Severe fever with thrombocytopenia syndrome in China, 2011–17
July 26th, 2018“…..Between April 1, 2011, and Oct 31, 2017, 2096 patients with laboratory-confirmed SFTS were admitted. Mean age at admission was 61·4 years (SD 12·2) and 1239 (59%) patients were female. The case fatality rate (CFR) was 16·2% (95% CI 14·6–17·8). A higher risk was associated with being male (unadjusted odds ratio [OR] 1·45, 95% CI 1·15–1·83; p=0·002), older age (for a 10-year increase, unadjusted OR 1·82, 95% CI 1·62–2·04; p<0·0001), longer delay in admission (for every extra day taken before admission to hospital, unadjusted OR 1·18, 1·12–1·24; p<0·0001), presence of diarrhoea (adjusted OR 1·44, 1·12–1·87; p=0·005) or dyspnoea (adjusted OR 8·35, 5·97–11·69; p<0·0001), and development of haemorrhagic signs (adjusted OR 2·79, 95% CI 2·18–3·57; p<0·0001) or neurological symptoms (adjusted OR 30·26, 21·39–42·81; p<0·0001). Laboratory variables that were associated with death included abnormal concentrations of lactate dehydrogenase, aspartate aminotransferase, and blood urea nitrogen, and abnormal neutrophil percentage, which together with age and neurological symptoms were combined in the clinical scoring system. A total score of more than 8 was the optimal threshold to predict risk of death for patients who were evaluated within 6 days after symptom onset (area under the curve 0·879, 95% CI 0·855–0·902). For all participants, viraemia was a strong predictor of fatal outcome (all p<0·0001). Ribavirin therapy was effective in reducing CFR from 6·25% (15 of 240 participants) to 1·16% (two of 173 participants), but only in patients with a viral load below 1×106 copies per mL (hazard ratio 9·72, 95% CI 1·30–72·87; p=0·027)……”
