Live vaccine strain

A live vaccine strain of measles (Chapter 15) was introduced in the USA in 1962 and to the UK in 1968. A single injection produces high-level immunity in over 95% of recipients. Moreover, since the vaccine induces immunity more rapidly than the natural infection, it may be used to control the impact of measles outbreaks. The measles virus cannot survive outside ofan infected host. Widespread use ofthe vaccine therefore has the potential, as with smallpox, of eliminating the disease worldwide. Mass immunization has reduced the incidence of measles to almost nil, although a 15-fold increase in the incidence was noted in the USA between 1989 and 1991 because of poor compliance. 

Direct determination of Salmonella live-vaccine strains 220... 

J. Havlasova, L. Hemychova, P. Halada, V. Pellantova, J. Krejsek, J. Stulik, A. Macela, P. R. Jungblut, P. Larsson, and M. Forsman. Mapping of Immunoreactive Antigens of Francisella Tularensis Live Vaccine Strain. Proteomics, 2(2002) 857-867. 

Sebastian, S., Dillon, S.T., Lynch, J.G., Blalock, L.T., Balon, E., Lee, K.T., Comstock, L.E., Conlan, J.W., Rubin, E.J., Tzianabos, A.O., Kasper, D.L. A defined O-antigen polysaccharide mutant of Francisella tularensis live vaccine strain has attenuated virulence while retaining its protective capacity. Infect Immun 75 (2007) 2591-2602. 

Sabin, A.B. Boulger, L. History of sabin attenuated poliovirus oral live vaccine strains. J. Biol. Standardization 1973, i, 115-118. 

A live attenuated Varicella vaccine was developed in 1973 by Takahashi using the Oka strain, which was isolated from a boy with chickenpox and named after the boy. Several producers use this live vaccine strain, for example Biken Institute, Merck, Sharp Dohme, and SmithKline Beecham. Whereas the first Oka strain vaccines needed to be stored at —20°C, subsequent reformulation of the vaccine provided a shelf-life of up to 2 years at -t-2 C, with... 

Faecal excretion of vaccine virus will occur and may last for up to 6 weeks post-treatment. Such released virus will spread to close contacts and infect/(re-)immunize them. Vaccine-associated poliomyelitis may occur through reversion of the attenuated strains to the virulent wild-type, particularly with types II and III and is estimated to occur once per 4 million doses. As the wild-type virus can be isolated in faeces, infection may occur in unimmunized contacts as well as vaccine recipients. Since the introduction of OPV, notifications of paralytic poliomyelitis in the UK have dropped spectacularly. However, from 1985 to 1995,19 of the 28 notified cases of paralytic poliomyelitis were associated with revertant vaccine strains (14 recipients, 5 contacts). As the risk of natural infections with poliomyelitis within developed countries has now diminished markedly, the greater risk resides with the live vaccine strains. Proposals are therefore now being considered that in the developed world OPV should be replaced with IPV. 

Ryd, M., Verma, N. and Lindberg, A.A. (1992) Induction of a humoral immune response to a Shiga toxin B subunit epitope expressed as a chimeric LamB protein in a Shigella flexneri live vaccine strain. Microb Pathog, 12, 399 07. 

The natural tularemia foci in Kazakhstan occupy 552,400 km2 (26% of the territory of the Republic). The most effective method of prophylaxis is vaccination by live vaccine strain Francisella tularensis holarctica (Russian), which provides reliable immunity for 5 years. Annually, between 70,000 and 100,000 people are vaccinated and revaccinated. We have patented the strain F. tularensis mediasiatica KA-29 for creation of a domestic vaccine that is highly immunogenic, non reactogenic, and will induce crossimmunity [9],... 

Duckett NS, Olmos S, Durrant DM, Metzger DW. Intranasal interleukin-12 treatment for protection against respiratory infection with the Francisella tularensis live vaccine strain. Infect Immun 2005 73 2306-2311. 

Cherwonogrodzky JW, Knodel MH, Spence MR. Increased encapsulation and virulence of Francisella tularensis live vaccine strain (LVS) by subculturing on synthetic medium. Vaccine. 1994 12 773-775. 

Fortier AH, Slayter MV, Ziemba R, Meltzer MS, Nacy CA. Live vaccine strain of Francisella tularensis Infection and immunity in mice. Infect Immun. 1991 59 2922-2928. 

Salomonsson E, Kuoppa K, Forslund AL, et al. Reintroduction of two deleted virulence loci restores full virulence to the live vaccine strain of Francisella tularensis. Infect Immun. 2009 77 3424-31. doi 10.1128/1A1.00196-09. 

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