Which of the following is NOT a focus area of the OIE?

The focus areas of the OIE (World Organisation for Animal Health) are centered primarily on animal health and welfare, the prevention and control of animal diseases, and ensuring transparency in animal disease information. While human health can be influenced by animal health issues, the OIE itself does not specifically focus on human health improvement; this is typically the realm of public health organizations like the WHO.

The other areas listed are core to the OIE's mission. Transparency in animal disease information is vital for managing and controlling diseases that can affect both animals and humans. Food safety and animal welfare are also critical components, as they ensure that animals are treated humanely while providing safe food products, thus contributing to overall public health indirectly. The promotion of veterinary services aligns with their goals of enhancing animal health worldwide, ensuring that veterinary practices are effective and widely available. Therefore, human health improvement stands apart as not a direct focus of the OIE.