Co-ordinated studies of infection

Full text: Infections are responsible for more than half of all deaths among the poorest 20% of the world and more than two-thirds of the deaths in Africa. HIV/AIDS, TB and malaria are the world's great killers. Three million people died of AIDS in 2001. Tuberculosis accounted for 1.7 million deaths in 2000. In the same year, malaria killed more than 1 million people, mostly children in Africa. Worldwide, they account for 41% of global DALYS (disability adjusted life years), a rough measure of aggregate economic loss. The strategic goal for technical cooperation with Member States is that it shall increasingly promote tangible socio-economic impact by contributing directly in a cost-effective manner to the achievement of the major sustainable development priorities of each country. With rapid developments in genetics and biotechnology, molecular biological and immunological techniques, including those based on radionuclides, are playing an unprecedented role in medicine. In the field of infections, the IAEA has successful ongoing projects in developing countries on malaria and tuberculosis, related to the use of molecular biological techniques like polymerase chain reaction and hybridisation with 32P- labelled probes, dot blot hybridisation, single-strand conformation polymorphism (SSCP), etc. for monitoring drug resistance and strain variation. Other ongoing IAEA projects on communicable diseases address hepatitis C, dengue, filariasis, diarrhoeal diseases and human papilloma virus infection. These projects provide valuable support for national programmes and clinicians. In terms of Nuclear Medicine imaging techniques the Agency has three areas of developments: 1. Assist programmes of transfer of technology related to traditional white cell labelling techniques. 2. Use of bacterial specific agents such as 'Tc99m- Ciprofloxacin ('Infecton'), and 3. Use of simple 'shake and mix' formulations such human immune globulin HIG and liposomes. One of the largest coordinated research programmes was the multi-centre trial of Infecton involving eight countries, Argentina, Chile, Egypt, Greece, India, Indonesia, Singapore and the UK. A total of 879 patients were studied. There were in total 574 positive studies and 295 negative studies with an overall sensitivity of 85.4% and specificity of 81.7% for detecting infective foci. The investigators confirmed the robustness of the preparation, ease of imaging and the absence of side effect. It also concluded that serial imaging with Infecton was useful in monitoring clinical responses and optimising the duration of antimicrobial treatment. The present strategy is to use white cell imaging and non-specific imaging with HIG and liposomes for first line approach and reserve the more specific agents for targeted clinical decisions. The use liposomes could be particularly important for assessment and delivery of pharmacologically active material at selective sites such as during fungal infection involving HIV patients. This approach may aide decisions related to toxicity and usefulness of expensive medicines such as the anti-fungal. Therefore, the Agency has a broad and strategic role in the use of radioisotope techniques for assisting many Member States with infection control programmes. (author)