We evaluated the effect of sustained virologic response (SVR) from direct‐acting antiviral (DAA)‐ and interferon‐based treatments on hepatocellular carcinoma (HCC) risk in a large population‐based cohort in Canada. We used data from the BC Hepatitis Testers Cohort, which includes ~1.3 million individuals tested for HCV since 1990, linked with healthcare administrative and registry datasets. Patients were followed from the end of HCV treatment to HCC, death or 31 December 2016. We assessed HCC risk among those who did and did not achieve SVR by treatment type using proportional hazard models. Of 12 776 eligible individuals, 3905 received DAAs while 8871 received interferon‐based treatments, followed for a median of 1.0 [range: 0.6‐2.7] and 7.9 [range: 4.4‐17.1] years, respectively. A total of 3613 and 6575 achieved SVR with DAAs‐ and interferon‐based treatments, respectively. Among DAAs‐treated patients, HCC incidence rate was 6.9 (95%CI: 4.7‐10.1)/1000 person yr (PY) in SVR group (HCC cases: 26) and 38.2 (95%CI: 20.6‐71.0) in the no‐SVR group (HCC cases: 10, P < .001). Among interferon‐treated individuals, HCC incidence rate was 1.8 (95%CI: 1.5‐2.2) in the SVR (HCC cases: 99) and 13.9 (95%CI: 12.3‐15.8) in the no‐SVR group (HCC cases: 239, P < .001). Compared with no‐SVR from interferon, SVR from DAA‐ and interferon‐based treatments resulted in significant reduction in HCC risk (adjusted subdistribution hazard ratio (adjSHR) DAA = 0.30, 95%CI: 0.19‐0.48 and adjSHR interferon = 0.2, 95%CI: 0.16‐0.26). Among those with SVR, treatment with DAAs compared to interferon was not associated with HCC risk (adjSHR = 0.93, 95%CI: 0.51‐1.71). In conclusion, similar to interferon era, DAA‐related SVR is associated with 70% reduction in HCC risk.

Influenza vaccine effectiveness (IVE) varies over different influenza seasons and virus (sub)types/lineages. To assess the association between IVE and circulating influenza virus (sub)types/lineages, we estimated the overall and (sub)type specific IVE in the Netherlands. We conducted a test-negative case control study among subjects with influenza-like illness or acute respiratory tract infection consulting the Sentinel Practices over 11 influenza seasons (2003/2004 through 2013/2014) in the Netherlands. The adjusted IVE was estimated using generalized linear mixed modelling and multiple logistic regression. In seven seasons vaccine strains did not match the circulating viruses. Overall adjusted IVE was 40% (95% CI 18 to 56%) and 20% (95% CI -5 to 38%) when vaccine (partially)matched and mismatched the circulating viruses, respectively. When A(H3N2) was the predominant virus, IVE was 38% (95% CI 14 to 55%). IVE against infection with former seasonal A(H1N1) virus was 83% (95% CI 52 to 94%), and with B virus 67% (95% CI 55 to 76%). In conclusion IVE estimates were particularly low when vaccine mismatched the circulating viruses and A(H3N2) was the predominant influenza virus subtype. Tremendous effort is required to improve vaccine production procedure and to explore the factors that influence the IVE against A(H3N2) virus.

Background: Tattoos may cause a variety of adverse reactions in the body, including immune reactions and infections. However, it is unknown whether tattoos may increase the risk of lymphatic cancers such as non-Hodgkin lymphoma (NHL) and multiple myeloma. Methods: Participants from two population-based case–control studies were included in logistic regression models to examine the association between tattoos and risk of NHL and multiple myeloma. Results: A total of 1,518 participants from the NHL study (737 cases) and 742 participants from the multiple myeloma study (373 cases) were included in the analyses. No statistically significant associations were found between tattoos and risk of NHL or multiple myeloma after adjusting for age, sex, ethnicity, education, body mass index, and family history. Conclusions: We did not identify any significant associations between tattoos and risk of multiple myeloma, NHL, or NHL subtypes in these studies. Impact: Though biologically plausible, tattoos were not associated with increased risk of NHL or multiple myeloma in this study. Future studies with greater detail regarding tattoo exposure may provide further insights.