Rubella is a common childhood disease, caused by rubella virus (togavirus),
that may be associated with serious complications and/or death. For example,
rubella during pregnancy may cause congenital rubella syndrome in the infants
of infected mothers.
The impact of measles, mumps, and rubella vaccination on the natural history
of each disease in the United States can be quantified by comparing the maximum
number of rubella cases reported in a given year prior to vaccine use to the
number of cases of each disease reported in 1995. For rubella, 57,686 cases
reported in 1969 compared to 200 cases reported in 1995 resulted in a 99.65%
Extensive clinical trials of rubella virus vaccines, prepared using RA 27/3
strain rubella virus, have been carried out in more than 28,000 human subjects
(approximately 11,000 with MERUVAX (rubella virus vaccine live) II) in the U.S.A. and more than 20 additional
countries. A single injection of the vaccine has been shown to induce rubella
hemagglutination-inhibition (HI) antibodies in 97% or more of susceptible persons.
However, a small percentage (1-5%) of vaccinees may fail to seroconvert after
the primary dose (see also INDICATIONS, Recommended Vaccination Schedule).
Efficacy of rubella vaccine was established in a series of double-blind controlled
field trials which demonstrated a high degree of protective efficacy.4
These studies also established that seroconversion in response to rubella vaccination
paralleled protection from this disease.5
Following vaccination, antibodies associated with protection can be measured
by neutralization assays, HI, or ELISA (enzyme linked immunosorbent assay) tests.
Neutralizing and ELISA antibodies to rubella virus are still detectable in most
individuals 11-13 years after primary vaccination.6,7 See INDICATIONS,
Non-Pregnant Adolescents and Adult Females, for Rubella Susceptibility Testing.
The RA 27/3 rubella strain elicits higher immediate post-vaccination HI, complement-fixing
and neutralizing antibody levels than other strains of rubella vaccine 8-14
and has been shown to induce a broader profile of circulating antibodies including
anti-theta and anti-iota precipitating antibodies.15,16 The RA 27/3
rubella strain immunologically simulates natural infection more closely than
other rubella vaccine viruses.16-18 The increased levels and broader
profile of antibodies produced by RA 27/3 strain rubella virus vaccine appear
to correlate with greater resistance to subclinical reinfection with the wild
virus,16,18-20 and provide greater confidence for lasting immunity.
3. Monthly Immunization Table, MMWR 45(1): 24-25, January 12, 1996.
4. Leibhaber, H.; Ingalls, T.H.; LeBouvier, G.L.; et al: Vaccination With RA
27/3 Rubella Vaccine, Am. J. Dis. Child. 123: 133-136, February 1972.
5. Brown, G.C.; et al: Fluorescent-Antibody Marker for Vaccine-Induced Rubella
Antibodies, Infection and Immunity 2(4): 360-363, 1970.
6. Hillary, I.B.; Griffith, A.H.: Persistence of antibody 10 years after vaccination
with Wistar RA 27/3 strain live attenuated rubella vaccine, Br. Med. J. 280(6231):
7. Unpublished data from the files of Merck Research Laboratories.
8. Fogel, A.; Moshkowitz, A.; Rannon, L.; Gerichter, Ch. B.: Comparative trials
of RA 27/3 and Cendehill rubella vaccines in adult and adolescent females, Am.
J. Epidemiol. 93: 392-398, 1971.
9. Andzhaparidze, O.G.; Desyatskova, R.G.; Chervonski, G.I.; Pryanichnikova,
L.V.: Immunogenicity and reactogenicity of live attenuated rubella virus vaccines,
Am. J. Epidemiol. 91: 527-530, 1970.
10. Freestone, D.S.; Reynolds, G.M.; McKinnon, J.A.; Prydie, J.: Vaccination
of schoolgirls against rubella. Assessment of serological status and a comparative
trial of Wistar RA 27/3 and Cendehill strain live attenuated rubella vaccines
in 13-year-old schoolgirls in Dudley, Br. J. Prev. Soc. Med. 29: 258-261, 1975.
11. Grillner, L.; Hedstrom, C.E.; Bergstrom, H.; Forssman, L.; Rigner, A.;
Lycke, E.: Vaccination against rubella of newly delivered women, Scand. J. Infect.
Dis. 5: 237-241, 1973.
12. Grillner, L.: Neutralizing antibodies after rubella vaccination of newly
delivered women: a comparison between three vaccines, Scand. J. Infect. Dis.
7: 169-172, 1975.
13. Wallace, R.B.; Isacson, P.: Comparative trial of HPV-77, DE-5 and RA 27/3
live-attenuated rubella vaccines, Am. J. Dis. Child. 124: 536-538, 1972.
14. Lalla, M.; Vesikari, T.; Virolainen, M.: Lymphoblast proliferation and
humoral antibody response after rubella vaccination, Clin. Exp. Immunol. 15:
15. LeBouvier, G.L.; Plotkin, S.A.: Precipitin responses to rubella vaccine
RA 27/3, J. Infect. Dis. 123: 220-223, 1971.
16. Horstmann, D.M.: Rubella: the challenge of its control, J. Infect. Dis.
123: 640-654, 1971.
17. Ogra, P.L.; Kerr-Grant, D.; Umana, G.; Dzierba, J.; Weintraub, D.: Antibody
response in serum and nasopharynx after naturally acquired and vaccine-induced
infection with rubella virus, N. Engl. J. Med. 285: 1333-1339, 1971.
18. Plotkin, S.A.; Farquhar, J.D.; Ogra, P.L.: Immunologic properties of RA
27/3 rubella virus vaccine, J. Am. Med. Assoc. 225: 585-590, 1973.
19. Liebhaber, H.; Ingalls, T.H.; LeBouvier, G.L.; Horstmann, D.M.: Vaccination
with RA 27/3 rubella vaccine. Persistence of immunity and resistance to challenge
after two years, Am. J. Dis. Child. 123: 133-136, 1972.
20. Farquhar, J.D.: Follow-up on rubella vaccinations and experience with subclinical
reinfection, J. Pediatr. 81: 460-465, 1972.