Use of BioPortal in a PRRSV outbreak in a Spanish farm

• 10 minutes
• Expertise article
• A.Finestra, E.Galíndez, I.Hernández, E.Sánchez, V.Rodríguez, S.Figueras, G.Abella

A.Finestra¹, E.Galíndez², I.Hernández³, E.Sánchez³, V.Rodríguez³, S.Figueras³, G.Abella³

¹Finestra Veterinarian Advisors, SL; ²Pig Production Co. Spain; ³Boehringer Ingelheim Animal Health España S.A.U.

Introduction

Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is one of the leading swine pathogens1. The availability of sequence data from PRRSV from widespread geographic territories has enabled a better understanding of the fight against PRRS.

The sequences do not provide any information unless we compare then within a farm, a company or at a region level. During the last 9 years, Boehringer Ingelheim Vetmedica, Inc. (BIVI) in collaboration with UC Davis -and other institutions such as Iowa State University- have improved the program Disease Bioportal software to the particularities of PRRSV. BioPortal is a web-based system that can manage real time or near-to-real time a huge amount of data. Tools are available for spatio-temporal display, graphics, and phylogenetic analysis of the data. New introduction of isolates and the evolving dynamics of the virus can be monitored by the consistent sequence of the diagnosis. Thus, the aim of this work was to monitor the genetic changes at a farm level by using Bioportal.

Materials and Methods

The study was conducted in a 1200 sows farrow-to- wean farm located in the north-east of Spain. The farm was under a PRRS 5 step process control since August 2015. Since then, the farm has been implementing 3 sow mass vaccination per year and the piglets have been receiving a dose of Ingelvac PRRSFLEX EU before weaning. Thirty piglets were bled at weaning every two months. The constant monitoring program has allowed detecting 2 different strains since its beginning. During 2016 and 2017, we detected a resident strain (strain A), and since July 2019 we were able to detect a new strain (strain FAST). Bioportal software (http://bioportal.ucdavis.edu/) was used to understand if there was any issue of internal or external biosecurity. We assumed that sequences are different when the heterology within the 606 nucleotides of the ORF5 is higher than 3%. (Figure 1)

Figure 1: Simulation and phylogenetic chart, representing the sequences obtained in the farm since 2015.

In order to evaluate the impact of the introduction of a new strain in to the system several KPI were analyzed. The data were extracted from the PigCHAMP program. Two periods of time were analyzed, period before the introduction of the new strain FAST (July’18-June’19) and period after (July’19-Sep’19).

Results

Analyzing this information with the veterinarian in charge of the farm, we were able to find out that strain FAST was highly prevalent in that area since 2016, specifically it has been detected in 72 different farms of 18 different companies.

When comparing the productive results before and after the detection of the strain FAST, no differences have been detected. In this case the introduction of a new strain into the system has only affected the productive parameters in weaned piglets. The main KPI remain stable in sows. (Table 1).

Table 1: Comparison of the KPI average for the different periods.

Conclusions and Discussion

Bioportal was a crucial tool to easily track a newly introduced PRRSv sequence in a farm by making comparisons within a huge sequence data base. The main conclusion is that external biosecurity is a very important risk factor for PRRSv dissemination through different areas and production systems. Special attention must be given to external biosecurity in high-density areas.

References

1. E. Mateu et, al; Virus research 2006