Abortion cases in the study had a high rate of PCV3 positivity.
PCV3 found in association with lesions in an abortion case suggesting causality.
The study looked at 730 cases from the UMN Veterinary Diagnostic Laboratory with a positive sample for PCV3, received between Feb 2016 and Jan 2018.
Out of 22 states, 18 states were PCV3 positive. PCV3 was detected in pigs from all ages.
The positive rate among fetus, piglets, nursery and finishing pigs ranged from 15% to 20%. The PCV3 rate in adults was 35%.
PCV3/PCV2 co-infection rate was 5.2%, and PCV3/PRRSV coͲinfection rate was 7.6%.
In our data, we had 67 abortion cases, and 40% of them were PCV3 positive. In one abortion case investigation, histological lesions were observed in lung tissue of aborted fetus and PCV3 in-situ hybridization showed presence of PCV3 in the lesion.
Seven PCV3 whole genome sequences were obtained. Current PCV3 genomes in the U.S shared over 98% nucleotide identities. U.S strains did not cluster together and were grouped with PCV3 sequences obtained in other countries.
It is a public, private and academic partnership to implement a system for near real time global surveillance of swine diseases.
The output of the system is a report of hazards identified and subsequently scored that may represent a risk for the US pork industry.
Developing systems to provide situational awareness to stakeholders in near-real time can facilitate the coordination between government agencies and the industry with the ultimate objective of preventing or mitigating the impact of diseases epidemics.
The system of near real time global surveillance of swine diseases is based on an online application. Initially focused on three main potential
threats: Classical Swine Fever (CSF), African Swine Fever (ASF), and Foot and Mouth Disease (FMD), it will expand to other exotic swine diseases in the US in the near future. A report, distributed on a monthly basis by SHIC, includes a list of identified hazards that may represent a risk for the US.
Several steps are needed to build the Swine Global Surveillance report as shown in the figure above.
Screening/Filtering phase: Multiple official data sources and soft data sources are systematically screened to build a raw repository. After that, an Include/exclude process is undertaken under a crowdsourcing model.
Scoring phase: A multi-criteria rubric was built based on: credibility, scale and speed of the outbreak, connectedness, local capacity to respond and potential financial impact on the US market. Each event is score independently by a group of experts.
Quality assurance (QA)/building: Its aim being to ensure that the design, operation, and monitoring of processes/systems will comply with the principles of data integrity including control over intentional and unintentional changes to information. The monthly report is put into a PDF document automatically from the app after the scoring process is finalized. At last, assembly of figures and proofreading is done before sending it to SHIC for monthly publication.
Complete automation of event capture into the database
Expansion of the list of diseases in the report
Shrinking the gap between Search/Filter phase and Final Publication – (1 week)
Expanding scoring experts panel
Process documentation – Quality assurance compliance
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.
Seasonal patterns can be seen in different cohorts located in different regions.
A comparison from a prevalence standpoint between the cohort of farms belonging to the 13 systems participating at the start of the MSHMP (CS) and the cohort of farms from systems that joined the program later (CL), was performed with the objective of assessing whether the patterns between cohorts compare.
As seen in Figure 1–CS, there was a clear shift towards more use of MLV over LVI for sow herd stability purposes. The proportion of farms using LVI in the CS versus the CL is 5% and 10%, respectively. When assessing the proportion of farms in each AASV PRRS category (Holtkamp et al., 2011) both groups are comparable (Table 1). Also the temporal pattern of infection can be seen in both cohorts as described by Tousignant et al (2014).
In summary, both cohorts of farms (CS versus CL) yield similar results which continue to highlight the robustness of the program and the representativeness of the systems contributing to this program.
PRRS virus can be detected in the environment of the farrowing house (surfaces and air) and on the udder skin of lactating sows. However, PRRSV detection in the environment decreases as time after an outbreak increases.
PRRSV was not detected in the environment after 4 months of an outbreak
Role of environmental PRRSV in the transmission of the disease is still unknown.
In this study, udder and surface wipes as well as particle deposition wipes were collected both at processing and at weaning, starting 2 weeks after the PRRSV outbreak.
Results showed that PRRSV was detected at processing up to 14 weeks after the outbreak in surfaces and udder skin of lactating sows. At weaning, PRRSV was detected up to 17 weeks post-outbreak using udder skin wipes. The number of positive samples decreased over time and the Ct values of the positive samples increased over time indicating a decrease in infection load overtime. Detection of airborne particle deposition positive samples followed a similar pattern to those of the crate surfaces and udder wipes. Virus could be isolated and sequenced from all sample types.
Udder skin and environment may play a role in the transmission and maintenance of PRRSV in piglets in breeding herds; however further research is needed to validate this observation.
Lactating sows and the farrowing environment can be sources of PRRS virus
Sampling the farrowing environment and the udder skin of lactating sows can be used to monitor for PRRSV although the sensitivity is lower than that of serum samples.
The farrowing environment and the lactating sow may serve as a source of infection for PRRSV.
Sampling started 2 weeks after a PRRSV outbreak was reported in a sow farm. Sampling was conducted from 10 litters every 3 weeks for a total of 24 weeks. Samples were collected at processing (~ 3 days of age) and included: surface wipes of farrowing crates, surface wipes of the udder skin of lactating sows, blood samples from all piglets within the selected litters.
PRRSV was detected in the farrowing crate environment and on the skin of the lactating sow at processing. The surface and udder skin wipes were less sensitive at detecting PRRSV than serum PCR at processing. However, in this study all pigs in the litter were bled which is not the standard practice in the field.
The results show that the environment and the lactating sow may serve as a source of
infection for PRRSV, indicating a need to further understand their roles to establish herd level stability.
In the event of a Foreign Animal Disease outbreak it is required for all swine premises to have a Premises Identification Number
Having correct location data associated with PINs is imperative for responding to an FAD at a farm or large scale level
Validating and correcting information associated with PINs is an important step in FAD preparedness
What is a PIN?
A federal swine Premises Identification Number (PIN) is a unique, seven character ID, allocated to a premises where swine are produced, kept or moved through.The PIN is a key component in identifying and tracking swine as they move through the United States.The USDA APHIS PIN allocator generates a PIN once a premise has been registered through a state’s animal health official.
What is it used for?
PINs are essential for continuity of business (COB) during a Foreign Animal Disease (FAD) event.Any premises wishing to move pigs during an FAD event must have a PIN.
Unfortunately, there are two common problems in the industry, creating poor PIN information:
incorrect address linked to a site
two geographically distinct sites sharing the same PIN
It is important to find and correct these or other issues that are identified for an existing
PIN. An easy way to identify issues is to validate the locations associated with aPIN using a mapping site such as Google Maps to check the accuracy of the address and coordinates.
To correct these errors it will be necessary to apply for a new PIN via the state’s animal health official.