Efficient inactivation of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in human apheresis platelet concentrates with amotosalen and ultraviolet A light.

OBJECTIVES: The detection of SARS-CoV-2 RNA in blood and platelet concentrates from asymptomatic donors, and the detection of viral particles on the surface and inside platelets during in vitro experiments, raised concerns over the potential risk for transfusion-transmitted-infection (TTI). The objective of this study was to assess the efficacy of the amotosalen/UVA pathogen reduction technology for SARS-CoV-2 in human platelet concentrates to mitigate such potential risk. MATERIAL AND METHODS: Five apheresis platelet units in 100% plasma were spiked with a clinical SARS-CoV-2 isolate followed by treatment with amotosalen/UVA (INTERCEPT Blood System), pre- and posttreatment samples were collected as well as untreated positive and negative controls. The infectious viral titer was assessed by plaque assay and the genomic titer by quantitative RT-PCR. To exclude the presence of infectious particles post-pathogen reduction treatment below the limit of detection, three consecutive rounds of passaging on permissive cell lines were conducted. RESULTS: SARS-CoV-2 in platelet concentrates was inactivated with amotosalen/UVA below the limit of detection with a mean log reduction of>3.31±0.23. During three consecutive rounds of passaging, no viral replication was detected. Pathogen reduction treatment also inhibited nucleic acid detection with a log reduction of>4.46±0.51 PFU equivalents. CONCLUSION: SARS-CoV-2 was efficiently inactivated in platelet concentrates by amotosalen/UVA treatment. These results are in line with previous inactivation data for SARS-CoV-2 in plasma as well as MERS-CoV and SARS-CoV-1 in platelets and plasma, demonstrating efficient inactivation of human coronaviruses.

Amotosalen and ultraviolet A light efficiently inactivate MERS-coronavirus in human platelet concentrates.

OBJECTIVE: This study aimed to assess the efficacy of the INTERCEPT™ Blood System [amotosalen/ultraviolet A (UVA) light] to reduce the risk of Middle East respiratory syndrome-Coronavirus (MERS-CoV) transmission by human platelet concentrates. BACKGROUND: Since 2012, more than 2425 MERS-CoV human cases have been reported in 27 countries. The infection causes acute respiratory disease, which was responsible for 838 deaths in these countries, mainly in Saudi Arabia. Viral genomic RNA was detected in whole blood, serum and plasma of infected patients, raising concerns of the safety of blood supplies, especially in endemic areas. METHODS: Four apheresis platelet units in 100% plasma were inoculated with a clinical MERS-CoV isolate. Spiked units were then treated with amotosalen/UVA to inactivate MERS-CoV. Infectious and genomic viral titres were quantified by plaque assay and quantitative real-time reverse transcription polymerase chain reaction (RT-qPCR). Inactivated samples were successively passaged thrice on Vero E6 cells to exclude the presence of residual replication-competent viral particles in inactivated platelets. RESULTS: Complete inactivation of MERS-CoV in spiked platelet units was achieved by treatment with Amotosalen/UVA light with a mean log reduction of 4·48 ± 0·3. Passaging of the inactivated samples in Vero E6 showed no viral replication even after nine days of incubation and three passages. Viral genomic RNA titration in inactivated samples showed titres comparable to those in pre-treatment samples. CONCLUSION: Amotosalen and UVA light treatment of MERS-CoV-spiked platelet concentrates efficiently and completely inactivated MERS-CoV infectivity (>4 logs), suggesting that such treatment could minimise the risk of transfusion-related MERS-CoV transmission.

First complete genome sequence of circulating dengue virus serotype 3 in Jeddah, Saudi Arabia.

Here we report the first full-length genome sequence of dengue virus serotype 3 (DENV-3) from a strain isolated from a patient in Jeddah, Saudi Arabia, in 2014. The genome consists of 10 635 bp and shows close similarity to circulating genotype III isolates from Singapore, suggesting possible importation, most probably during religious pilgrimages to Saudi Arabia.

Characterisation of aflatoxin and deoxynivalenol exposure among pregnant Egyptian women.

Mycotoxins such as the aflatoxins and deoxynivalenol (DON) are frequent contaminants of food. Aflatoxin B1 (AFB1) and DON affect the immune system and restrict growth; additionally AFB1 is carcinogenic. To date there are limited descriptive biomarker data concerning maternal exposures during pregnancy, and none on co-exposures to these mycotoxins. This survey was a cross-sectional assessment providing descriptive data on the concentrations of serum aflatoxin-albumin (AF-alb), urinary aflatoxin M1 (AFM1), and urinary DON for 98 pregnant women from Egypt, in relation to diet and socioeconomic status, during the third trimester. AF-alb was detected in 34 of 98 (35%) samples, geometric mean (GM) of positives = 4.9 pg AF-lys mg(-1) albumin (95% confidence interval (CI) = 4.1-5.8 pg mg(-1)), and AFM1 in 44 of 93 (48%) samples, GM of positives = 19.7 pg mg(-1) creatinine (95%CI = 14.8-26.3 pg mg(-1)). AF-alb and AFM1 levels were positively correlated (R = 0.276, p = 0.007). DON was detected in 63 of 93 (68%), GM of positives = 2.8 ng mg(-1) (95%CI = 2.1-3.6 ng mg(-1)). Aflatoxin and DON biomarkers were observed in 41% of the subjects concurrently. The frequency and level of these biomarkers in Egyptian women were modest compared with known high-risk countries. However, this study represents the first biomarker survey to report on the occurrence of DON biomarkers in an African population, in addition to the co-occurrence of these two potent mycotoxins. This combined exposure may be of particular concern during pregnancy given the potential of toxin transfer to the foetus.

Higher clearance of hepatitis C virus infection in females compared with males.

BACKGROUND AND AIMS: According to the literature, 14-46% of subjects clear hepatitis C virus (HCV) from blood after infection. Controversy exists about sex differences in HCV clearance rates. PATIENTS AND METHODS: We compared HCV clearance in males and females using data from a large population based study on HCV infection in Egypt. Definitions used in the paper were: cleared HCV infection (positive HCV antibody and negative HCV RNA test results) and chronic HCV infection (positive HCV antibody and positive HCV RNA test results). The study sample included 4720 village residents aged 18-65 years recruited through home based visits (n = 2425) or voluntary screening (n = 2295). RESULTS: Overall, HCV antibody prevalence was 910/4720 (19.3% (95% confidence interval 18.2-20.4)). Of those with HCV antibodies (n = 910), 61.5% had chronic HCV infection. Compared with males, females were more likely to have cleared the virus (44.6% v 33.7%, respectively; p = 0.001). Control for age, schistosomiasis history, iatrogenic exposures, and sexual exposure to HCV did not alter the positive association between female sex and viral clearance. CONCLUSION: This study provides strong evidence in favour of a higher HCV clearance rate in females compared with males.