VADEMOS

Vaccine Demand Estimation Model - FMD

VADEMOS is a decision-support tool intended to be used to estimate current and future demand for Foot-and-Mouth disease (FMD) vaccine and predict future growth of the demand at national level. It will assist the processes needed to bridge the gap between FMD vaccine demand and vaccine production/supply in endemic countries.

It is a stochastic quantitative model which uses predictors of vaccine dose demand such as livestock population growth forecast, disease control policy related to projected FMD Progressive Control Pathway (PCP) stage, vaccination schedule and outbreak forecasting.  The model is split into prophylactic vaccination and emergency vaccination.

 

Prophylactic vaccination is the vaccine doses needed to cover the livestock population routinely as part of a country’s FMD control policy. The inputs for this are:

  • Livestock population forecast, divided into large ruminants, small ruminants, and pigs;

  • Sector proportion for large ruminants, divided into dairy, beef, and smallholder;

  • Vaccination schedule for youngstock and adult stock, this includes primary courses and boosters;

  • Proportion of total livestock covered with routine vaccination based on the predicted PCP stage.

 

Emergency vaccination is the number of vaccine doses required to carry out vaccination surrounding outbreaks.

The inputs for this are:

  • Livestock population forecast, divided into large ruminants, small ruminants and pigs;

  • Livestock population density, divided into large ruminants, small ruminants, and pigs;

  • Reactive vaccination area, the area surrounding the outbreak in which all animals are vaccinated;

  • Outbreak number forecast;

  • Proportion of outbreaks targeted for vaccination based on PCP stage.

 

PCP stages are used as a proxy for FMD control policy. Inputs relating to the PCP stages are the result of an expert elicitation study conducted by the EuFMD in 2020/21. In this study experts in the field of FMD control were asked to assign a range and mode to each PCP stage and livestock category relating to:

  • Proportion of animals routinely vaccinated;

  • Proportion of outbreaks targeted with emergency vaccination per PCP stage;

  • Percentage reduction of outbreaks in and between PCP stages.

 

Based on the expert elicitation, the EuFMD preselected values for a country based on their projected PCP stage for each year. The PCP projections are from the roadmap meetings held under the GF-TADs with in-country representatives.

 

Data on population and outbreak values are collated from FAOSTAT and the OIE WAHIS databases. Values relating to quantity of animal products, such as milk and meat, were used as a proxy for sector proportions and were also collated from FAOSTAT.

 

The tool is intended to be flexible to country requirements, and therefore the input values can be adjusted to allow for variation with in-country data. The model has been written in R language and is presented via the R Shiny interface.

 

Full details on the model will be soon available to download from this site. Meanwhile for more detail information please get in touch via the email address as follows: eufmd@fao.org

This tool is a simulation model that has been developed by the EuFMD under its 2019-2021 workplan as part of Pillar III, Component 3.4.