Detection of PRRSV RFLP type 1-7-4 over time

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

This week, Dr. Mariana Kikuti from the MSHMP team shares information about the PRRS RFLP type 1-7-4 prevalence in the MSHMP data.

Key Points

  • PRRSV RFLP type 1-7-4 was first identified in our MSHMP dataset in 2003.
  • An increasing trend up to 2014 has been observed and is now on a decreasing trend.
Continue reading “Detection of PRRSV RFLP type 1-7-4 over time”

MSHMP PRRS Prevalence Chart Description

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

Today, the MSHMP team is explaining the interpretation of Chart 2 of their weekly report. If you missed Chart 1 last week, you may find it here.

Key points

  • The prevalence chart (Chart 2) describes the percentage of herds that are classified in a given status through time.
  • It allows eyeballing general trends although the growing nature of the project does not allow year to year comparisons without proper adjustment.
  • For PRRSv, there is a steady increase in the percentage of herds in status 1 in recent years. PRRSv
Continue reading “MSHMP PRRS Prevalence Chart Description”

Effect of strain-specific maternally-derived antibodies on influenza A virus infection dynamics in nursery pigs

A new scientific article from the Torremorell lab, about the influence of maternal antibodies on influenza dynamics was published in PLoS ONE.

The study followed 10 cohorts of nursery piglets form a single influenza-positive sow farm and compared influenza dynamics based on the vaccination status of the dam.

Continue reading “Effect of strain-specific maternally-derived antibodies on influenza A virus infection dynamics in nursery pigs”

Science Page: Herd-level prevalence and incidence of porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus(PDCoV) in swine herds in Ontario, Canada

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

This week, we are sharing a report regarding the prevalence of Porcine Deltacoronavirus and Porcine Epidemic Diarrhea virus in swine herds from Ontario.

Key Points

  • Cumulative incidence of PED and PDCoV in Canada is decreasing according to data coming from the industry for the year 2014, 2015 and 2016.
  • PED showed a cyclical pattern when looking at the number of farms infected. However, PDCoV showed a more erratic pattern with no clear trends.
  • Industry driven disease control programs provide useful information to understand temporal evolution and disease patterns.

The primary goal of this study was to estimate herd-level incidence and prevalence measures for PEDV and PDCoV in swine herds in Ontario (Canada) between January 2014 and December 2016, based on industry data (Ontario Swine Health Advisory Board (OSHAB) Disease Control Program (DCP)).

The full paper was published in the Transboundary and Emerging Diseases journal.

Ajayi PED Deltacoronavirus prevalence in swine herd Ontario

Herd-level incidence risk and rate of two novel porcine coronaviruses (PEDV and PDCoV) in Ontario swine herds between 2014 and 2016, and estimated prevalence of positive cases at the end of each year based on data provided in the Ontario Swine Health Advisory Board (OSHAB) Disease Control Program (DCP) database (average number of herds for 2014–2016 = 1093).

PED showed a cyclical pattern over the three years of the study while PDCoV showed a more erratic pattern. Incidence decreased over time between 2014 and 2016 in both, PED and PDCoV.

You can also read our report on the prevalence of PDCoV in the USA.

Science Page: Influenza herd-level prevalence and seasonality in Midwestern sow farms

This is our Friday rubric: every week a new Science Page from the Bob Morrison’s Swine Health Monitoring Project. The previous editions of the science page are available on our website.

This week, we are sharing a report from Dr. Fabian Chamba regarding influenza herd-level prevalence and seasonality in the Midwest.

Key points:

  • Influenza is endemic and seasonal in piglets from sow farms in the Midwest with higher infections in winter and spring.
  • Influenza seasonality was partially explained by outdoor air absolute humidity and temperature trends.
  • Influenza genetic diversity was high and co-circulation of more than one genetically distinct virus was common.

To study influenza levels over time and its seasonality, monthly testing data of piglets at weaning from 34 sow farms during ~5 years were analyzed.

There were 28% of positive submissions with a median influenza herd-level prevalence of 28%. Genetic diversity was significant with 10 genetically distinct clades of contemporary US swine influenza viruses as shown below. Furthermore, 21% of farms had 3 genetically distinct viruses circulating over time; 18% had 2, 41% had 1 and 20% had no isolates available.

In summary, influenza herd-level prevalence in Midwestern sow farms had a seasonal pattern with higher levels in winter and spring. This is important to better allocate influenza control strategies such as vaccination in sow farms. Influenza seasonality was partially explained by outdoor air absolute humidity and temperature although other factors such as immunity and new introductions may play a role in the observed seasonality.

Read the full story at https://www.frontiersin.org/articles/10.3389/fvets.2017.00167/full.