Live influenza vaccines

Influenza virus vaccine live intranasal-medimmune vaccines CATV-T, influenza vaccine live intranasal. Dmgs R D 2003, 4 (5), 312-319. 

Influenza vaccine, live + Antivirals active against influenza... 

Healthy individuals 5 to 49 years of age can receive the live attenuated influenza vaccine instead of the inactivated vaccine. There are limited data on transmission of the vaccine strain following intranasal vaccination however, secondary transmission does not appear to be a concern. 

Household contacts of immunocompromised persons should have all routine vaccines as scheduled, including yearly influenza vaccination. Children in the household may receive live virus vaccines without special precautions however, if a rash develops following varicella vaccination, contact should be avoided with the immunocompromised host until the rash resolves. 

The two vaccines currently available for prevention of influenza are the trivalent influenza vaccine (TIV) and the live-attenuated influenza vaccine (LAIV). The specific strains included in the vaccine each year change based on antigenic drift. 

LAIV, live-attenuated influenza vaccine TIV, trivalent influenza vaccine. 

Comparison of Trivalent (TIV) and Live-Attenuated Influenza Vaccine (LAIV)... 

Influenza vaccine. (Minimum age 6 months for trivalent inactivated influenza vaccine [HVJ 5 years for live, attenuated influenza vaccine [IAIZ])... 

Inactivated vaccines are generally acceptable (e.g, pneumococcal, meningococcal, and influenza [trivalent inactivated influenza vaccine]), and live vaccines generally are avoided in persons with immune deficiencies or immune suppressive conditions. Information on specific conditions is available at vwvw.cdc.gov/vaccines/pubs/acip-list.htm. 

Influenza Virus Vaccine, Live, Intranasal (FluMist)... 

Attenuated live vaccines are less common than they were a century ago, examples being the original Pasteur rabies vaccine and BCG, but the recent approval of a nasal influenza vaccine, FluMist (Medlmmune Vaccines, Inc., Gaithersburg, MD) shows that the approach remains valid. 

Cholera vaccines are produced by inactive bacteria and are administered subcutaneously, intramuscularly, or intradermally. Cholera vaccines should not be administered intradermally in children less than 5 years of age. The vaccination is particularly indicated for people living in highly endemic areas, as well as laboratory and medical personnel exposed to Vibrio cholerae. Diphtheria tetanus pertussis (DTP) vaccine can be made either as toxoids or inactivated whole bacteria. Hemophillus influenzae vaccine is a bacterial polysaccharide conjugated to proteins and is given as one intramuscular dose. A booster dose is not recommended. This vaccine is given to all children in cases such as plenia and other at-risk condiUons. 

Influenza. Although current influenza vaccine (subunit split vaccine) has been in use yearly for the elderly, it is not recommended for the general population or infants. Improvements to increase or prolong the immunogenicity, reduce the side-effects (due to egg production procedure), and provide mass protection are still being pursued. One approach is to use a live, attenuated vims though cold adaptation. A vaccine has been used in Russia and demonstrated to be safe and efficacious for infants (82). Clinical trials for a similar vaccine are being carried out in the United States (83). 

Influenza vaccines EMEA points to consider on the development of live attenuated influenza vaccines 2003... 

Influenza vaccine viruses are propagated in embryonated chicken eggs. The virus-containing extra-embryonic fluid is harvested, purified, and inactivated with formalin. Inactivated flu vaccine is produced either as whole virus vaccine or ether-disrupted split or subunit preparations. However, many other new or modified influenza vaccines are already available or are expected to appear in the near future, for example vaccines containing new adjuvants, live attenuated vaccines, and vaccines administered by alternative routes. 

In a randomized, double-blind study, trivalent, live, attenuated, cold-adapted intranasal influenza vaccine (FluMist) has been compared with intranasal placebo plus a trivalent injected inactivated influenza vaccine (5). The 200 patients were aged 65 years and over and had chronic cardiovascular or pulmonary conditions or diabetes mellitus. During the 7 days after immunization, sore throat was reported on at least one day by significantly more of the FluMist recipients (15 versus 2%). The increased frequency of sore throat may have been attributable to direct or indirect effects of vaccine virus replication. No other symptom was associated with FluMist. These findings were consistent with evaluations of other live, attenuated, cold-adapted influenza vaccine formulations in older adults. However, further studies of the safety of FluMist are warranted. 

Jackson LA, Holmes SJ, Mendelman PM, Huggins L, Cho I, Rhorer J. Safety of a trivalent live attenuated intranasal influenza vaccine, FluMist, administered in addition to parenteral trivalent inactivated influenza vaccine to seniors with chronic medical conditions. Vaccine 1999 17(15-16) 1905-9. 

The single-component viral vaccines are listed in Table 23.2 with notes similar to those provided with the bacterial vaccines. The only combined viral vaccine that is widely used is the measles, mumps and rubella vaccine (MMR Vac). In a sense however, both the inactivated (Salk) poliovaccine (Pol/Vac (inactivated)) and the live (Sabin) polio-vaccine (Pol/Vac (oral) are combined vaccines in that they are both mixtures of virus of each of the three serotypes of poliovirus. Influenza vaccines, too, are combined vaccines in that they usually contain components from several virus strains, usually from two strains of influenza A and one strain of influenza B. 

Clinically important, potentially hazardous interactions with aluminum, aminophylline, aspirin, chlorambucil, cimetidine, clarithromycin, cyclophosphamide, cyclosporine, dicumarol, diuretics, docetaxel, estrogens, grapefruit juice, indomethacin, influenza vaccines, itraconazole, ketoconazole, lansoprazole, live vaccines, methotrexate, montelukast, omeprazole, oral contraceptives, pancuronium, phenobarbital, phenytoin, ranitidine, rifampicin, rifampin, timolol, tolbutamide, vitamin A... 

Biological sources are primarily used for vaccines. Vaccines are suspensions of living or killed micro-organisms, components or products thereof. They are produced in living systems. Eggs are the most widely used medium at present, notably for influenza vaccines, but there is increasing use of animal cell cultures. Bacterial vaccines, for example, the diphtheria vaccine, can be cultured. There is an overlap here with fermentation processes (Section II.D.). 

Gruber WC. The role of live influenza vaccines in children. Vaccine 2002 20(suppl 2) S66-73. 

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