The 2015–2016 influenza epidemic in Beijing,China: Unlike elsewhere,circulation of influenza A(H3N2) with moderate vaccine effectiveness

BackgroundWhile the 2015–2016 influenza season in the northern hemisphere was dominated by A(H1N1)pdm09 and B/Victoria viruses, in Beijing, China, there was also significant circulation of influenza A(H3N2) virus. In this report we estimate vaccine effectiveness (VE) against influenza A(H3N2) and other circulating viruses, and describe further characteristics of the 2015–2016 influenza season in Beijing.MethodsWe estimated VE of the 2015–2016 trivalent inactivated vaccine (TIV) against laboratory-confirmed influenza virus infection using the test-negative study design. The effect of prior vaccination on current VE was also examined.ResultsOf 11,000 eligible patients included in the study, 2969 (27.0%) were influenza positive. Vaccination coverage was 4.2% in both cases and controls. Adjusted VE against all influenza was 8% (95% CI: −16% to 27%): 18% (95% CI: −38% to 52%) for influenza A(H1N1)pdm09, 54% (95% CI: 16% to 74%) for influenza A(H3N2), and −8% (95% CI: −40% to 18%) for influenza B/Victoria. The overall VE for receipt of 2015–2016 vaccination only, 2014–2015 vaccination only, and vaccinations in both seasons was −15% (95% CI: −63% to 19%), −25% (95% CI: −78% to 13%), and 18% (95% CI: −11% to 40%), respectively.ConclusionsOverall the 2015–2016 TIV was protective against influenza infection in Beijing, with higher VE against the A(H3N2) viruses compared to A(H1N1)pdm09 and B viruses.     

Blood harmane (1-methyl-9H-pyrido[3,4-b]indole) concentration in dystonia cases vs. controls

BackgroundHarmane (1-methyl-9H-pyrido[3,4-b]indole) (HA) is a potent neurotoxin that has been linked to two neurological diseases, essential tremor and Parkinson's disease. Blood harmane concentrations [HA] are elevated in patients with both diseases. An important question is whether HA is specifically linked with these diseases or alternatively, is a non-specific marker of neurological illness.ObjectivesWe assessed whether blood [HA] was elevated in patients with a third neurological disease, dystonia, comparing them to controls.MethodsBlood [HA] was quantified by high performance liquid chromatography. Subjects comprised 104 dystonia cases and 107 controls.ResultsMean log blood [HA] in dystonia cases was similar to that of controls (0.41 ± 0.51 g⁻¹⁰/ml vs. 0.38 ± 0.61 g⁻¹⁰/ml, t = 0.42, p = 0.68). In unadjusted and adjusted logistic regression analyses, log blood [HA] was not associated with the outcome (diagnosis of dystonia vs. control): odds ratio (OR)_unadjusted = 1.11, 95% confidence interval (CI) = 0.69–1.79, p = 0.68; OR_adjusted = 1.07, 95% CI = 0.58–1.97, p = 0.84.ConclusionsIn contrast to the elevated blood [HA] that has been reported in patients with essential tremor and Parkinson's disease, our data demonstrate that blood [HA] was similar in patients with dystonia and controls. These findings provide the first support for the notion that an elevated blood [HA] is not a broad feature of neurological disease, and may be a specific feature of certain tremor disorders.     

A big pertussis outbreak in a primary school with high vaccination coverage in northern China: An evidence of the emerging of the disease in China

BackgroundA big pertussis outbreak occurred in a primary school with high vaccination coverage in northern China. An investigation was carried out in order to calculate the attack rate and identify the risk factors.MethodsBetween May 12 and July 29, an investigation was carried out in the primary school, which included 383 students and 27 teachers. Three definitions were used to distinguish the cases: confirmed, epidemiologically linked and suspected cases. A total of 232 blood samples were collected and examined by ELISA among healthy children in another primary school.ResultsA total of 138 suspected pertussis cases were counted, of which 116 students were confirmed. The attack rate among students was as high as 30.29%. The pertussis outbreak lasted 88 days, and had quaternary cases of transmission. Migrant children were almost four times as likely to catch the disease as local children (p = 0.005). In addition, students who had received the last dose of pertussis vaccine more than 4 years prior were three times more likely of becoming ill than those less than 4 years (p = 0.006). The average level of antibodies to pertussis was 30.99 IU/mL among healthy children. No statistically significant difference was observed between DTaP and DTwP (p = 0.843).ConclusionsThis pertussis outbreak in a primary school with high vaccination coverage was an evidence of the pertussis resurgence in China. The major risk factor we identified was the waning of immunity in the years after pertussis vaccination. Booster vaccination for students should be given.     

A survey of variable selection methods in two Chinese epidemiology journals

Background  

Although much has been written on developing better procedures for variable selection, there is little research on how it is practiced in actual studies. This review surveys the variable selection methods reported in two high-ranking Chinese epidemiology journals.     

Genotoxicity and sub-chronic toxicity of MYOLUTION® (branched chain keto acids)

MYOLUTION^®, which consists of a mixture of the branched chain keto acids, keto-leucine, keto-isoleucine and keto-valine, as their calcium salts, may potentially be used as a food ingredient based on the reported contributions of these compounds to muscle health and exercise performance. Tests on genotoxicity and sub-chronic toxicity were performed to evaluate the safety of branched chain keto acids. No genotoxic effects were observed in the bacterial mutation assay or the in vitro micronucleus assay in human lymphocytes. In the 28 day and 90 day repeated dose toxicity studies no test item related mortality or toxicological effects on clinical signs, body weight, food consumption, urine parameters, hematology, clinical biochemistry parameters, organ weight, gross pathological findings and histopathology were observed. Based on the studies described here, MYOLUTION^® does not exert a genotoxic effect, and a no-observed-adverse-effect-level of 3318.38 mg/kg bw/day in males and 3733.28 mg/kg bw/day in females was determined in the 90 day repeated dose toxicity study.