**HERALD (Health Enhancement through Rapid Assessment of Livestock Diseases)** is a collaborative project delivering fast, practical diagnostics for Johne's disease (JD) in cattle, with limited feasibility work preparing the platform for future bovine tuberculosis applications. JD is widespread and costly for dairy and beef producers, undermining animal welfare and farm profitability. Current widely used diagnostics identify **only around 20% of infected animals**, delaying critical management decisions. JD-affected herds show higher somatic cell counts and increased mastitis risk. Farmers and vets need tools that identify infection long before visible signs or productivity losses appear. HERALD's solution is a dual-format diagnostic platform **built on novel mycolic-acid antigens** to detect disease antibodies in serum: * **A high-throughput screen ('ELISA')** for veterinary laboratories to screen large groups efficiently * **Rapid lateral flow test (LFT)** providing same-day, cow-side results for immediate management decisions To accelerate adoption and support evidence-based planning, the project will create a **free, open-access JD database** with anonymised prevalence information and benchmarks for farmers, vets and programme managers. Proof-of-concept studies indicate these proprietary antigens deliver higher sensitivity and enable earlier detection than existing commercial tests, identifying infection years before symptoms, transmission or productivity losses occur. **One Health Benefits:** JD is caused by _Mycobacterium avium_ subsp. paratuberculosis (MAP), which has also been detected in **20-50% of Crohn's disease patients** compared to lower rates in healthy individuals, with both diseases sharing remarkable clinical similarities. MAP appears in **2% of pasteurized milk and 9% of infant formula**, as it resists pasteurization, potentially exposing humans through the food chain. There are considerable efforts to move to 'Johne's free herds'. HERALD's database will provide high-quality field data informing future research and public-health dialogue. **Welsh Innovation Leadership** HERALD represents collaboration between Welsh companies and a specialist English lateral flow manufacturer, combining expertise in biochemistry, AI, and veterinary science. Most work will be conducted in North Wales, supporting local innovation and economic impact through Welsh farmers/vets and the MSParc Agritech Cluster. **Expected Outcomes** HERALD will deliver a laboratory-based ELISA for early detection of JD infection, validated on \>1300 serum-samples (600 this project), a prototype on-farm LFT, initially for specialist applications, an operational open database, and technical groundwork for commercial launch. Benefits include reduced JD spread, lower mastitis burden, improved milk quality and animal welfare, and support for responsible antimicrobial use. This breakthrough platform positions Wales as a global leader in livestock diagnostic innovation while addressing farmer needs and supporting One Health.

Although bovine TB in cattle has a very high profile, it is much less widespread than another disease caused by a mycobacterium, Johne's disease. Johne's, caused by _Mycobacterium avium_ paratuberculosis, is an infectious wasting disease which develops very slowly but statistically is present in around 70 % of herds (albeit perhaps in very few animals). The disease causes reductions in milk and beef yield; moreover, the organism is very difficult to kill by pasteurisation, and in principle can enter the food chain. There is some evidence that there are elevated levels of the Mycobacterium in Crohn's patients, and an on-going 'discussion' as to whether there is a causal link. Johne's disease is notifiable in many countries, but currently not in the UK; should it become notifiable, there would be a very major problem for UK agriculture. Not surprisingly, supermarkets are increasingly sourcing exclusively from 'Johne's free' herds. Many farmers are embracing this challenge and carrying out extensive testing of their animals. However, current assays available are very limiting. Fecal PCR or culture are widely used but only reliable in late stage disease - when there may be visible symptoms anyway. Commercial serological assays (using antigens to detect antibodies in serum) are also commonly used. However, although they give very few false positives, they reputedly pick up only around 20 % of the 'positive' animals. **Eradicating the disease requires earlier diagnosis.** Diagnostig have developed a serodiagnostic based on a set of unique proprietary synthetic molecules identical to cell wall components of the mycobacterium and have developed an assay which appears to detect infection earlier than the standard approaches, and which does so without interference by vaccination for Johne's disease or for bovine TB. This project will involve a real-time study using animals from local herds to compare the Diagnostig device with commercial serodiagnostics, and with PCR. Working closely with local farmers, and supported by NFU Cymru, samples will be provided, to correspond where possible with their routine sampling times, and evaluated in the Diagnostig assay using an established set of antigens. A robust analysis of results compared to those of standard assays will provide firm evidence that the new method, which uses a completely different approach to others, will provide farmers, and associations validating 'Johne's free' status, with a much better way of detecting, and therefore managing, early infections with Johne's disease.

