Viral hemorrhagic fevers : Treatment, symptoms, advice and help
About viral hemorrhagic fevers
The viral hemorrhagic fevers are a group of disease caused by several different viruses which cause hemorrhagic manifestations.
Viral hemorrhagic fevers: Incidence, age and sex
Viral hemorrhagic fevers can afflict any age group though some are milder in children while others in adults. They are endemic world-wide, each virus having its own area of prevalence.Lassa fever is widespread in West Africa, where it accounts for 15% of adult hospital admissions. Ebola and Marburg viruses cause small epidemics but have high fatality rates. Kyasanur forest disease is a tick-borne viral hemorrhagic fever currently confined to a small focus in Karnataka, India.
Signs & symptoms of viral hemorrhagic fevers : Diagnosis
All viral haemorrhagic fevers have similar non-specific presentations with fever, malaise, body pains, sore throat and headache. On examination conjunctivitis, throat injection, an erythematous or petechial rash, haemorrhage, lymphadenopathy and bradycardia may be noted.
Causes and prevention of viral hemorrhagic fevers
Six of the viral haemorrhagic fevers are caused by arthropod borne viruses - Crimean-Congo Kyasanur forest disease and Omsk by ticks & Dengue, Rift Valley Fever and yellow fever by mosquitoes. Others like lassa fever are caused by infected animals or their material. Prevention of these infections involves use of repellant creams and barrier clothing/nets. Vaccines are available for some of these infections. Ribavirin has been used as prophylaxis in close contacts in Lassa fever but there are no formal trials of its efficacy.
Viral hemorrhagic fevers: Complications
Haemorrhage is a late feature of an established severe disease and may lead to shock. Hepatic and renal failure may occur. Bradycardia and ECG abnormalities are common. Encephalopathy may develop. Deafness affects 30% of the survivors.
Viral hemorrhagic fevers: Treatment
The clue to the diagnosis will come from the travel and exposure history. The causative virus may be isolated, or antigen detected, in maximum security laboratories from serum, pharynx, pleural exudates and urine. It is important to exclude other cause of fever, especially malaria, typhoid and respiratory tract infections.
General supportive measures are required for dehydration, electrolyte imbalances, renal & hepatic failure. Transfusion of blood or blood products may be required. Ribavirin is given intravenously (100mg/kg, then 25mg/kg daily for 3 days and 12.5mg/kg daily for 4 days) for some fevers like Lassa fever. Once hemorrhagic fever is confirmed, isolation is mandatory and good infection control practices will prevent further transmission.