Science page: Are patterns of spatiotemporal clustering of PRRSv consistent across years?

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 studied a subset of MSHMP participants located in the Midwest to test if some location/time combinations are more prominent during certain seasons across the years. Data from 358 farms in 10 management systems from 2011 to 2015 was compiled to look for clusters.

The clusters found by the SaTScanTM software are represented below. The red circles represent clusters identified in the time period from January to June, whereas blue ones are July to December. We can note that clusters were identified every year but that they varied with time.

Significant PRRS spatial cluster midwest
Significant spatial clusters for PRRSV in the Midwest between 2011 and 2015.

Key points

  • PRRS cases are recognized to be seasonal and aggregated by geographical space.
  • However, spatiotemporal patterns of PRRS clustering were not consistent across years.
  • Drivers of infection spread may vary over the years.

Future uses for this model can be found in the entire report

Science Page: Are the farms that broke with PED the same?

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 proud to introduce a new chart in the Morrison’s Swine Health Monitoring Project. This new addition will be able to answer a common question regarding PEDV outbreaks:

Are the farms currently breaking with PEDV the same than the ones which broke in the past?

To interpret the figure, follows these steps.

  • Horizontal axis represents all the farms that borke with PEDV during the season 2016/2017, with each tick representing an individual farm
  • Vertical axis shows the previous seasons with 2016-2017 on top and 2012-2013 at the very bottom.
  • The color of the cell (year : farm) represents the number of outbreaks experienced; darker blue meaning more outbreaks.

Here is the example of this chart presented this week:

MSHMP PEDV chart
Outbreak history of farms that broke during the 2016-2017 season.

Key points:

The farms that break with PEDV do not appear to have a history of PEDV infections in the prior season.

Of the farms that broke during the 2016/17 season, only 5 (6.5%) of them had outbreaks during the previous season and 43 (56.6%) of them had broken at some point since 2013.

Only one farm has had an outbreak every year since the beginning of the epidemic in the US (season 2013/14).

The full report is available.

Science Page: Detecting influenza virus with a portable device

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.

We are presenting today the work done in Dr. Cheeran’s lab on the detection of influenza virus in farms. The objective of their research project is to develop a portable diagnostic platform that is capable of performing on-site testing of influenza viruses in swine with minimum sample handling and laboratory skill requirements.

The device is using giant magnetoresistance (GMR) technology. In a nutshell, if influenza viruses are present in the sample, they will bind to sensors, cause a disruption in resistance, and create an electric signal in the device that will be able to wirelessly transmit the result to a smartphone or computer.

Key points from this week edition:

  • Portable, hand held device for detection of influenza A virus (IAV) based on giant magnetoresistance (GMR) biosensor has been developed.
  • Although in its developmental stage, if successful this test has the potential for rapid on-site testing of influenza viruses in swine.

The first sensitivity tests of the device look very promising!

Remembering Dr. Bob Morrison

05-16-4001a
Source: National Hog Farmer

Robert Barclay Morrison, of Roseville, MN, died tragically in an automobile accident on May 2, 2017 at age 64 while traveling in the Czech Republic. He is survived by wife Jeanie Morrison, three children, Jessie (Eric) Bain, Peter (Eva) Morrison, and William Morrison, and grandson Ian Bain; sister, Mary Walker and children, Hilary, Cameron, D’Arcy, Andy and brother, Sandy (Juliette) Morrison and children, Jeremy and Jamille.

Robert (Bob) was born February 21, 1953 in Calgary, then moved to Montreal where he spent his childhood years. His family moved to Saskatchewan where he attended high school and the University of Saskatchewan (B.S., Doctorate in Veterinary Medicine). As a young veterinarian, Bob traveled by bicycle across Europe until landing in a small German town where he immersed himself as the local veterinarian. His love of travel, driven by a desire to learn and understand the world and people around him, continued throughout his life and aided him in becoming a global expert in Veterinary Population Medicine with a focus on swine health.

