Newcastle disease is caused by a virus that is deadly for chickens and some other poultry. It spreads rapidly within and between flocks, and commonly sweeps through villages throughout Asia and Africa. The disease kills many of the scavenging chickens that are important to these communities. Village chickens are often the only source of protein and micronutrients for smallholder farmers and also provide vital income. Up until the 1980s, it was impossible to control Newcastle disease in village chickens because the available vaccines needed refrigeration.

In 1984, Professor Peter Spradbrow of the University of Queensland and Professor Latif Ibrahim (1938–2022) of the Universiti Pertanian Malaysia were funded by ACIAR to research a vaccine that could provide protection from Newcastle disease in village environments. They developed a heat-tolerant vaccine (HRV4) that could be coated onto chicken feed. The research first focused on the vaccine’s use in villages in Malaysia, and then extended to other countries in South-East Asia.

The HRV4 vaccine was commercialised by an Australian company, which was later taken over by an American firm. However, affordability of the vaccine and distribution problems limited the initial uptake of the technology in the target countries. Recognising these problems, Professor Spradbrow gained support from ACIAR to develop a new avirulent vaccine, known as I-2, in 1995. From this seed vaccine the heat-tolerant vaccine can be made locally at low cost and administered to chickens in drinking water or by eye drops. This project also developed training methods for people in partner countries to produce the I-2 vaccine from seed stocks supplied free from Australia. The technology and training were also extended to Vietnam and a number of countries in eastern, southern and western Africa.

Research and vaccine development to combat Newcastle disease in eastern and southern Africa was consolidated under new ACIAR-supported projects from 1995 to 2001. Led by the University of Queensland, the projects in Africa resulted in development of comprehensive vaccine production, distribution and administration systems for the I-2 vaccine.

The ACIAR-funded research was followed by a series of projects funded by the Australian Agency for International Development (AusAID) that continued the Newcastle disease control activities in Mozambique and expanded them into Ethiopia, Tanzania, Malawi and Zambia.

An impact assessment in 2013 concluded that total net benefits to the four African partner countries was estimated at around A$479 million, with A$80.6 million of those benefits attributed to ACIAR.

Dr Robyn Alders, now Honorary Professor at the Australian National University and a Senior Consulting Fellow with the Chatham House Global Health Programme, worked on the ACIAR-funded project in Mozambique. Dr Alders was involved in taking the thermotolerant vaccine from Asia and adapting its use for Africa. The project actively involved men and women chicken farmers, and a novel cost-recovery program involving community vaccinators for Newcastle disease was developed.

This made the vaccination program sustainable, without needing international resources. The cost-sharing model with village farmers has been adopted in many countries in Africa and Asia, including Timor-Leste, helping to increase biosecurity against poultry diseases in those regions as well.

In addition to economic and social benefits of the project in Africa and South-East Asia, the development of the new vaccine strengthened Australia’s management of poultry diseases.

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‘In terms of clinical signs, you can’t tell the difference between virulent Newcastle disease and highly pathogenic avian influenza. This makes it difficult to rapidly identify outbreaks of avian influenza in regions where farmers are accustomed to seeing chickens die regularly from Newcastle disease,’ explained Dr Alders.

‘When farmers believe that the vaccine will prevent Newcastle disease, they are willing to pay a fair price for the vaccine and its administration by community vaccinators. Because of this investment, should vaccinated birds then die, those farmers are more likely to report that death. That then provides a more sensitive surveillance system for highly pathogenic avian influenza.’

Panama disease in bananas is caused by the soil-borne Fusarium fungus – the disease is also called Fusarium wilt. Spread by people, animals and machinery through the movement of infected banana plants, soil, water or planting material, Panama disease can survive in the soil for decades. The disease is one of the greatest threats to global banana production and control of the fungus is centred around slowing the spread of the disease and planting resistant varieties of bananas.

In the 1950s, Panama disease was responsible for widespread destruction of banana plantations in Central and South America, resulting in the abandonment of the susceptible Gros Michel variety from commercial plantations.

