An exploration of the disease burden due to Cryptosporidium in consumed surface water for sub-Saharan Africa

The protozoan pathogen Cryptosporidium is an important cause of diarrhoeal disease, but in many contexts its burden remains uncertain. The Global Waterborne Pathogen model for Cryptosporidium (GloWPa-Crypto) predicts oocyst concentrations in surface water at 0.5 by 0.5° (longitude by latitude) resolution, allowing us to assess the burden specifically associated with the consumption of contaminated surface water at a large scale. In this study, data produced by the GloWPa-Crypto model were used in a quantitative microbial risk assessment (QMRA) for sub-Saharan Africa, one of the regions most severely affected by diarrhoeal disease. We first estimated the number of people consuming surface water in this region and assessed both direct consumption and consumption from a piped (treated) supply. The disease burden was expressed in disability adjusted life years (DALYs). We estimate an annual number of 4.3 × 10⁷ (95% uncertainty interval [UI] 7.4 × 10⁶–5.4 × 10⁷) cases which represent 1.6 × 10⁶ (95% UI 3.2 × 10⁵–2.3 × 10⁶) DALYs. Relative disease burden (DALYs per 100,000 persons) varies widely, ranging between 1.3 (95% UI 0.1–5.7) for Senegal and 1.0 × 10³ (95% UI 4.2 × 10²–1.4 × 10³) for Eswatini. Countries that carry the highest relative disease burden are primarily located in south and south-east sub-Saharan Africa and are characterised by a relatively high HIV/AIDS prevalence. Direct surface water consumption accounts for the vast majority of cases, but the results also point towards the importance of stable drinking water treatment performance. This is, to our knowledge, the first study to utilise modelled data on pathogen concentrations in a large scale QMRA. It demonstrates the potential value of such data in epidemiological research, particularly regarding disease aetiology.     

Severe Obesity Increases Risk of Infection After Revision Total Hip Arthroplasty

BackgroundThe increasing prevalence of obesity has resulted in an increased number of revision total hip arthroplasties (rTHAs) performed in patients with a high body mass index (BMI). The aim of this study is to evaluate whether obesity negatively affects (1) complication rate, (2) reoperation and revision rate, and (3) patient-reported outcome in rTHA.MethodsIn this registry-based study, we prospectively followed 444 rTHAs (cup: n = 265, stem: n = 57, both: n = 122) performed in a specialized high-volume orthopedic center between 2013 and 2015. The number of complications, and reoperation and revision surgery was registered until 5 years postoperatively. Oxford Hip Score (OHS) was evaluated preoperatively, and at 1 and 2 years postoperatively. Patients were categorized based on BMI to nonobese (<30 kg/m², n = 328), obese (30-35 kg/m², n = 82), and severe obese (≥35 kg/m², n = 34).ResultsSevere obese patients, but not obese patients, had higher risks of complications and re-revision than nonobese patients. In particular, the risk of infection following rTHA was higher in severe obese patients (24%) compared to nonobese patients (3%; relative risk, 7.7). Severe obese patients had overall poorer OHS than nonobese patients, but improvement in OHS did not differ between severe obese and nonobese patients. No differences between obese and nonobese groups on OHS were observed.ConclusionIn our study, severe obesity was associated with an increased risk of infection following rTHA. Patients with high BMI should be counseled appropriately before surgery.