100%

Neonatal Piglet
Mortality Rate

21.2%

Sows with
protective antibodies

14.0%

US Sow Farm Positivity
(Highest Since 2022)

⚠  The "Hidden Infection" Problem

Official Statistics Undercount the Real Burden

Veterinary experts have repeatedly stressed that the actual field impact of PED is far more severe than official case counts suggest. Because PEDV is a notifiable disease, confirmed diagnosis triggers movement restrictions — discouraging voluntary farm reporting and creating a large pool of "hidden infections."

To combat this, the industry is shifting from an eradication to a management paradigm. Experts advocate for voluntary, industry-led surveillance networks where farms and veterinarians share diagnostic data proactively. Active immunity monitoring, rather than reactive reporting, is now the critical foundation of PED control.

SHIC Alert · United States · 2026

PEDV Surges to Highest US Levels Since 2022

According to the Swine Health Information Center (SHIC) SDRS reports, PEDV case positivity has climbed significantly above expected seasonal ranges. Adult and sow farm positivity reached 14.0% — the highest recorded level since the major outbreaks of 2022. This alarming data underscores that current biosecurity and vaccination protocols alone are struggling to contain the virus, making proactive mucosal immunity monitoring more critical than ever before.

Fig. 1 · Median Diagnostics — IgG (Systemic Passive) & sIgA (Local Lactogenic) Antibody Transfer Pathways

IM Vaccination Route

IgG — Systemic Immunity

IM vaccine → Regional LN → IgG plasmablast → Blood → FcRn receptor → Colostrum → Piglet gut absorption → Systemic passive immunity

Oral Vaccination Route

sIgA — Mucosal Immunity

Oral vaccine → GALT (Peyer's patch) → IgA plasmablast → Gut-Mammary Axis homing → pIgR → sIgA in milk → Piglet intestinal mucosa → Local lactogenic immunity

Clinical Insight

A sow with high serum IgG may still have inadequate sIgA in her milk — leaving nursing piglets vulnerable to intestinal PEDV despite appearing "vaccinated." These two antibody classes must be monitored independently. sIgA persists throughout lactation (21 days), while IgG drops below protective threshold from Day 5 post-farrowing — making IgA the dominant and sustained shield for nursing piglets.

This field study evaluated five PEDV vaccination programs in a 400-sow farm (Iksan, Korea) with confirmed PEDV genotype 2b infection, measuring colostrum IgA, IgG, and virus neutralization (VN) antibody profiles using Median Diagnostics' VDPro® PEDV IgA ELISA and VDPro® PEDV IgG ELISA kits, alongside the VDx® PEDV qRT-PCR and VDRG® PEDV Ag Rapid Kit for initial diagnosis.

* p<0.01   ** p<0.0001 vs. control. ns = not significant. ★ = optimal program

Key Findings

Study Conclusion — Kang et al., 2026

"Oral administration of the live attenuated vaccine approximately 1 week before farrowing elicited the strongest IgA-mediated mucosal response. IgG levels showed no marked differences among the vaccination timings, and IgA persisted during the lactation period, highlighting the importance of colostrum IgA in protective immunity. The timing and administration route of PEDV vaccination are critical for establishing maternal immunity in piglets."

① Detect Active Infection — Immediately

Every hour without a confirmed diagnosis is time the virus spreads to neighboring pens. Pen-side antigen rapid testing eliminates the diagnostic delay — enabling same-day isolation, movement control, and farm-level response before spread becomes catastrophic.

② Monitor Sow Immunity — Before Farrowing

The Kang et al. (2026) study demonstrates that colostrum IgA is the decisive protective factor — but it is invisible without testing. Routine pre-farrowing IgA and IgG ELISA screening reveals immunity gaps in time to adjust vaccination timing, preventing the next cycle of neonatal diarrhea and productivity loss.

③ Confirm and Trace — with Molecular Precision

qRT-PCR provides the quantitative viral load data needed for outbreak severity assessment, genotyping, and epidemiological surveillance — the backbone of any voluntary monitoring network modeled on the MSHMP.

Rapid Detection  ·  On-Farm Point-of-Care

VDRG® PEDV Ag Rapid kit

Rapid chromatographic immunoassay for on-site PEDV antigen detection. Delivers reliable results in just 10 minutes without laboratory equipment. Validated in the Kang et al. (2026) field study.

Cat. No. PS-PED-11  |  10 Tests/Box  |  APQA Approved

ELISA  ·  Mucosal Immunity

VDPro® PEDV IgA ELISA Kit

Indirect ELISA to quantify PEDV-specific IgA. Accurately measures mucosal lactogenic immunity, proven by Kang et al. (2026) to be the most critical predictor of piglet protection.

Cat. No. ES-PED-01  |  192 or 480 Tests/Kit  |  Export only

ELISA  ·  Systemic Immunity

VDPro® PEDV IgG ELISA Kit

Indirect ELISA to monitor PEDV-specific IgG in sow serum and colostrum. Essential for assessing systemic humoral immune responses and evaluating overall herd vaccination compliance.

Cat. No. ES-PED-02  |  192 or 480 Tests/Kit  |  Export only

Real-Time RT-PCR  ·  Genogrouping

VDx® PEDV qRT-PCR

Multiplex real-time RT-PCR for the simultaneous detection and differentiation of PEDV Genogroup 1 and Genogroup 2 strains. Delivers definitive confirmatory diagnosis and reliable strain tracking.

Cat. No. NS-PED-31  |  96 Tests/Box  |  APQA Approved

Real-Time RT-PCR  ·  N Gene Target

Advanced TaqMan-based real-time RT-PCR targeting the PEDV N gene. Features dual Internal Positive Controls (Endo & Exo) for unmatched diagnostic reliability. Used for definitive diagnosis in Kang et al. (2026).

Cat. No. NS-PED-32  |  96 Tests/Kit  |  Export only