Successful development of new RSV vaccines will depend on investigations in several areas. Researchers must learn more about natural immunity to RSV infection in infants and adults, and about the possible role of antigenic variants in recurrent RSV infections.
Attempts to purify antigens from viruses grown in tissue culture and to produce intact antigens from cloned DNA fragments should be encouraged.
The health belief model parameters (perceptions of risk of illness, severity, vaccination benefits, and barriers) used to predict vaccine utilization are described in Chapter 6, where scores assigned to various vaccines are displayed together to facilitate comparison.
Parents’ perceptions of RSV illness as a threat to their children have been judged to be moderate to low. In contrast, a high score has been assigned for severity, because the disease often occurs in very young infants. The benefits probably would be viewed as only moderate, because the vaccine may ameliorate but not totally prevent illness. Barriers also would be moderate, and may be somewhat higher for a glycoprotein vaccine if several doses are necessary, as expected.
Provider recognition of RSV as a risk to children is probably higher than that of the public, and accompanied by the realization that the disease is quite severe. Providers are likely to view the benefits (possible amelioration rather than prevention of serious disease) more favorably than parents. Barriers would be moderately high, however, predominantly because of apprehension over administering the vaccines (or any agent) to very young children.
The scope and purpose of the calculations included below are described in Chapters 4 and 7. The calculations are based on certain simplifying procedures and assumptions that have been judged not to compromise their utility for the purposes of this comparison. The total costs should be taken only as an approximation of the direct cost of this disease.