Evaluation of the Efficacy of Commercial Disinfectants against African Swine Fever Virus.

African swine fever (ASF) is an economically important disease due to high morbidity and mortality rates and the ability to affect all ages and breeds of pigs. Biosecurity measures to prevent the spread of the causative agent, African swine fever virus (ASFV), include prescriptive cleaning and disinfection procedures. The aim of this study was to establish the biocidal effects of twenty-four commercially available disinfectants including oxidizing agents, acids, aldehydes, formic acids, phenol, and mixed-class chemistries against ASFV. The products were prepared according to the manufacturer's instructions and a suspension assay was performed with ASFV strain, BA71V using Vero cells (African green monkey cells) to test efficacy in reducing ASFV infection of cells. Generally, disinfectants containing formic acid and phenolic compounds, as well as oxidizing agents reduced viral titers of ASFV by over 4 log10 at temperatures ranging from 4 °C to 20 °C. Hydrogen peroxide, aldehyde, and quaternary ammonium compounds containing disinfectants were cytotoxic, limiting the detection of viral infectivity reductions to less than 4 log10. These preliminary results can be used to target research on disinfectants which contain active ingredients with known efficacy against ASFV under conditions recommended for the country where their use will be applied.

Towards a Sampling Rationale for African Swine Fever Virus Detection in Pork Products.

African swine fever (ASF) is a highly lethal disease of pigs caused by the ASF virus (ASFV), which presents a serious threat to global food security. The movement of contaminated pork products has previously been postulated as contributing to the introduction of ASF into new areas. To evaluate the performance of ASFV detection systems in multi-component pork products, we spiked sausage meat with four different ASFV-containing materials (ASFV cell culture, pork loin, meat juice and bone marrow). DNA was extracted using two manual systems (MagMAX CORE, Qiagen) and one automated (MagMAX CORE) one, and three qPCR assays (VetMAX, King, UPL) were used. The performance of the DNA extraction systems was as follows; automated MagMAX > manual MagMAX > manual Qiagen. The commercial VetMAX qPCR assay yielded significantly lower CT values (p < 0.001), showing greater sensitivity than the World Organization for Animal Health (OIE)-prescribed assays (King, UPL). Detection probability was the highest for matrices contaminated with bone marrow compared with pork loin or meat juice. An estimated minimum sample size of one 1-g sample is sufficient to detect ASFV in a homogenous pork product if bone marrow from infected pigs comprises 1 part in 10,000. We demonstrated that existing ASFV detection systems are appropriate for use in a food-testing capacity, which can provide an additional control measure for ASF.

The splicing of tiny introns of Paramecium is controlled by MAGO.

The exon junction complex (EJC) is a key element of the splicing machinery. The EJC core is composed of eIF4A3, MAGO, Y14 and MLN51. Few accessory proteins, such as CWC22 or UPF3, bind transiently to the EJC. The EJC has been implicated in the control of the splicing of long introns. To ascertain whether the EJC controls the splicing of short introns, we used Paramecium tetraurelia as a model organism, since it has thousands of very tiny introns. To elucidate whether EJC affects intron splicing in P. tetraurelia, we searched for EJC protein-coding genes, and silenced those genes coding for eIF4A3, MAGO and CWC22. We found that P. tetraurelia likely assembles an active EJC with only three of the core proteins, since MLN51 is lacking. Silencing of eIF4A3 or CWC22 genes, but not that of MAGO, caused lethality. Silencing of the MAGO gene caused either an increase, decrease, or no change in intron retention levels of some intron-containing mRNAs used as reporters. We suggest that a fine-tuning expression of EJC genes is required for steady intron removal in P. tetraurelia. Taking into consideration our results and those published by others, we conclude that the EJC controls splicing independently of the intron size.