Blood, 1 May 2002, Vol. 99, No. 9, pp. 3486-3487
CORRESPONDENCE
To the editor:
Safety of early immunization against
measles/mumps/rubella after bone marrow
transplantation
Machado et al recently reported on their experience of an
outbreak of measles in Brazil and its impact on their bone marrow transplantation (BMT) population.1 They comment
that one of the major reasons these patients were not immunized is that
fewer than 2 years had passed since receiving BMT, and no
data are available concerning the safety and effectiveness of measles
immunization before the second year after BMT. This is
despite a national study of immunization practices following allogeneic
BMT in the United States, which indicated that the measles, mumps, and
rubella (MMR) immunization was being administered at 12 months or
earlier after BMT in 22% of centers performing
transplantions on children younger than 7 years of age, and
in 12% of centers performing transplantions on children aged
7 years or older.2 As we dealt with a pediatric population, we were concerned that our BMT recipients were vulnerable to infection with measles during the 2-year interval between BMT and
the time recommended for MMR vaccination. This was illustrated when one
of our patients developed measles at 9 months after BMT. We therefore
initiated a protocol firstly of catch-up immunization in patients who
had not been previously immunized, and then of offering immunization
against MMR in the second year after BMT.
We reviewed our experience at the BMT follow-up clinic at the
Children's Hospital Westmead (CHW) with MMR vaccination after BMT. We
have immunized 79 patients with a live attenuated trivalent vaccine
directed against MMR (0.5 mL MMR-II, Merck Sharpe and Dohme, Sydney,
Australia) since November 1990. MMR was administered at a
median time of 13 months after BMT. To be eligible for MMR immunization, patients had to be recipients of either
autografts or allografts who were more than 12 months after BMT,
without cGvHD, and off all immunosuppressives for at least 3 months. One child vaccinated 24 months after allogeneic BMT developed a
transient rash and fever one week after vaccination. He suffered no
serious complications. None of the other 78 patients who were
vaccinated suffered any adverse consequences.
By the time of immunization, patients had infrequent visits to CHW, and
so adequate prevaccination and postvaccination serology results were
available on only 44 patients. Immunization against rubella was
effective from 12 months after BMT onwards. Of the 34 patients
seronegative to rubella prior to immunization, 91% became seropositive
after MMR immunization. Of the 35 patients seronegative to measles
prior to immunization, 16 (46%) became seropositive after MMR
immunization. There was a significantly higher rate of seroconversion
to measles in children who were immunized at more than 15 months after
BMT (35% prior to versus 78% after 15 months; Fisher exact,
P = .05). There was no significant relationship between
seroconversion to measles or rubella and any of the following
variables: age, sex, diagnosis, prior GVHD, or type of BMT donor.
In our experience, MMR vaccination between 12 and 24 months after BMT
is safe. It provides effective immunity against rubella; the 91% rate
of seroconversion to rubella is comparable to rates of 75% and 90%
previously reported. The overall rate of seroconversion to measles of
46% is unsatisfactory but indicates that MMR vaccination is effective
against measles in some children in the second year following BMT. We
are routinely recommending MMR reimmunization at 15 months after BMT,
and it can be safely given earlier if measles or rubella is in the
community. However, serology should be performed following vaccination
to confirm effective immunization against measles.
Peter J. Shaw, Marie Bleakley, and Margaret Burgess
Correspondence: Peter J. Shaw, Oncology, The Children's
Hospital at Westmead, Sydney NSW 2145, Australia; e-mail:
peters{at}nch.edu.au
References
1.
Machado CM, Goncalves FB, Pannuti CS, Dulley FL, de Souza VA.
Measles in bone marrow transplant recipients during an outbreak in Sao Paulo, Brazil.
Blood.
2002;99:83-87[Abstract/Free Full Text].
2.
Henning K, White M, Sepkowitz K, Armstrong D.
A national survey of immunization practices following allogeneic bone marrow transplantation.
JAMA.
1997;277:1148-1151[Abstract]
