Cases of Salmonella linked to cucumbers top 800
A multistate outbreak of Salmonella Poona linked to cucumbers imported from Mexico has grown by 71 cases since Oct 14, to 838, the Centers for Disease Control and Prevention (CDC) said today in an update.
In addition, Connecticut and New Hampshire were added to the list of states with cases, bringing the total number of affected states to 38. By far the most cases have occurred in California (232), followed by Arizona (129), Utah (58), Wisconsin (43), and Minnesota (40)—see interactive CDC map.
The pace of reported illnesses has dropped markedly since the outbreak's peak in August and September, but "it has not returned to the number of reported illnesses that we would expect to see (about 5 every month)" if the outbreak were over, the CDC said.
Patients tend to be young, ranging in age from less than 1 year to 99, but with a median age of 18, meaning half are children. Among 601 people with available information, 165 (27%) reported being hospitalized. Arizona, California, Oklahoma, and Texas have each reported an outbreak-related death.
Although the CDC said investigation into the source of the outbreak is ongoing it has identified cucumbers imported from Mexico and distributed by Andrew & Williamson Fresh Produce of San Diego as a likely source of the infections.
Nov 18 CDC update
Study identifies optimal treatment for P knowlesi malaria infections
The first head-to-head trial of two different treatments for the most common type of malaria in Malaysia, also frequently found in other Southeast Asian countries, found that artesunate-mefloquine was highly effective with advantages over chloroquine.
A Malaysian research team reported its findings yesterday in The Lancet Infectious Diseases.
The study is the first randomized control trial to determine the best treatment for malaria caused by the Plasmodium knowlesi parasite. The study took place at three district hospitals between Oct 2012 and Dec 2014 and involved 252 patients older than age 1 with uncomplicated P knowlesi infections.
Patients were randomly assigned to receive one of the two treatments. Researchers looked at parasite clearance parameters 24 hours after patients were treated and also monitored their symptoms and potential side effects.
Parasite and fever clearance were faster with the artesunate-mefloquine group, and anemia risk within 28 days was lower in those patients. In addition, bed occupancy rates were lower in the artesunate-mefloquine group: 2,426 days per 1,000 patients compared to 2,828 per 1,000 for the chloroquine group. One patient in that combo-drug group had a serious neuropsychiatric event that investigators thought was related to the therapy.
They concluded that artesunate-mefloquine is highly effective for uncomplicated P knowlesi malaria infections, with a rapid response that supports unified artemisinin-based combination treatment for all Plasmodium species in endemic areas.
Nov 18 LancetInfect Dis study
Nov 18 Lancet Infect Dis commentary
Hospital study details high rate of C difficile recurrence
A study designed to gauge the burden of recurrent Clostridium difficile infections found that about a third of patients required hospital readmission, about a fourth went on to have severe disease, and 4% developed complications.
The findings from the retrospective cohort study were from a single hospital in Quebec involving 1,527 adults who had infections from Jan 1998 to Dec 2013. Researchers published their findings Nov 17 in Clinical Infectious Diseases.
Investigators found that the probability of an initial recurrent C diff infection was 25%, a second 38%, a third 29%, and a fourth or more 27%. They noted that the risk of the first recurrence fluctuated throughout the study period, but not for subsequent recurrences.
The proportion of severe cases declined with successive infections, as did the risk of complicated C diff infections. The overall pattern showed the severity and complication risk for first recurrent infections declined over time, which was paralleled by increased use of vancomycin.
Researchers concluded that the burden patterns could help guide best treatment strategies. "For novel therapeutic options to be cost-effective, they would need to reduce the risk of first and further recurrences and of hospital readmissions, rather than the risk of complications," they wrote.
Nov 17 Clin Infect Dis abstract
US data show three fourths of kids don't get vaccines at correct times
About 30% of US children have not received all doses of the six recommended vaccines by age 2, and 74% did not receive the recommended doses on time, according to a study yesterday in Vaccine.
US researchers analyzed data from the 2012 National Immunization Survey on 11,710 children aged 24 to 35 months and also conducted a state-specific examination of vaccine completion.
They found that about 70% of kids completed all doses of the six vaccines by age 2, with completion rates varying from 68% for rotavirus to 92% for polio vaccine. Only 26%, however, received all the vaccine doses as scheduled. Of the 74% who received at least one late dose, 39% had 7 months or more of undervaccination.
The authors concluded that, although completion of individual vaccines approached Healthy People 2020 targets, the vaccination gaps warrant additional interventions to increase vaccine receipt.
Nov 18 Vaccine study
Dengue fever cases in Hawaii increase by 23, to 79
The Hawaii Department of Health (HDOH) said today that the number of locally acquired cases of dengue fever on the big island of Hawaii has increased by 23 in 3 days, to 79.
Of the confirmed cases of the mosquito-borne disease, 68 are in Hawaii residents and 11 are in visitors. Illness-onset dates range from Sep 11 to Nov 11. Five of the new cases involve children, raising that total to 20. The 59 other cases involve adults.
The agency yesterday updated a map that shows eight potential areas of infection on the island, including two areas said to be high risk. Officials are monitoring for dengue on all of the Hawaiian islands.
The HDOH said, "Dengue is not endemic to Hawaii. However, it is intermittently imported from endemic areas by infected travelers. This is the first cluster of locally-acquired dengue fever since the 2011 outbreak on Oahu."
Nov 19 HDOH update
Nov 17 CIDRAP News scan on previous update