Bob moved to Minnesota in 1981 to teach and study at the University of Minnesota (PhD, MBA). Here he met his wife and love of his life, Jeanie, who was his nurse while he recovered from knee surgery. Shortly after marrying, Bob and Jeanie moved with daughter Jessie to Colombia where Bob worked for the United Nations. He returned to Minnesota in 1986 to begin his tenure as Faculty in the Department of Veterinary Population Medicine at the University of Minnesota. Bob cherished his time teaching and mentoring veterinary graduate and undergraduate students for the duration of his life. Bob was a brilliant data scientist and leader in his industry; he guided responsible vaccination and antibiotic use domestically and globally, responded to outbreaks and pandemics, and advocated for safe and ethical pork production.

A man of the utmost integrity, Bob was a beloved father, husband, uncle, father-in-law, brother-in-law, grandpa and friend. He was honest, hard-working, loyal, open-minded, grateful, genuine and humble. He was a kind man with a gentle soul. He cherished his children and grandchild, and cared endlessly for his wife. Bob was happy as long as his wife Jeanie was by his side; together they traveled the world, were active in their community and church, started a squash scholarship for underserved youth, opened their home to students, and passionately supported their children. Bob had many hobbies including bee-keeping and making “Bob’s Other Honey,” leatherworking, watching hockey, woodworking, sailing trips with friends, whist, biking and playing squash.

Memorial contributions may be made to one of two organizations close to Bob’s heart:

  • The University of Minnesota Foundation SquashScholars Scholarship (established by Bob and Jeanie) by mail to U of M Foundation, PO Box 860266, Minneapolis, MN, 55486-0266, or online at https://give.umn.edu/giveto/squashscholars (Tax ID: 41-6042488)
  • Global Health Ministries (Project #79 AL -P0001) for Dr. Mark Jacobson’s HealthMinistries in Arusha, Tanzania by mail to 7831 Hickory St NE, Fridley, MN 55432 (Tax ID: 36-3532234).

Visitation will be at Falcon Heights United Church of Christ (1795 Holton St, Falcon Heights, MN 55113) on Thursday, July 6, 5:30-7:30 PM.

Funeral Services will be at Roseville Lutheran Church (1215 Roselawn Ave W, Roseville, MN 55113) on Friday, July 7, 7 PM.

Science Page: High levels of dietary zinc under a cloud

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.

The addition of zinc in pig’s diet had been a common way to fight against enteric issues at weaning without using antimicrobial in some European countries whereas its use was prohibited in others. Earlier this month, the European Union decided to homogenize practices over the continent by banning the use of high levels of zinc in the diet over environmental and antimicrobial resistance concerns. This new legislation will be implemented progressively over 5 years.

Key points from this week edition:

  • High level (2,500 – 3,000ppm) zinc use (HZU) in feed for 1 to 2 weeks post weaning to counter enteric disease is perhaps the most widely adopted alternative to antibiotic use in pig production globally.
  • The European Union just announced a ban on HZU in piglet feed, to be phased in over 5 years
  • Banning of an effective and widely adopted alternative to antibiotics, at least in part due to perceived concerns about coselection of resistant bacteria, adds another layer of complexity to the development and validation of all interventions to replace antibiotics in food animal production.

Read Dr. Peter Davies’ explanation of the reasons behind this ban.

Science Page: Incidence risk and incidence rate

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’s Science page is a follow-up from the one presented last week and focuses on the difference between incidence rate and incidence risk. Those two epidemiological measurements are often mistaken for one another.

Key points from this week edition:

  • Incidence risk is a measure of disease occurrence over a defined period of time. It is a proportion, therefore takes values from 0 to 1 (0% to 100%).
  • Incidence rate takes into account the time an individual is at risk of disease. It is not a proportion since it defines the number of cases per animal or farm time at risk.
  • Incidence risk and Incidence rate are often confused. Incidence risk and rate are numerically the same when the period at risk does not vary across individuals being studied.

Take a look at the complete report to see an example of the difference between incidence risk and incidence rate on farms.

 

Science page: How farm structure and demography impact disease detection

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’s edition reports the latest research on modeling the spread of swine vesicular diseases based on farm structure and number of sites. The model was then used to establish an expected time to detection. Two virus strains (high versus low virulence) were evaluated with the model to assess how the strain would influence the time to detection in a farm.

Key points from this week edition:

  • The models showed that the virus persisted longer in farms with a farrowing unit.
  • It is more difficult to diagnose FMD when the strains cause low mortality or no mortality.

Click on the link to see the details about disease spread models.