RSV
...ptoms like low fever, runny nose and sore throat. After 2-5 days, the following symptoms start to appear suggesting the RSV virus: • Wheezing and high pitched, whistle breathing • Rapid breathing (more than 40 breaths per minute) • Shortness of breath • Labored breathing out ( exhalation) • Bluish tinge to the skin (cyanosis) • Croupy, seal-like barking cough • High fever A health care provider usually diagnoses the RSV infection during a physical exam. The health care provider will usually hear wheezing and other abnormal lung sounds. Chest x-rays will give some indication of whether the lungs are over inflated in an effort to move air in and out of the lungs. Blood tests can also detect the virus by showing an elevation of antibodies to fight the virus. One draw back to this is that antibodies in the infant’s blood might have come from the mother at birth. Collecting a nasopharyngeal aspirate is still the most efficient way to determine RSV. “Each year, RSV infections lead to more than 125,000 hospitalizations and about 2,500 deaths”. As stated by Michael H. Nelson, Ph. D., R.Ph “No other human viral infection is as predictable on an annual basis as RSV is, in terms of morbidity, time of outbreak and virulence”.(Nelson pg.1) In my own personal research, this year is a prime example of the high number of infants, which were/are RSV infected. February 2006, all the pediatric critical care beds available in Phoenix, Tucson and El Paso were constantly full of RSV children. These were only the very sickest! Phoenix Children’s Hospital had a 12 to 24 hour wait in their emergency Department to be seen by a physician. Children in Arizona, New Mexico and Southern Texas had to be flown to Colorado, Utah, Oklahoma and Northern Texas for treatment of severe respiratory compromise. Most of these children had a combination of bronchiolitis and pneumonia RSV. This information came from Emergency nurses that I had spoken to in Phoenix, Tucson, Deming, Las Cruces and El Paso. In the many readings on RSV, the biggest concern of researchers is that RSV is a non-retroviral RNA virus. These are broken down into two subgroups as either immunoprophylaxis or antiviral therapy. As seen in the following chart (Nelson pg3), the groups are broken down and as can be seen are very costly for treatment. The other drawback for the two drugs under prevention is subjecting the infant/child to needle sticks for administration of the drug. Table 2: Comparison of Agents for RSV Treatment and Prophylaxis PARAMETER DRUG FDA Indication Ribavirin Treatment of LRI due to RSV1 RSV-IGIV Prevention of LRI in children <24 months old with risk or RSV disease Palivizumab Prevention of LRI in children with risk for RSV disease Administration Route Aerosolization Intravenous Intramuscular Dose 20 mg/mL aerosol 12-18 hours per day 750 mg/kg (15 mL/kg) monthly during RSV season 15 mg/kg monthly during RSV season (divide dose if volume >1 mL) Contraindications Pregnancy or potential for exposure to pregnant individuals Hypersensitivity to products containing IgG History of immunoglobulin A (IgA) deficiency Cyanotic CHD (congenital heart disease) Hypersensitivity to palivizumab Common Side Effects Ventilator dysfunction Pulmonary dysfunction Rash, conjunctivitis (patient & exposed healthcare workers) Headache, lacrimation, pharyngitis (exposed healthcare workers) Infusion-related effects (fluid accumulation in lungs, decrease in O2 saturation) Erythema at injection site Cost2 $5279.40 per course of therapy (300 mL aerosol solution) <3.3 kg: $816.32 >3.3 kg: $1632.64 <3.3 kg: $699.46 >3.3 kg: $1320.77 1Ribavirin capsules are also indicated, in combination with Intron A, for treatment of chronic hepatitis C. 2Cost to pharmacist for 30-days supply (2001 Redbook) Some studies have shown RSV-IGIV “is effective in reducing the incidence and duration of hospitalization and the severity of illness in infants at high risk for RSV disease… Otherwise, adverse effects, including otitis media and rash, were similar in the treatment and control groups (Nelson Pg4).” As in the above clinical trial and a second placebo-controlled, double blind trial the biggest concern seems to be the fluid accumulation in the lungs. The fluid lead to decreased oxygen saturations and were minimized or decreased by adjusting the infusion rate.(Nelson pg4) Another problem is that immunoglobulin administration may inactivate other live vaccines like MMR and Varicella. These vaccines should be given in approximately nine months after RSV-IGIV therapy. Even though there are numerous antivirals on the market today, the only one approved by the FDA is ribavirin (Virazole,ICN). As noted on the previous chart, ribavirin is very costly and hard to work with due to the numerous side effects. “Due to these factors, ribavirin use is generally limited to those patients with severe complications arising from RSV infection.”(Nelson pg6) In other research with ribavirin, they seem to have much of the same results or out-comes from slight benefits to long-term benefits. In one research study by Dr. Rodriguez from Washington D.C., over 7 years using 19 patients using ribavirin and placebo’s showed “53% (7 of 13) of ribavirin treated patients showed normal… conclusion: weighted severity score suggest long-term beneficial effects of ribavirin.(ALA pg5)” Dr. Krilar and his team had done a study of 100 patients from six institutions in a 5-6 year period that had been treated with ribavirin and without their study constituted using medical records and pulmonary function test (PFT) and questionnaires. The results of their findings were, “No significant differences in the PFT’s in the two groups, No evidence of adverse long term effect of ribavirin therapy. (ALA pg 5,6) To a more positive note, researchers at the University of South Florida, wo...