Lassa fever, treatment

Treatments with immune globulin vaccines are useful against Crimean Congo hemorrhagic fever, Rift Valley fever, Bolivian hemorrhagic fever, and Lassa fever Yellow fever vaccine is the only established and licensed vaccine for a hemorrhagic fever several others are under development... 

Adverse effects Side effects reported for oral or parenteral use of ribavirin have included dose-dependent transient anemia in Lassa fever victims. Elevated bilirubin has been reported. The aerosol may be safer, although respiratory function in infants can deteriorate quickly after initiation of aerosol treatment and therefore, monitoring is essential. Because of teratogenic effects in experimental animals, ribavirin is contraindicated in pregnancy. 

Unlabeled u.ses of ribavirin include aerosol treatment of influenza types A and B and oral treatment of hepatitis, genital herpes, and Lassa fever. Ribavirin does not protect cells again.st the cytotoxic effects of the AIDS virus. 

Ribavirin is a synthetic guanosine analogue, with in vitro activity against a broad spectrum of DNA and RNA viruses, and retroviruses, including HIV. Ribavirin has been used for treatment of a variety of viral infections, including respiratory syncytial virus bronchiolitis and pneumonia, measles, influenza types A and B, Lassa fever, hemorrhagic fever with renal syndrome (Hantaviruses), hepatitis C, and HIV infection. It is used commonly now along with interferon alpha for treatment of hepatitis C infection. There is no known direct nephrotoxicity of ribavirin. 

In the United States ribavirin has been approved (1987) only for the treatment of respiratory syncytial virus (RSV) in children, while the drug is marketed in over 20 countries for many other viral diseases. Clinical potentials of ribavirin are being evaluated against influenza, measles, AIDS, dengue, and lassa fever. 

Ribavirin is indicated in the treatment of carefully selected hospitalized infants and young children with severe lower respiratory tract infections due to respiratory syncytial virus (RSV). In addition, ribavirin (600 to 1800 mg/day for 10 to 14 days) has shown effectiveness in acute and chronic hepatitis, herpes genitalis, measles, and Lassa fever. 

Intravenous and/or aerosol ribavirin has been used occasionally in treating severe influenza virus infection and in the treatment of immunosuppressedpatients with adenovirus, vaccinia, parainfluenza, or measles virus infections. Aerosolized ribavirin reduces duration of fever but has no other beneficial effects in influenza infections in hospitalized children. Intravenous ribavirin decreases mortality in Lassa fever and has been used in treating other arenavirus-related hemorrhagic fevers. Intravenous ribavirin is beneficial in hemorrhagic fever with renal syndrome owing to hantavirus infection but ineffective in hantavirus-associated cardiopulmonary syndrome or SARS. 

Clinical use and toxicity Ribavirin is used in aerosol form for respiratory syncytial virus infections. Early intravenous administration decreases mortality in Lassa fever and other viral hemorrhagic fevers. Ribavirin has recently been shown to have efficacy in treatment of hepatitis C viral infections. Aerosol ribavirin may cause conjunctival or bronchial irritation. Systemic use results in dose-dependent myelosuppression. Ribavirin is a known human teratogen. absolutely contraindicated in pregnancy. 

Ribavirin is a nonimmunosuppressive nucleoside analogue with broad antiviral properties,31 and is of proven value for some of the VHF agents. Ribavirin reduces mortality from Lassa fever in high-risk patients,32 and presumably decreases morbidity in all patients with Lassa fever, for whom current recommendations are to treat initially with ribavirin 30 mg/kg, administered intravenously, followed by 15 mg/kg every 6 hours for 4 days, and then 7.5 mg/kg every 8 hours for an additional 6 days.30 Treatment is most effective if begun within 7 days of onset lower intravenous doses or oral administration of 2 g followed by 1 g/d for 10 days also may be useful. 

Jahrling PB, Frame JD, Rhoderick JB, Monson MH. Endemic Lassa fever in Liberia, IV Selection of optimally effective plasma for treatment by passive immunization. Trans R Soc Trop Med Hyg. 1985 79 380-384. 

Patients receive supportive therapy, but generally speaking, there is no other treatment or established cure for VHF.s. Ribavirin, an ami-viral drug, has been effective in treating some individuals with Lassa fever or HFRS. Treatment with convalescent-phase plasma has been used with success in some patients witli Argentine hemorrhagic fever. 

Ribavirin, an antiviral drug, has been used with succc.ss in Lassa fever patients. It has been shown to be most effective when given early in the course of the illness. Patients should also receive supportive care consisting of maintenance of appropriate fluid and electrolyte balance, oxygenation and blood pressure, as well as treatment of any other complicating infections. 

Further educating people in high-risk areas about ways to decrease rodent populations in their homes will aid in the control and prevention of Lassa fever. Other challenges include developing more rapid diagnostic tests and increasing the availability of the only known drug treatment, ribavirin. Research is presently under way to develop a vaccine for Lassa fever. 

The rest of this chapter will show how the most successful treatment modalities have developed. These include vaccination (for smallpox, polio, measles, etc.), and chemotherapy using anti-viral drugs. A large number of viral diseases still lack an effective means of treatment, and the chapter will also cover the attempts to treat the common cold and influenza the struggles with HIV and the emergence of viruses (Marburg, Ebola, Lassa) that cause haemorrhagic fever. 

C. botulinum, dengue, Ebola, EEE, Lassa, plague, Q-fever, ricin, SEB, smallpox, T-2 mycotoxin, tularemia, VEE, and WEE. Other entries involve broader treatments of more than one bacteria, virus, or toxin. Treatments for viruses, C. botulinum, and T-2 mycotoxin account for 35% of the treatment entries in the inventory (13%, 12%, and... 

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