"Although infection with _Mycobacterium tuberculosis_, the cause of TB, is very widely studied, non-tuberculous mycobacteria (NTMs) are much more common in the environment but generally do not present any human health problems. However, they are a significant problem in patients whose immune systems are compromised. Thus, up to 10-20 % of cystic fibrosis patients are infected with _Mycobacterium abscessus_. Infection prevents transplantation, and is spread from patient to patient, requiring isolation; treatment can take two years - with a 60 % chance of failure. The problem is so severe that all patients currently are screened; this uses an expensive method, compromised because patients can be positive in the assay but not show clinical disease. **A rapid, cost effective method of diagnosis, which could also monitor the progression of infection and treatment, would represent a step change for clinicians.** **Diagnostig Ltd.** has prepared, in the laboratory, a suite of molecules identical to individual components of complex mixtures present in mycobacteria, the detailed compositions of which are characteristic of a particular species. These molecules bind to antibodies present in the blood of patients with TB, and this antigen-antibody binding can very effectively identify active tuberculosis disease even in patients who have been vaccinated or have 'latent' disease. With appropriate antigens, it can also detect bovine TB and distinguish infection by _Mycobacterium avium_ paratuberculosis in cattle, the cause of Johne's disease. This project will establish that, by appropriate choice of antigens, it can provide a rapid, cheap diagnosis of infection by NTMs, demonstrated using _M.abscessus,_ and also _M. avium_, infection in cystic fibrosis. The company will use its proprietary antigens to evaluate sera from patients with no infection, those positive by standard blood assays but with no clinical signs, and those also showing clinical signs. Samples will be provided, with appropriate ethical approvals, by **Royal Papworth Hospital** **Trust** and expert clinical input on assay development will be provided by Prof. Floto."

Tuberculosis remains one of the most significant causes of death, particularly in individuals co-infected with HIV-AIDS; co-infection can lead to a life expectancy of a few weeks and has, for example, reduced life expectancy in South Africa by around 10 years. Although there are many methods that are supposed to detect the disease, in practice none of these can give a diagnosis within a single visit and many do not distinguish latent from active TB - a major problem given that the World Health Organisation estimates that a third of the world population has latent disease. The normal protocol for diagnosis uses a combination of several biochemical assays as well as physical observation. The WHO has identified a clear need for a reliable point of care assay that will provide a result within minutes and which can be distributed in high-burden TB populations for less than $ 10. This project seeks to validate just such a device, based on the recognition by antibodies in the serum of patients with active TB of novel synthetic lipid antigens identical to components of TB cells. The assay (patents applied for) has been shown to provide good levels of sensitivity (correct detection of TB positive serum compared to clinical diagnosis) and specificity (correct detection of TB negative serum) in a blind trial on 250 samples from high burden TB populations, and to do so within 30 minutes without the need for laboratory equipment. This project will seek to improve further the performance of the device and provide proof of concept that it works to the required standard with serum from a range of different types of co-infected patients, including those co-infected with HIV/AIDS and those with non-pulmonanry TB. It will put in place all the necessary data and quality control systems to provide a design lock for the device and to take it to the next stage of external validation and then to commercial production.

We have developed a novel device for the detection of TB which works in under 30 minutes; this is based on the recognition of unique molecules identical to components of the cell walls of mycobacteria by antibodies present in the serum of individuals with active TB. The target set by the World Health Organisation is for a field device that works rapidly and reliably and can be sold in high burden TB countries for around $ 5 - 10; our current device works in 15 minutes, does not require electricity or a specialist laboratory, and is expected to meet the cost criteria. We already have some patent protection applied for and need to confirm that we can obtain proper protection for a number of new disclosures. We need to validate our method in comparison with other devices currently available for use in a laboratory and which generally take several hours to provide a result, and to compare our method with the 'gold standard' of cell culture, that can take several weeks to provide a result. With this information to hand, we need to develop a detailed plan for the route to market, including the development of strict product specifications, quality control systems, and a strategy for achieving recognition by Government Agencies and bodies such as the WHO. If we can optimise the device, gain such recognition and meet the challenges of market penetration, a conservative estimate of the market need for such a device in high burden TB countries alone is some 50 million units per annum.