Vaccine preventable viral diseases in developing countries

There are several viral infectious diseases with a high impact on developing countries which can be prevented by immunization with existing vaccines. The most important are poliomyelitis, measles, hepatitis B and yellow fever. Vaccines against poliomyelitis and measles used within the framework of the WHO/Expanded Programme on Immunization prevent about 1.4 million deaths from measles and 360,000 cases of paralytic polio per year in developing countries, but about 1.5 million measles' deaths and 200,000 cases of paralytic polio still occur. Hepatitis B infection and its sequelae are responsible for over 50 million infections and one million deaths annually. Highly effective hepatitis B vaccines are now available and the price of these vaccines for the developing world has fallen dramatically. Despite the availability of a safe and efficacious yellow fever vaccine since 1937, 5400 cases of this disease with 3200 deaths were reported in Africa and South America from 1986 to 1988. Because of the efficacy of existing vaccines and the lack of animal reservoirs or vectors, systematic vaccination programmes within the framework of the Expanded Programme on Immunization (EPI) could theoretically eliminate and even eradicate poliomyelltis, measles and hepatitis B. Many different obstacles need to be overcome before these goals are realized.This paper was presented at the IUMS Symposium on New Developments in Diagnosis and Control of Infectious Diseases held in conjunction with the Eighth International Congress of Virology, Berlin, Germany, 24–31 August 1990.     

Modern problems of drug allergy to antibiotics in the clinical aspects of skin and venereal diseases]

Allergic dermatoses induced by antibiotics amounted to 45.2 per cent of all determined drug reactions according to the data of the Kharkov Research Institute of Dermatology and Venerology. The data on the factors favouring development of the drug dermatoses are presented. Difficulties in differential diagnosis by means of clinical and laboratory methods are indicated. The modern immunological tests of etiological diagnosis of drug resistance and the results of studying non-specific reactivity in patients with medicamentous dermatoses were analyzed. The principles of therapy and prophylaxis are summarized.     

Control of tick-borne diseases

The control of tick-borne protozoan diseases (babesiosis and theileriosis) depends on judicious integration of management, vector control, chemotherapy and immunization. The relative importance of each method will depend on the animal species involved as well as epidemiological and financial considerations. Thus, the role of economists, modellers and sociologists will become increasingly important in the future in determining the best control strategies for specific situations.The possibilities of deriving synthetic vaccines by genetic engineering techniques are exciting, but it will be some time before such vaccines supplant the currently-available live vaccine.     

Animal diseases affecting human welfare in developing countries: impacts and control

Animal diseases adversely affect human populations by reducing the amount and quality of food and fiber, and draft power. Epizootics of diseases such as rinderpest have caused massive mortality among domestic and wild animals. Extensive outbreaks of Venezuelan equine encephalltis have caused massive mortality in equines, and significant morbidity among people. Foot-and-mouth disease can cause high morbidity and great direct economic loss, and loss of markets as a trade barrier. Old diseases such as yellow fever and Rift Valley fever are still with us, and diseases such as the viral haemorrhagic fevers have suddenly appeared for the first time. The transmission of some of these diseases has been facilitated inadvertently by ecological change resulting from development projects. Animal disease control must be based on dealing with disease agents, and their hosts and vectors, as part of ecosystems and farming systems. Better disease surveiliance, diagnosis and reporting is needed. The economics of disease loss and the benefits of interventions must become part of the decision-making process.This paper was presented at the IUMS Symposium on New Developments in Diagnosis and Control of Infectious Diseases held in conjunction with the Eighth International Congress of Virology, Berlin, Germany, 24–31 August 1990.     

Nutrition and infectious diseases in developing countries and problems of acquired immunodeficiency syndrome

Infectious diseases are the major causes of death and morbidity in underdeveloped countries, particularly in children. Increasing evidence suggests that malnutrition-both Protein-Energy type Malnutrition (PEM) and essential micronutrient (vitamins, trace minerals, essential amino acids, polyunsaturated fatty acids) type-is the underlying reason for increased susceptibility to infections. On the other hand, certain infectious diseases also cause malnutrition, which results in a vicious cycle. Before its viral origin was known, acquired immunodeficiency syndrome (AIDS) had been termed the thin disease because cachexia was AIDS' main clinical manifestation. The relationship between infection and malnutrition is well documented in the literature. Our experience supports this. Preventive and therapeutic measures are suggested.