News Scan for Jan 07, 2014

News brief

Biggest US outbreak of highly resistant bacteria tied to Illinois hospital

The largest US outbreak so far of bacteria producing the enzyme NDM (New Delhi metallo-beta-lactamase), which confers resistance to most antibiotics, has been linked to a Chicago area hospital, according to the Chicago Sun-Times and the Centers for Disease Control and Prevention (CDC). The contamination was traced to endoscopic equipment.

The CDC reported last week that 69 patients with carbapenem-resistant Enterobacteriaceae (CRE) were identified in the United States in 2013, and 44 of those involved NDM-producing Escherichia coli in northeastern Illinois. The CDC report said at least 32 cases were linked to the suburban hospital, which the Sun-Times identified as Advocate Lutheran General Hospital in Park Ridge.

"It's the largest outbreak that we’ve seen in the U.S. of this bacteria ever," Alex Kallen, an infectious diseases specialist who supervised the CDC investigation, told the Sun-Times.

Nine patients who tested positive for NDM-producing E coli were identified in northeastern Illinois from March through July of 2013, the CDC reported in Morbidity and Mortality Weekly Report (MMWR). Eight of them were treated at the same hospital, and a case-control study revealed that undergoing endoscopic retrograde cholangiopancreatography (ERCP) was a strong risk factor, the report said.

An NDM-producing E coli strain that was closely related to the outbreak strain was recovered from the device used. The hospital notified ERCP patients of the problems, and 109 returned for testing, according to the Sun-Times. The story indicated that 28 were colonized but not infected, while 10 others had signs and symptoms, and a "small percentage" were treated with antibiotics.

The CDC said investigators found no lapses in cleaning procedures used on the ERCP equipment, but the findings prompted the hospital to switch from high-level disinfection to gas sterilization of the devices. "The design of the ERCP endoscopes might pose a particular challenge for cleaning and disinfection," the report said.
Jan 5 Sun Times story
Jan 3 MMWR article

CDC submits IND for meningococcal vaccine use at UCSB

As part of the response to a serogroup B meningococcal disease outbreak at the University of California at Santa Barbara (UCSB), the CDC is taking steps to enable an unlicensed vaccine to be used to prevent additional infections.

The CDC said in a Dec 31 update that is submitting an investigational new drug (IND) application with the Food and Drug Administration (FDA), which would allow the vaccine to be used in at-risk groups at UCSB. In November the FDA approved an IND for Bexsero, made by Novartis, that cleared the way for the vaccine to be used to curb a separate outbreak at Princeton University.

The outbreak at UCSB has sickened four students, permanently disabling one of them, and the strain has a different genetic fingerprint than the serogroup B organism responsible for the Princeton illnesses. Bexsero, made by Novartis, targets serogroup B, which is not covered by the US meningococcal vaccines. Bexsero is approved in Europe, Australia, and Canada.

The CDC said the decision to pursue the IND was made after reviewing the cases and with the support of college, county, and state health officials. Health officials concluded that more cases were likely to occur at UCSB. It said IND clearance can take several weeks and that lab tests show that the serogroup B vaccine is effective against the strain that caused the UCSB cases.

In a Dec 23 letter to students, parents, and staff, UCSB health officials said the process to gain access to the vaccine is progressing as rapidly as possible, but there are still many steps that need to take place, including determining the population that should receive the vaccine.
Dec 31 CDC Q and A
Dec 23 UCSB letter

VA care facilities report drop in healthcare-related MRSA

Healthcare-associated methicillin-resistant Staphylococcus aureus (MRSA) infections dropped 36% 4 years after Veterans Affairs (VA) long-term care facilities implemented a nationwide prevention initiative, according to a study in the January issue of the American Journal of Infection Control, published by the Association for Professionals in Infection Control and Epidemiology (APIC).

Staff implemented the MRSA Prevention Initiative in the VA's 133 long-term care facilities in January 2009. The initiative includes screening every patient for MRSA, use of gowns and gloves when caring for patients colonized or infected with MRSA, hand hygiene, and an increased focus on infection control. It also created a MRSA prevention coordinator at each center.

From July 2009 to December 2012, the mean quarterly MRSA admission rate increased from 23.3% to 28.7%, but the overall rate of MRSA healthcare-associated infections (HAIs) dropped 36%, from 0.25 to 0.16 per 1,000 resident-days.