Banana producers then adopted the Cavendish cultivar, which was resistant to the type or race of Fusarium that had destroyed the Gros Michel industry. However, in the 1990s, a new strain of Fusarium wilt was discovered to be infecting the Cavendish banana – Tropical Race 4 (TR4). The new strain was first detected in Taiwan and spread rapidly through South-East Asia, wiping out the Cavendish-based banana industry in Malaysia and appearing in Indonesia in 1994.

TR4 made its way to Australia in 1997 and was first detected in the Northern Territory. Just six years later, the territory’s burgeoning banana industry was wiped out. However, due to strict quarantine measures, Australia’s major banana production hub in Queensland remained disease-free.

The disease reached the Philippines, one of the largest banana-exporting nations in the world, in 2005.

ACIAR funded research to evaluate Fusarium wilt resistant hybrids and cultivars in Tonga and Queensland in 1995. In the mid-2000s, with the ongoing threat and spread of TR4, two projects were established in Indonesia and led by Bioversity International to develop science-based disease management approaches.

Knowledge gained in Indonesia formed the basis of a research program between the Philippines government and ACIAR to develop a series of projects to help smallholder banana farmers fight TR4. Led by the Queensland Department of Agriculture and Fisheries, research started in 2012 to increase knowledge of on-farm biosecurity, minimise Fusarium wilt incursions, develop long-term management strategies to slow the spread of the disease and develop options to allow smallholder producers to return to economic production.

Dr Tony Pattison, Principal Nematologist with the Queensland Department of Agriculture and Fisheries, was involved in the ACIAR-supported projects in Indonesia and the Philippines since the late 2000s, and he led the Philippines-based research from 2015.

‘Many smallholder farmers were growing the highly susceptible Cavendish banana “Grand Nain” because it was preferred by consumers in the Philippines and provided a good livelihood for banana growers.

‘Different varieties of banana are not always accepted by the market, so the ACIAR-funded work concentrated on building the capacity of Philippine growers, local universities and provincial agricultural officers to help banana growers manage Panama disease.

‘The ACIAR-funded work generated much greater awareness of the severity of the disease and how easily it is transferred. The research also reinforced the importance of on-farm biosecurity practices.’

Generating a better understanding of soil biology and how this can be used more productively to prevent Panama disease, rather than relying on chemical interventions, underpinned a lot of the extension work associated with the project. Simple technologies that were tested and implemented by the farmers included growing vegetative disease-suppressive groundcovers under the banana canopy and planting more disease-resistant cultivars. These practices helped reduce the susceptibility of banana plants to the disease.

Experience with Fusarium wilt of banana through ACIAR-supported projects was vital in assisting the Australian banana industry to manage the disease when it was detected on a Queensland farm in 2015. Biosecurity Queensland was quick to quarantine the plantation at the centre of the outbreak and set up biosecurity restrictions to stop the spread of the fungus.

The expertise developed by the research team throughout the ACIAR-funded project, and the knowledge shared with Australian agencies and producers, ensured that the Australian banana industry was vigilant and quick to respond to incursions of the disease.

From 2015 to 2022, only 157 trees in northern Queensland have been diagnosed with Panama disease and had to be destroyed. Unfortunately, the area of land infected with Fusarium wilt in districts growing bananas for export production in Mindanao, the Philippines, continues to grow.

ACIAR support of efforts to manage Panama disease in partner countries, or to prevent its incursion, is ongoing. A 5-year project that started in 2020 in Indonesia, the Philippines and Laos is examining different farm management practices to increase the soil microbiome and make it harder for Fusarium to grow in the soil.

In 2022, a new ACIAR-supported project, led by Mr Stewart Lindsay from the Queensland Department of Agriculture and Fisheries, was implemented in Mozambique and Tanzania to investigate banana farming systems, the cultivars grown and production practices for susceptibility to Panama disease. The project also seeks to work with country partners and landholders to identify practical biosecurity measures to reduce risks and mitigate potential damage from the disease on small farms.

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