Bacterial screening of platelet components by National Health Service Blood and Transplant, an effective risk reduction measure.

BACKGROUND: Bacterial contamination of blood components remains a major cause of sepsis in transfusion medicine. Between 2006 and 2010 in the 5 years before the introduction of bacterial screening of platelet (PLT) components by National Health Service Blood and Transplant (NHSBT), seven cases of PLT component-associated transmission of bacterial infection were recorded for 10 patients, three of which were fatal. STUDY DESIGN AND METHODS: Sampling of individual PLT components was undertaken at 36 to 48 hours after donation and tested in the BacT/ALERT system with 8 mL inoculated into each of aerobic and anaerobic culture bottles. Bottles were incubated until the end of the 7-day shelf life and initial reactive bottles were examined for contamination. Bacterial screened time-expired PLTs were tested as in the screen method. RESULTS: From February 2011 to September 2015, a total of 1,239,029 PLT components were screened. Initial-reactive, confirmed-positive, and false-positive rates were 0.37, 0.03, and 0.19%, respectively. False-negative cultures, all with Staphylococcus aureus, occurred on four occasions; three were visually detected before transfusion and one confirmed transmission resulted in patient morbidity. The NHSBT screening protocol effectively reduced the number of clinically adverse transfusion transmissions by 90% in this reporting period, compared to a similar time period before implementation. Delayed testing of 4515 time-expired PLT units after screening revealed no positives. CONCLUSION: The implementation of bacterial screening of PLT components with the NHSBT BacT/ALERT protocol was an effective risk reduction measure and increased the safety of the blood supply.

The burden of disease and health care use among pertussis cases in school aged children and adults in England and Wales; a patient survey.

BACKGROUND: In 2011-2012 a large pertussis outbreak occurred in England. This provided an opportunity to estimate the disease burden in those aged 5 years and over. As pertussis is likely to be under reported both laboratory-confirmed and non-confirmed cases were included. METHODS: Laboratory-confirmed cases of pertussis, as well as their coughing but non-confirmed household members, were sent a questionnaire that collected information on clinical features and quality of life for the most severe day of disease and the day the patient filled in the questionnaire. The EuroQol-5 dimension questionnaire (EQ-5D) was used to evaluate quality of life. The duration of symptoms was obtained by contacting the patient every two weeks until symptoms stopped. RESULTS: Data for 535 (out of 1262) laboratory confirmed pertussis patients and 44 (out of 140) coughing household contacts was available for analysis. On the most severe day, 56% of laboratory-confirmed cases reported they had 20+ more paroxysms, 58% reported they had a severe cough and 46% reported disruption of sleep for more than 4 hours. For non-confirmed coughing household contacts there were a similar number of coughing spells per day at the height, though the cough was reported to be less severe and to cause less sleep disruption. The main clinical symptoms on the worst day for both were shortness of breath, tiredness, sore ribs and vomiting. The duration of symptoms for both patient groups was around 160 days (162 and 168 days). Under base case assumptions the overall loss of quality of life was 0.097 QALY (0.089-0.106) for confirmed pertussis cases and 0.0365 QALY (0.023-0.054) for coughing household contacts. CONCLUSION: Pertussis is a serious disease in those aged 5 years and over, causing disruption of sleep and daily activities over long period of time. The burden of illness due to undiagnosed pertussis is also considerable.