Antiviral therapy, intravenous

The treatment for smallpox is primarily supportive. Research is ongoing into antiviral therapies for smallpox but currently therapy for patients infected with smallpox remains supportive, with intravenous fluids, pain medications, and antibiotics as needed for secondary bacterial infections (Henderson, 1999). Cidofovir, an antiviral agent used primarily against cytomegalovirus infection, has shown some promise against orthopox viruses such as vaccinia and cowpox in animal studies (De Clercq, 2002). Currently it is approved in its IV form for use in the treatment of adverse effects of smallpox vaccination (CDC, 2003). 

The T-20 peptide was administered to patients via intravenous injection [4]. Because the half-life of the peptide is short (/1/2 = 1.8 h), and because it was suspected that several weeks of antiviral therapy would be needed, patients were given intravenous infusions of T-20 every 12 h for 14 days at doses ranging from 3 to 100 mg per dose. Expected plasma concentrations for T-20, based on the average ti/2 and measured in AIDS patients, over the first week of treatment are shown in Figure 10.2. 

Ribavirin is an effective treatment for Arenaviridae infections if given early. Antiviral therapy is usually administered intravenously, although multiple or milder cases may be treated orally. Dose regimens are shown in Table 4.21. Blood product replacement therapy may be required in cases of severe haemorrhage. 

There is no proven treatment for smallpox, but research to evaluate new antiviral agents is ongoing. Patients with smallpox can benefit from supportive therapy (e.g., intravenous fluids, medicine to control fever or pain) and antibiotics for any secondary bacterial infections that may occur. 

Three basic approaches are used to control viral diseases vaccination, antiviral chemotherapy, and stimulation of host resistance mechanisms. Vaccination has been used successfully to prevent measles, rubella, mumps, poliomyelitis, yellow fever, smallpox, chickenpox, and hepatitis B. Unfortunately, the usefulness of vaccines appears to be limited when many stereotypes are involved (e.g., rhinoviruses, HIV). Furthermore, vaccines have little or no use once the infection has been established because they cannot prevent the spread of active infections within the host. Passive immunization with human immune globulin, equine antiserum, or antiserum from vaccinated humans can be used to assist the body s own defense mechanisms. Intramuscular preparations of immune globulin may be used to prevent infection following viral exposure and as replacement therapy in individuals with antibody deficiencies. Peak plasma concentrations of intramuscular immune globulins occur in about 2 days. In contrast, intravenously administered immune globulin provides immediate passive immunity. 

Almost all otherwise healthy babies with bronchiolitis can be followed as outpatients. Such infants are treated for fever, provided generous amounts of oral fluids, and observed closely for evidence of respiratory deterioration. In severely affected children, the mainstays of therapy for bronchiolitis are oxygen therapy and intravenous fluids. In a subset of patients, aerosolized bron-chodilators may have a role. In selected infants, particularly those with underlying pulmonary or cardiac disease or both, with severe acute infection, therapy with the antiviral agent ribavirin may be considered. 

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