Levin LI, Munger KL, Rubertone MV, et al.
JAMA. 2003;289(12):1533-1536
The Epstein-Barr virus (EBV) would win the prize for most
versatile virus if Academy Awards were given to microbes. Both
acute and chronic infections produce a wide variety of
symptoms from minor illness to fulminant malignancy. The
repertoire of the virus is extended to chronic neurologic
disease in this brief report by investigators at the Walter
Reed Army Institute of Research and collaborators at the
Harvard School of Public Health and Virolab Inc. (Berkeley,
California). The investigators showed a relationship between
titer of serum IgG antibodies to viral capsid antigen (VCA) or
EBV nuclear antigen (EBNA) complex and subsequent diagnosis of
multiple sclerosis (MS). The relative risk is plausible,
graded, and substantial. Although not proving causation, this
study suggests the possibility of new ideas to prevent and
treat multiple sclerosis.
The investigators used the
extensive US Defense Department serum bank, which contains
samples from more than 3 million persons collected at entry
into service and approximately every 2 years starting in 1988.
They identified cases of MS (defined as certain or probable on
the basis of diagnostic criteria that included MRI and
examination by a neurologist) from records of the US Army
Disability Agency. Cases were each matched to 2 controls by
age, sex, race/ethnicity, and date of blood draw. Samples were
subjected to IgG and IgA antibody tests for VCA, anti-early
antigen complex (EA-D and EA-R), and IgG antibodies against
EBNA complex and EBNA-1 and EBNA-2. IgG antibodies to
cytomegalovirus (CMV) were also measured in all cases and
controls. Finally, cases and controls were compared using
geometric mean antibody titers against all of the antigens.
There were 83 cases and 166 controls. All cases and 98% of
the controls had evidence of exposure to EBV at entry into the
service. Mean age of onset of MS was 27 years, with diagnosis
considered certain in 64% and probable in 36%. A mean of 4
years elapsed between first blood draw and onset of illness.
The baseline geometric VCA and EBNA complex IgG antibody
levels were significantly higher in cases than in controls.
Additionally, the risk of MS rose significantly as the titer
increased. The relative MS risk of subjects with highest
compared to lowest VCA and EBNA IgG titers were 19.7 and 33.9,
respectively. There was no association of risk to CMV
antibodies, race, age, or sex. Using simultaneous regression
analysis, only high EBNA complex antibody and EBNA-1 antibody
correlated to risk. Interestingly, the VCA and EBNA antibody
levels remained stable across time, even after the onset of
disease.
The investigators state that the pattern of high VCA, high
EBNA seen in the patients with MS suggests recent EBV
infection or reactivation with vigorous cellular immune
response. They also suggest that this pattern has been
associated with greater risk of Hodgkin's disease and
nasopharyngeal cancer. Could the high titer represent
continued viral replication in the central nervous system?
With new anti-herpes medications potentially achieving
sufficient activity against EBV in the central nervous system,
it might be time to see whether anti-EBV therapy is beneficial
for this dreaded disease. On the other hand, it increasingly
looks like a vaccine against EBV given early in childhood
might be a good thing.
Weber DJ, Sickbert-Bennett E, Gergen MF, Rutala WA
JAMA. 2003;289(10):1274-1277
What works for most organisms does not apparently work for
anthrax, at least according to this study by investigators at
the University of North Carolina. Concerned about the best
means of removing spores of
Bacillus anthracis from
hands of first responders, they tested a number of
commercially available hand hygiene products in normal
volunteers challenged by remarkably heavy hand contamination
with a surrogate,
B astroophaeus. Surprisingly, the
best agent was simple soap and water, while 61% ethyl alcohol
spray was completely ineffective.
Four agents (soap and
water, 2% chlorhexidine gluconate, chloride-soaked towel, and
a waterless rub containing 61% ethyl alcohol) used to
eradicate hand contamination were evaluated. Each application
was performed 3 times with each agent, but at different
duration of washing (10 seconds, 30 seconds, or 60 seconds).
Each subject was allowed to participate in no more than 2
trials of 3 washes with 1 agent, 1 duration. Hands were
contaminated by pouring 5 mL of 2.2 x 106 spores/mm3
into cupped hands, then spreading over the entire hands below
the wrist for 45 minutes. Baseline contamination and residual
contamination were determined by massaging hands in rubber
gloves for 60 seconds, then culturing a 5-mL rinse of the
inside of the glove.
There appeared to be little difference between washing with
most agents 1, 2, or 3 times, and no improvement with greater
duration of washing except with the chlorine towel. The best
single agent was soap and water for 10 seconds, which removed
more than 2 logs of spores. The ethyl alcohol was useless no
matter how many times or how long it was used.
The investigators offer a "1B" recommendation that all
first responders and healthcare workers potentially exposed to
anthrax wear gloves and decontaminate with plain soap and
water. Although this is not expected, it certainly makes
things easier than trying to find a special product.