COMBINATION VACCINES
Combination vaccines are immunization products which contain antigens of multiple infectious agents, e.g. DPT or MMR. However, vaccines which contain multiple strains of the same infectious agent, e.g.
PCV, are better described as polyvalent vaccines.Combination vaccines containing two to six antigens are available in India at present (Table 9.3) and many more combination vaccines are being introduced in market.
Main advantage of combination vaccines is less number of pricks and fewer immunization visits with better compliance. However, these vaccines carry potential disadvantage of cumulative risk of adverse events. Human immune system is capable to respond to large number of antigens simultaneously and efficacy of most vaccines is not altered by concurrent administration as combination vaccines.
IAP recommends use of combination vaccines with following caveats:
[*] All licensed combination vaccines have an immunogenicity, efficacy and safety profile similar to separately administered component vaccines;
TABLE 9.3: Combination vaccines available in India
• Multiple vaccines should not be mixed in the same syringe, to prepare indigenous combination vaccine, unless specifically recommended by manufacturers.
9.3