almost-900,000-case cholera outbreak has stabilized, Yemen is suffering new public health threats, including diphtheria. In recent weeks officials have reported 120 clinically diagnosed diphtheria cases and 14 deaths, and at least 1 million children are now at risk of contracting the disease, the WHO said.
Nov 16 WHO statement

Surveillance shows avian flu viruses fairly common in wild birds in Brazil

Scientists who studied samples obtained in 2009 to 2012 from wild birds at a major wintering site in Southern Brazil identified RNA from multiple avian flu subtypes, predominantly H6N1, that are more similar to viruses of South American lineage than of North American lineage, according to a study yesterday in Influenza and Other Respiratory Viruses.

Researchers from Brazil and St. Jude Children's Research Hospital in Memphis, Tenn., obtained samples over the 4-year study period in Lagoa do Peixe National Park because few data have been published about avian flu viruses in migratory birds in South America. They obtained 1,212 oropharyngeal and cloacal samples and screened them for flu viruses via polymerase chain reaction testing.

They reported that 48 samples (4%) contained detectable influenza virus RNA. Partial sequences from 12 of the isolates showed the presence of H6N1 in 8 samples and H2N2, H6, H9N2, and H12N5 in 1 sample each. Phylogenetic analyses of the 9 H6 viruses showed they were most similar to viruses of the South American lineage. The H6N1 viruses caused no signs of disease in ferrets, which are used for a human model of influenza infection.

The investigators also noted that levels of flu viruses in birds was highest at the end of their wintering period.
Nov 15 Influenza Other Respir Viruses abstract