Reuters Health Information: Vaccines do not cause MS, other demyelinating diseases
Vaccines do not cause MS, other demyelinating diseases
Last Updated: 2014-10-20
By Will Boggs MD
NEW YORK (Reuters Health) - Vaccines do not appear to cause
multiple sclerosis or other central nervous system (CNS)
demyelinating syndromes, but they may accelerate the transition
from subclinical to overt disease, according to results from a
nested case-control study.
"Our key takeaway message for clinicians is that our
anecdotal experiences of first onset of MS symptoms shortly
after vaccination do not mean that the vaccination caused the
individual to develop MS," Dr. Annette Langer-Gould from Kaiser
Permanente, Southern California, Pasadena, California told
Reuters Health by email. "Our epidemiological study was able to
detect a short term increased risk but only in younger
individuals and only for the first 30 days after vaccination."
Some earlier studies have suggested an association between
hepatitis B vaccine or human papillomavirus (HPV) vaccine, with
an increased risk of multiple sclerosis (MS) or acquired CNS
demyelinating syndromes (ADS), but the associations remain
Dr. Langer-Gould and colleagues used data from the Kaiser
Permanente Immunization Tracking System to examine in more
detail the association between the first onset of CNS
demyelinating syndromes and vaccines.
As reported October 20th online in JAMA Neurology, their
study included 780 patients with newly diagnosed MS, clinically
isolated syndrome (CIS), or acute disseminated encephalomyelitis
There were no cases of ADS or ADEM within 42 days or one
year of any hepatitis B-containing vaccination and no
association of new-onset MS or CIS in the one to three years
after vaccination with any hepatitis B-containing vaccination.
There was a nonsignificant trend toward an increased risk of
MS (but not CIS or ADEM) within the first three months after HPV
Similarly, there was no association between any vaccination
three years earlier and CNS ADS, although the risk of CNS ADS
was increased 30 days after any type of vaccination in
individuals under age 50.
"However," the researchers say, "this association
disappeared after 30 days, suggesting that, at most, vaccines
are redundant enhancers of preexisting autoimmunity."
For individuals over age 50, there was no association
between any vaccination and CNS ADS during any time interval.
Among the 11 individuals who developed their first symptoms
of MS within 30 days following vaccination, all made a full
recovery from their first attack. Moreover, nine of 12 patients
with optic neuritis or idiopathic transverse myelitis within 30
days after vaccination had no asymptomatic lesions identified on
"We were certainly surprised to detect a temporal
relationship in younger individuals two to four weeks after
vaccination, although in retrospect it makes sense, as this is
what clinicians have been reporting for many years," Dr.
"The short-term increase in risk suggests that vaccines may
accelerate the transition from subclinical to overt autoimmunity
in patients with existing disease," the researchers say.
"The important thing for these individuals to know is that
if they develop neurological symptoms that are continuous and
last more than 24 hours, they should seek medical care and
request to be evaluated by a neurologist, as multiple sclerosis
is often a difficult diagnosis for non-neurologists to make,"
Dr. Langer-Gould advised.
She added, "Answering the question of vaccine safety and the
risk of MS is difficult and requires large numbers of
individuals, carefully collected clinical information, and many
studies. For newer vaccines like HPV that only recently started
to be given to boys, we and other researchers need to continue
to gather and share data."
Dr. Jorge Correale from Raul Carrea Institute for
Neurological Research, Foundation for the Fight against Infant
Neurological Illnesses, Buenos Aires, Argentina has published
widely on multiple sclerosis. He told Reuters Health by email,
"These data are in agreement with our previous review and
meta-analysis conducted in our Center by Dr. Mauricio Farez."
"Years ago a French report communicated that hepatitis B
vaccination can induce MS," he noted. "However, no other series
reproduced these findings, and today the MS community assumes
that this vaccine does not increase the risk of MS. This was
also reported in our previous communication."
Dr. Correale added, "We report some few, but serious, cases
of exacerbation of MS after vaccination with yellow fever
vaccine. Therefore, we do not recommend to use this vaccine in
patients with an established diagnosis of MS, and of course, we
discussed in depth with the patient risk versus benefits of
vaccine if he/she must travel to an endemic area."
JAMA Neurol 2014.