Nuclear-derived techniques have been well established as an important diagnostic tool to rapidly and reliably identify many diseases spreading from animals to humans, such as Ebola Virus Disease, Highly Pathogenic Avian Influenza, Middle East Respiratory Syndrome and others. While the focus these days is on COVID-19, authorities need to remain vigilant about other zoonotic diseases as well.
Over 15,000 people have been killed by Ebola since its discovery in the Democratic Republic of Congo (DRC) in 1976, according to the World Health Organization (WHO). Since then, the virus has mainly taken its toll in 13 countries in Africa. Ever since the 2014-2016 major outbreak in West Africa, the IAEA, in partnership with the Food and Agriculture Organization of the United Nations (FAO) and in collaboration with the WHO, has supported Ebola diagnosis in African countries. With more veterinary officials now able to diagnose the disease rapidly and reliably, these countries are better prepared for early detection to prevent major outbreaks and have advanced in tracing the molecular epidemiology of Ebola and other viral haemorrhagic fevers (VHFs) with the help of molecular genetic tools.
Ebola is a deadly zoonotic disease that is thought to have originated in fruit bats, which then contaminated other animals before the virus reached humans. The more the human population expands into previously uninhabited areas, the higher the risk of people getting into contact with carriers of previously unknown zoonotic diseases. “It is therefore crucial for all countries to be prepared to detect emerging zoonotic diseases as early as possible, preferably before they enter into human populations, and to take appropriate response actions,” said Michel Warnau, in charge of the IAEA’s technical support activities in this area.
During the 2014-2016 Ebola outbreak, close to 30,000 people got infected in Sierra Leone, Liberia and Guinea. Three months had passed before the diagnosis could be made in Guinea, where the outbreak began. Over 2,500 people lost their lives because of the lack of diagnostic capacity and resources. At the end of 2014, the governments of Guinea and several other African countries requested the IAEA to support them in improving their capacities in Ebola diagnosis.
Through nuclear-derived techniques such as the enzyme linked immunosorbent assay (ELISA) and the real-time reverse transcription-polymerase chain reaction (RT-PCR) (see Nuclear-related techniques in disease diagnosis), scientists are able to diagnose Ebola much faster than with conventional methods.
The IAEA, through its technical cooperation programme, provided assistance to experts from Africa on the use of these techniques. “We trained 142 local staff to carry out early diagnosis of zoonotic diseases under adequate bio-safety conditions and provided them with the equipment and the diagnostic kits needed to perform the assays,” said Ivancho Naletoski, Animal Health Officer at the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture.
“As zoonotic diseases are at the frontier between animals and humans, it was necessary to train staff from various backgrounds, such as veterinarians, public health technicians and wildlife experts,” said Naletoski. Samples taken from possibly infected people or animals represent a high biohazard risk. Therefore, proper handling of Ebola samples was a major focus of several of the 17 trainings delivered in 8 countries under the IAEA technical cooperation programme.
In Africa, the threat of widespread contamination remains real. The most recent outbreaks of Ebola in the DRC killed more than 2,500 people since 2018. Although the outbreaks have so far been limited to a single country, this could easily change – as wildlife that crosses borders can carry diseases between countries.