Haemorrhagic Fever Viruses

Haemorrhagic fever viruses are found within several families. They have natural transmission cycles among animals and are therefore geographically restricted to certain areas. Flaviviruses are enveloped positive-sense single-stranded RNA viruses, about 50 nm in diameter. Yellow fever and dengue haemorrhagic fever occur in the tropics and adjacent subtropics and are transmitted by mosquitoes (Aedes and Haemagogus). The host reservoirs of yellow fever virus are humans (urban form) and monkeys...

Clinical Syndromes

Common aetiological agents (including common non-viral causes) Arteritis, see Polyarteritis Arthritis arthralgia arthropathy Chronic fatigue syndrome, see Postviral chronic fatigue syndrome Congenital disease (see also Perinatal generalized infection) Conjunctivitis (see also Keratoconjunctivitis) Seen in various virus infections (rubella, rubella vaccination, parvovirus B19, mumps, alphaviruses) and in chlamydial (Reiter's syndrome) and bacterial infections (Haemophilus influenzae,...

Symptoms And Signs

Man is infected following bite of the tick I. ricinus (and I. persulcatus for Eastern TBE). In highly infested areas such exposure will not always be recalled by the patient. The prodromal phase of TBE lasts 2-12 days and has no pathognomic symptoms. At this stage the disease will most commonly be diagnosed as a non-specific fever with headache and myalgia. If an EEG is performed, pathological findings may, however, be detected. The 'major disease' (secondary phase) may follow after a...

Therapy And Prophylaxis

Supportive therapy only is indicated for most well nourished children. Antibiotic treatment is indicated for bacterial otitis media and pneumonia. Vitamin A (100,000 units for less than 12 months of age, 200,000 units for over 12 months of age) has resulted in 50 reduction of mortality in developing countries. In severe cases (including immunocompromised children), ribavirin has been administered systemically based on in vitro susceptibility testing, and some children have shown evidence of...

Laboratory Diagnosis

Virus isolation, which is the preferred method for diagnosing productive CMV infections, is performed on urine and or throat or genital secretions, milk and blood. The sample should be mixed with a suitable transport medium, brought to the laboratory as soon as possible and never be frozen. CMV is grown in human lung fibroblasts, and the use of monoclonal antibodies allows an early detection of virus-infected cells (24-48 hours). Monoclonal antibodies may be used for the detection of CMV in...

Classification And Nomenclature Of Human And Animal Viruses

The present universal system for virus taxonomy includes family, genus and species. Virus families and subfamilies are designated by terms ending in -viridae and -virinae, respectively. Families represent clusters of genera of viruses with apparently common evolutionary origin. Genera are designated by terms ending in -virus. The criteria used for creating genera differ between families. Virus characteristics used for classification vary from simple to complex structure, including nucleic acid...