As African swine fever continues to threaten pig production, livelihoods and safe trade worldwide, the World Organisation for Animal Health has published new guidelines to help countries evaluate ASF vaccines in the field and monitor their use after vaccination.
African swine fever remains one of the most serious transboundary animal diseases affecting pig production globally. With vaccine development advancing rapidly and some products already receiving regulatory approval in certain countries, the World Organisation for Animal Health (WOAH) has released new guidance to support safer, evidence-based decision-making.
The new document, titled “Guidelines for African swine fever vaccines: field evaluation and post-vaccination monitoring”, provides practical guidance for Veterinary Services, competent authorities and stakeholders involved in the possible deployment of ASF vaccines.
Promising vaccines, but strict safeguards are needed
Vaccination against African swine fever is an evolving field. Several vaccine candidates are under development, and some live attenuated vaccines have already been approved in specific national contexts.
However, WOAH stresses that only high-quality vaccines manufactured in accordance with international standards should be used. Vaccination decisions must not be driven only by emergency pressure or field demand. They must be based on reliable evidence, local epidemiological conditions and a clear assessment of expected benefits and potential risks.
The guidelines therefore provide a practical framework to help countries design, implement and evaluate field studies before launching national or regional vaccination programmes.
Field evaluation at the centre of decision-making
A vaccine may appear promising under laboratory conditions, but its performance in the field depends on many factors. These include production systems, biosecurity levels, virus circulation, animal movements, data quality, laboratory capacity and the ability of field teams to apply protocols correctly.
For this reason, WOAH places strong emphasis on well-designed field trials. The guidelines cover key technical elements such as case definitions, study design, randomisation, data collection and validated laboratory testing.
They also include practical tools, such as sample size calculators and recording form templates, to help countries and field teams apply the guidance directly.
Post-vaccination monitoring is essential
Vaccination does not end when animals receive a dose. Countries must continue to monitor vaccine performance under real-world conditions, detect possible adverse events and adjust their strategies when needed.
The guidelines recommend systematic post-vaccination monitoring, including vaccine effectiveness assessment, pharmacovigilance and periodic programme review.
Where feasible, WOAH also recommends genomic surveillance, including whole genome sequencing, to detect potential reversion to virulence, recombination events or viral evolution over time. This is particularly important when live attenuated vaccines are used.
Vaccination is not a standalone solution
WOAH makes it clear that vaccination alone cannot control African swine fever. It must be integrated into a broader prevention and control strategy that includes biosecurity, surveillance, movement control, early detection, rapid reporting and coordination between neighbouring countries.
This message is particularly important for countries with diverse pig production systems, including smallholder farms, backyard production and commercial units. In such contexts, poorly planned vaccination or the use of substandard products could create additional risks instead of solving the problem.
A key tool for Veterinary Services
For Veterinary Services, these guidelines provide an important reference for assessing ASF vaccines, avoiding poor-quality products and building vaccination programmes that are scientifically justified, transparent and adapted to the local context.
WOAH also encourages countries to share data generated through field trials. Since African swine fever is a transboundary disease, evidence produced in one country can help others facing similar production systems and epidemiological risks.
Countries with limited resources may also draw on evidence from comparable settings, with support from WOAH Reference Laboratories and Collaborating Centres.
Making the right decision at the right time
By publishing these guidelines, WOAH reminds countries that ASF vaccination must be approached with caution, technical rigour and responsibility.
The key question is not only whether a vaccine exists. It is also when to use it, under what conditions, with which monitoring system, and with what guarantees of quality and safety.
As African swine fever continues to affect pig production, rural economies, food security and safe trade, these new guidelines provide countries with a practical framework for making better-informed and safer decisions.
