Costco chicken salad linked to 19 E coli cases from 7 states

Rotisserie chicken salad sold at Costco stores that was contaminated with Shiga toxin–producing Escherichia coli O157:H7 has sickened 19 people in seven states, the US Centers for Disease Control and Prevention (CDC) announced today.

The CDC said epidemiologic investigation so far suggests that the Costco salad at stores in several states is the likely outbreak source. Of 16 people interviewed so far, 14 said they purchased or ate rotisserie chicken salad from Costco. A specific ingredient has not been identified.

The majority of cases are from western states, said the CDC. Affected states include Montana (6), Utah (5), Colorado (4), Washington (1), California (1), Missouri (1), and Virginia (1). Five people have been hospitalized, and two of them have developed hemolytic uremic syndrome (HUS), a potentially fatal kidney complication. Illness onsets range from Oct 6 to Nov 3.

The Colorado Department of Public Health and Environment (CDPHE) said yesterday that four Colorado case-patients purchased chicken salad made with rotisserie chicken from Costco stores on Oct 25 and 26 and became ill between Oct 28 and Nov 3. The affected product was sold as item number 37719.

Colorado's Jefferson County reported two illnesses related to the outbreak, while Arapahoe and Routt counties reported one E coli case each. One person required hospitalization.

The chicken salad is no longer for sale at Costco stores, and the retailer is working with the US Food and Drug Administration (FDA), the US Department of Agriculture (USDA), and the CDC to gain more information about the outbreak.
Nov 24 CDC outbreak announcement
Nov 23 CDPHEupdate

Hawaii dengue fever cluster approaches 100 cases

The Hawaii Department of Health (HDOH) said today that the number of locally acquired dengue fever cases on the big island of Hawaii has risen to 92.

Of the confirmed cases of dengue, 79 are in Hawaii residents, and 13 are in visitors. More than three quarters of the total cases (76%, or 70) have occurred in adults, while 22 cases involve children. Illness onset occurred between Sep 11 to Nov 17.

West Hawaii Today reported today that the outbreak has spread to both sides of the big island of Hawaii and is especially affecting the Kona Coast.

The HDOH has excluded 143 previously reported cases of dengue fever due to negative test results or failure to meet case criteria. The agency is currently monitoring for dengue fever on all Hawaiian islands, as well as carrying out assessment and abatement activities at mosquito breeding sites.
Nov 23 HDOHupdate
Nov 24 West Hawaii Today story
Nov 19 CIDRAP News scan on the outbreak

FDA approves postexposure indication for BioThrax

The FDA yesterday announced the approval of an expanded indication for Emergent BioSolution's BioThrax (Anthrax Vaccine Adsorbed), the only licensed vaccine against Bacillus anthracis. Its decision allows the vaccine to be given to people ages 18 through 65 after suspected or confirmed exposure to B anthracis. Emergent had filed its supplemental Biologics License Application (sBLA) in November 2014. The vaccine was first approved in 1970 for the prevention of anthrax in people at high risk exposure, such as those in the military.

Karen Midthun, MD, director of the FDA's Center for Biologics Evaluation and Research, said in the statement, "With today's approval of BioThrax, we now have a vaccine that can be used, together with antibiotic treatment, to prevent disease after exposure to anthrax spores." The indication is for administration at 0, 2, and 4 weeks after suspected or confirmed exposure.
Nov 23 FDA statement
Nov 11, 2014, CIDRAP News scan "Post-exposure indication sought for BioThrax"

New gene editing technique prevents mosquitoes from spreading malaria

A new technique that allows scientists to insert or remove DNA from a cell's nucleus has succeeded in making mosquitoes pass antimalarial genes to their offspring, according to findings of two studies published yesterday in the Proceedings of the National Academy of Sciences (PNAS).

Scientists at the San Diego and Irvine campuses of the University of California used a method known as clustered regularly interspaced short palindromic repeats (CRISPR) to remove parts of DNA from mosquitoes' cells and insert malarial antibody genes. The CRISPR technique is unique in that it allows inserted genetic elements to be copied to both homologous chromosomes, increasing the likelihood that the mutation will be passed to offspring.

Using the CRISPR method, researchers inserted the Cas9 nuclear enzyme containing antimalaria genes into the germ lines of Anopheles stephensi mosquitoes, one of the top malaria vectors in southeast Asia. The insertion prevented transmission of the malaria-causing parasite, Plasmodium falciparum, to 99.5% of mosquitoes' offspring.

Included with the antimalaria genes were guide RNA that helped target sites for genetic insertion and a protein that gave fluorescent red eyes to offspring in whom transmission of the mutation was successful.

The technique, which appears to successfully change heritable disease-causing traits in a prominent vector, may have promise for eliminating malaria transmission between mosquitoes and humans.
Nov 23 PNAS study

Given the current efforts to prevent global malaria transmission, a separate PNAS study sheds light on how P falciparum may be adapting to infect geographically diverse mosquito species.

Researchers from the National Institutes of Health (NIH) identified a protein known as Pfs47 that allows P falciparum to evade the immune system of Anopheles gambiae. Though mosquitoes typically have some immunity to P falciparum isolates from different continents, the Pfs47 protein may allowisolates of the parasite to adapt to and infect geographically diverse mosquitoes.

NIH scientists said that inhibiting this protein may be key to disrupting transmission and preventing greater global spread of potential malaria vectors.
Nov 23 PNAS study