The authors note the decreased rate of MRSA HAIs despite no decrease in overall MRSA. "To our knowledge, declines in MRSA HAIs such as this have not been reported in other large long-term care settings," they conclude.
January Am J Infect Control abstract
Jan 6 APIC news release on the study

Flu Scan for Jan 07, 2014

News brief

Guangdong province man hospitalized with H7N9

Another H7N9 case has been detected in China, the ninth such infection to be reported in Guangdong province, where several of the country’s recent infections have been found.

Hong Kong’s Centre for Health Protection (CHP) said in a statement that the patient is a 31-year-old man who lives in Shenzhen. He started having symptoms on Dec 30 and was hospitalized on Jan 3, where he is in stable condition.

The man has not had recent contact with poultry. The CHP said 35 of his close contacts were placed under medical surveillance, and so far no other H7N9 illnesses have been found.

The CHP noted, though, that it is following up on notification from Guangdong health officials that two of the contacts are Hong Kong residents, a 4-year-old girl and her 37-year-old mother who had traveled to Shenzhen from Dec 26 through Jan 6. The CHP’s contact tracing found that the girl has been asymptomatic and the mother came down with a sore throat yesterday. The girl and her mother have been isolated in the hospital, where their respiratory samples will be tested.

The man’s infection pushes the global number of H7N9 cases to 149.
Jan 7 CHP statement

In other developments, a telephone survey of Chinese citizens 2 weeks after the first H7N9 case was detected found a moderately high anxiety level, with a high level of trust in the government, according to a study published today in BMC Infectious Diseases. The researchers are from Shanghai and London.

The survey of 1,011 Shanghai respondents also found that people blamed the threat on hygiene levels, temperature changes, dead pigs floating in the Huangpu River, and recent migration to the city. They also said early news of the outbreak prompted them to buy preventive medicines.

Researchers said the findings suggest that the public values local expertise and transparency and that early anxiety about an outbreak can drive demand for certain products, potentially leading to shortages.
Jan 7 BMC Infect Dis abstract

Study hints at ethnic differences in cell-based H7N9 protection

Some ethnic groups, such as native people in Alaska and Australia, may be especially vulnerable to H7N9 infection, based on genetic factors that drive the cell-based response to flu viruses, an international research team based at the University of Melbourne reported yesterday in Proceedings of the National Academy of Sciences (PNAS).

People lack protective antibodies to the new virus, and several research teams are looking into the extent of cell-based protection. The PNAS study focused on how well cross-reactive CD8+ T lymphocytes (CTL) might protect against H7N9. When they compared the virus against other flu viruses, they found that 28% of the H7N9 peptides had the capacity to provoke a CTL response.

In the next part of the study, they examined blood cells from 52 healthy donors who had not been exposed to the H7N9 virus to estimate human leukocyte antigens (HLAs) that are able to present immunogenic influenza peptides to CTLs, which they estimated to range from 16% to 57% in the population.

The percentage varied by ethnicity, with some HLA alleles showing a robust CTL response against any influenza A virus, including H7N9. Other alleles that were more prevalent in indigenous Alaskan and Australian people showed a more limited CTL response.

The researchers noted that the findings were consistent with mortality during the 1918 pandemic and also reflected hospitalization and mortality patterns seen during the 2009 H1N1 pandemic. Although social and demographic factors likely played a role, genetic factors could have also played a role, they noted.

Clinical outcomes in Chinese patients infected with H7N9 could also be influenced by the level of cross-reactive CTL memory, the team wrote.
Jan 6 PNAS study

Study finds no rise in GBS with H1N1 vaccine in Europe

The risk of Guillain-Barre syndrome (GBS) was not elevated by pandemic 2009 H1N1 (pH1N1) vaccination in several European nations, a new PLoS One study found.

Researchers performed a self-controlled case series analysis on data from Denmark, Finland, France, the Netherlands, Norway, Sweden, and the United Kingdom during the 2009-10 pandemic. They identified 303 cases of GBS and Miller Fisher syndrome, a GBS variant. Of those, 99 were exposed to pH1N1 vaccines, most often adjuvanted Pandemrix and Focetria.

The unadjusted pooled relative incidence (RI) for pH1N1 vaccination and GBS was 3.5, based on all countries. This dropped to 2.0 after adjustment for month of the year and to 1.9 when the researchers accounted for contraindications.

In a subset involving only Dutch, Norwegian, and UK data, the team further adjusted for other confounders, which decreased the RI from 1.7 (adjusted for calendar month) to 1.4, which they report as the main finding.
Jan 3 PLoS One study