Capture-recapture and anti-tuberculosis drug prescriptions, Balearic Islands, Spain, 2010-2012.

SETTING: Tuberculosis (TB) control requires accurate knowledge of TB incidence, but few studies have been published on TB incidence using individual data from drug prescriptions. OBJECTIVE: To measure the estimated completeness of regional surveillance system data before and after adding data from anti-tuberculosis drug prescriptions. DESIGN: We compiled data on all individuals who received specific anti-tuberculosis drugs from three sources-the passive surveillance system, the active surveillance system and the anti-tuberculosis drug prescription database-in the Balearic Islands, Spain, between 2010 and 2012. We applied the capture-recapture method to measure completeness of data reporting. Statistical significance was set at P < 0.05, and 95% confidence intervals (CIs) were calculated. RESULTS: We detected 605 incident cases, compared with an estimated incidence of 719 cases (95%CI 646-793), representing 84.1% data completeness. We detected 480 of an estimated 559 pulmonary TB cases (95%CI 501-617; 85.9% data completeness) and 125 of an estimated 161 extra-pulmonary TB cases (95%CI 113-211; 77.6% data completeness). CONCLUSIONS: By adding a new source, we increased detection with respect to a previous study by 10.4% for all forms of TB, 9.7% for pulmonary TB and 13% for extra-pulmonary TB.

Estimated incidence of tuberculosis by capture-recapture in the Balearic Islands, 2010-2012.

SETTING: The Balearic Islands, Spain, 2010-2012. OBJECTIVE: To assess the completeness of TB surveillance, and to examine observed and estimated incidence rates (IR) compared with the period 2005-2007. DESIGN: The completeness of TB surveillance was assessed using the capture-recapture method. Confidence intervals were calculated using log-linear models. Data sources were records of mandatory notifiable diseases, active hospital surveillance and computerised primary health care history. RESULTS: Surveillance completeness for respiratory TB (R-TB) was 99.5%; it was 100% for non-respiratory TB (NR-TB). The overall observed IR was 16.32 cases/100 000 for all types of TB, 3.4 for NR-TB and 12.9 for R-TB. The estimated IR of TB all forms was 16.35/100 000 (95%CI 16.26-16.53), for NR-TB it was 3.4/100 000 (95%CI not calculated) and for R-TB it was 13.0/100 000 (95%CI 12.85-13.12). Surveillance completeness for R-TB during the period 2005-2007 was 65.2%; the observed IR was 22.6/100 000 and the estimated IR 31.3/10 000 (95%CI 25.0-37.7). CONCLUSION: The similarity of observed and estimated IR during the period 2010-2012 indicates the validity of the surveillance and the use of improved systems such as electronic medical records in recent years.

Epidemiology and molecular investigation of hepatitis C infection following holiday haemodialysis.

BACKGROUND: Hepatitis C virus infection (HCV) is not infrequent among haemodialysis patients. Most published reports suggest that patient-to-patient spread, either directly or indirectly, is the most common mode of transmission in renal units. AIM: To investigate the source of an outbreak, and the route of transmission, of acute HCV infection in two Scottish patients occurring within eight weeks of receiving haemodialysis in the same unit while on holiday in Majorca. METHODS: This was an international epidemiological and molecular investigation of HCV infection among a cohort of haemodialysis patients from nine countries. FINDINGS: No further HCV-positive infections were observed among residents and holidaymakers receiving haemodialysis at the unit in Majorca. Molecular investigations confirmed that a Spanish healthcare worker (HCW) was the source of infection for the two Scottish patients. The investigators were unable to determine the route of transmission. CONCLUSIONS: This outbreak is the first reported case of HCW-to-patient transmission of HCV in a renal unit, and the third reported case of transmission involving a HCW who had not performed invasive procedures. The issue of whether renal units are an exceptional case with regards to the risk of transmission associated with non-invasive procedures should be considered, in conjunction with the need to improve surveillance of blood-borne virus transmissions in renal units in the UK and abroad.