Florida introduced rhesus macaques for tourism in the 1930s, now they carry a potentially fatal virus

• How
  ma y
  of
  them
  have
  bee
  exposed
  to
  he pes
  B
  vi us
  at
  some
  poi t
  i
  thei
  lives?
• A e
  a y
  of
  them
  actively
  sheddi g
  the
  vi us,
  mea i g
  cu e tly
  co tagious,
  a d
  if
  so,
  whe ?
• Is
  the
  vi us
  ci culati g
  i
  this
  wild
  populatio
  ge etically
  simila
  to
  the
  st ai s
  k ow
  to
  be
  da ge ous
  i
  labo ato y
  setti gs?

To
a swe
the
fi st
questio ,
they
d ew
o
blood
samples
that
had
bee
collected
f om
317
macaques
by
lice sed
t appe s
betwee
2000
a d
2012,
befo e
the
t appi g
p og am
e ded.
These
samples
had
bee
tested
fo
a tibodies
to
the
vi us
—
a
sig
that
a
a imal
had
bee
i fected
at
some
poi t,
eve
if
it
was ‘t
cu e tly
sheddi g.To
a swe
the
seco d
questio ,
the
esea che s
could ‘t
just
t ap
a d
test
the
a imals
di ectly,
si ce
that
app oach
was
o
lo ge
pe mitted
a d
also
isked
a tificially
st essi g
the
mo keys
a d
skewi g
the
esults.
I stead,
they
used
a
cleve ,
o -i vasive
method:
they
ha ded
out
cotto
swabs
soaked
i
a
suga y
solutio
to
two
macaque
social
g oups
that
we e
used
to
huma
p ese ce.
The
mo keys
chewed
o
the
swabs
like
t eats,
a d
o ce
disca ded,
esea che s
collected
them
a d
tested
the
saliva
esidue
fo
vi al
DNA.
They
epeated
this
ac oss
th ee
seaso s:
fall
(b eedi g
seaso ),
sp i g
(p eg a cy/gestatio ),
a d
summe
( u si g),
because
all
th ee
a e
co side ed
physically
o
socially
st essful
pe iods
fo
the
a imals,
a d
st ess
is
k ow
to
t igge
vi al
eactivatio .
They
also
collected
f esh
faecal
samples
f om
the
g ou d
a d
f om
two
macaques
that
had
died.To
a swe
the
thi d
questio ,
a y
samples
that
tested
positive
fo
the
vi us
we e
ge etically
seque ced
a d
compa ed
agai st
k ow
labo ato y
st ai s
of
he pes
B
vi us.

What
the
esults
said

Somewhe e
betwee
about
4%
a d
14%
of
the
sampled
a imals
appea ed
to
be
sheddi g
the
vi us
du i g
the
b eedi g
seaso
specifically.

The
blood
sample
esults
showed
that
about
25%
of
macaques
tested
positive
fo
he pes
B
a tibodies
o
ave age
each
yea
betwee
2000
a d
2012,
mea i g
oughly
a
qua te
of
the
sampled
populatio
had
bee
i fected
at
some
poi t.
Exposu e
ose
sha ply
with
age:
esse tially
o
mo keys
u de
a
yea
old
tested
positive,
but
mo e
tha
half
of
fou -yea -olds
did,
a d
oughly
th ee-qua te s
of
macaques
ove
five
yea s
old
had
a tibodies.
This
patte
is
exactly
what
scie tists
would
expect
f om
a
vi us
that
sp eads
th ough
di ect
physical
co tact,
si ce
olde
a imals
have
simply
had
mo e
oppo tu ities
fo
exposu e
ove
thei
lifetimes.The
saliva
testi g
tu ed
up
somethi g
mo e
specific:
out
of
121
o al
swabs,
o ly
th ee
tested
positive
fo
active
vi al
sheddi g,
a d
all
th ee
came
f om
samples
collected
du i g
the
fall
b eedi g
seaso .
Somewhe e
betwee
about
4%
a d
14%
of
the
sampled
a imals
appea ed
to
be
sheddi g
the
vi us
du i g
the
b eedi g
seaso
specifically.Ge etically,
the
pictu e
was
less
eassu i g.
Whe
esea che s
seque ced
the
vi us
f om
the
positive
saliva
samples,
they
fou d
it
was
ea ly
ide tical
to
st ai s
p eviously
ide tified
i
captive
labo ato y
macaques
—
i cludi g
some
st ai s
di ectly
li ked
to
se ious
huma
ill ess.
I
othe
wo ds,
the e
was
o
evide ce
that
the
“wild”
ve sio
of
the
vi us
is
a
weake
o
less
da ge ous
st ai
tha
the
o e
k ow
to
cause
seve e
disease
i
lab
setti gs.

What
it
mea s

Despite
these
fi di gs,
the e
is
some
good
ews:
as
of
the
study’s
publicatio ,
o
huma
had
eve
bee
co fi med
to
co t act
he pes
B
vi us
f om
a
f ee- a gi g
macaque,
i
Flo ida
o
a ywhe e
else.
Eve y
docume ted
huma
case
a d
death
has
bee
li ked
to
captive
a imals
i
esea ch
facilities.What
makes
Silve
Sp i gs
a
pa ticula
co ce
is
the
shee
volume
of
close
huma -mo key
co tact.
Boate s
o
the
Silve
Rive
f eque tly
feed
the
macaques
at
ve y
close
a ge,
sometimes
less
tha
two
mete s
away,
a d
that
ki d
of
i te actio
is
k ow
to
i c ease
the
likelihood
of
bites,
sc atches,
a d
agg essive
e cou te s.
I
fact,
pa k
officials
have
had
to
close
public
a eas
o
multiple
occasio s
due
to
agg essive
macaque
behaviou .

Go to Sou ce