News Scan for Jul 22, 2014

News brief

Final report on E coli lettuce outbreak notes two additional products

The California Department of Public Health (CDPH) yesterday released a final report on a 2013 Escherichia coli outbreak traced to pre-packaged salads sold at Trader Joe's stores that sickened 33 people in four states, Food Safety News (FSN) reported today.

The report contains new information, including two previously unreported salad products linked to the outbreak: one produced by Glass Onion for Walgreens, and one made by an unnamed Oakland, Calif., company.

Two Glass Onion salad products had already been identified early in the outbreak: Trader Jose's Mexicali Salad with Chili Lime Chicken and Trader Joe's Field Fresh Chopped Salad with Grilled Chicken. Both were produced by Atherstone Foods Inc., of Richmond, Calif.

All four salads contained romaine lettuce harvested and shipped by Ratto Bros. of Modesto, Calif., and grown by Lake Bottom Farms LLC.

After finding no positive samples at Glass Onion catering, investigators obtained samples from Ratto Bros. farms and found E coli in 5 of 44 environmental samples. But the E coli O157:H7 samples were not from the premises, only nearby, and they did not match the O157:H7 outbreak strain.

The investigators could not pinpoint how the salads became contaminated, FSN reported. Since the inspection, according to the report, Ratto Bros. has implemented new and improved procedures to lower the risk of future contamination.
Jul 21 CDPH report (8.5 MB)
Jul 22 FSN story

Somalia confirms 4 new polio cases

Somalia has confirmed 4 new polio cases so far this year, in its remote Jariban district in Mudug region in the country's northeast, the World Health Organization (WHO) Eastern Mediterranean Regional Office (EMRO) said today.

The 2014 infections bring the total number of cases to 198 since an outbreak was confirmed in the country in May 2013. Somalia's health ministry, with WHO support, carried out case investigations and outbreak response in the affected region.

"Responding to the polio outbreak is one of the top priorities of the UN and the humanitarian community at large," said the UN resident and humanitarian coordinator for Somalia, Philippe Lazzarini, in a WHO/EMRO press release.

Since January, health officials have conducted nine rounds of vaccinations, and they will continue immunization efforts throughout the year. The campaigns have targeted more than 1.5 million children younger than 5 years and close to 5.5 million older children. The current round of vaccinations will run until Jul 25 and target close to 500,000 kids under 10 years old, WHO/EMRO said.
Jul 22 WHO/EMRO press release

Flu Scan for Jul 22, 2014

News brief

CDC: Retracing avian flu sample contamination may be impossible

Officials from the US Centers for Disease Control and Prevention (CDC) said yesterday that it might be impossible to trace how H9N2 avian flu samples it sent to a US Department of Agriculture (USDA) lab in Athens, Ga., became cross-contaminated with the lethal H5N1 strain, Reuters reported yesterday.

Tom Skinner, a CDC spokesman, told Reuters that most of the virus culture materials used in the labs were discarded shortly after the scientists completed their work in March.

In the wake of an in investigation into possible anthrax exposure at another CDC lab, the agency recently revealed the flu cross-contamination incident, which Director Tom Frieden, MD, MPH, said on Jul 11 that he had just learned about. The lab safety lapses were the subject of a US House of Representatives subcommittee hearing on Jul 16.
Jul 21 Reuters story

In a related development, the American Society for Microbiology (ASM) yesterday posted a statement on the recent federal biosafety lapses.

Timothy J. Donohue, PhD, the group's president, and Ronald Atlas, PhD, chairman of the public and scientific affairs board, referenced the CDC's Jul 11 report on potential exposure to anthrax, reminding microbiologists working at all levels of the need to take all steps possible to protect themselves, their coworkers, and the public from disease-causing pathogens.

They urged ASM members to take the highest levels of responsibility and accountability in their labs. "This work must be conducted as safely as possible. Toward that end, we urge microbiologists to review their laboratory procedures and to ensure that they are compliant with biosafety regulations and best practices," they said in the statement.

The two ASM officials said microbiologists and institutions should regularly inventory all areas of storage to ensure that all samples are accounted for and to promptly report all lapses in biosafety and biosecurity.
Jul 21 ASM statement on biosafety lapses

Topical adjuvant shows promise for flu vaccine in seniors

Using imiquimod as a topical adjuvant appears to boost the effect of intradermal flu vaccination in older people with underlying medical conditions, according to a study from Hong Kong researchers yesterday in Clinical Infectious Diseases.

The strategy had shown promising findings in mouse studies, prompting questions about whether it could be useful in older people, who typically have weaker immune responses to flu vaccination.

The prospective, double-blind randomized control trial was conducted in 2012 and followed 91 adults, average age 73. They received one of three vaccinations: topical imiquimod ointment followed by intradermal trivalent influenza vaccine (TIV), a topical aqueous cream followed by intradermal TIV, and a topical aqueous cream followed by intramuscular TIV.

To evaluate safety, participants were observed for 30 minutes after they were vaccinated and were asked to record local and systemic adverse effects for 7 days.

Researchers obtained blood samples for antibody assays at baseline; at days 7, 14, and 21; and at 1 year after vaccination. Researchers measured antibody titers with standard hemagglutinin-inhibition and microneutralization assays.

By day 7, 27 of 30 patients (90%) who received imiquimod with the intradermal vaccine seroconverted against the H1N1 strain, compared with 4 of 30 (13%) who received the aqueous cream and intramuscular vaccine and 12 of 31 (39%) who received the aqueous cream plus the intradermal vaccine. Those who received the imiquimod combination met protection correlates for all three strains 2 weeks earlier than for the other groups, along with better seroprotection rates that were sustained for up to 1 year.

The team also found fewer hospitalizations for flu and pneumonia among the imiquimod group, and they reported that adverse reactions were self-limiting. They concluded that pretreatment with imiquimod significantly speeded, boosted, and prolonged the immunogenicity of flu vaccination, a strategy they said should be pursued for older people.
Jul 21 Clin Infect Dis abstract