TICKS
How ticks threaten humans and pets
D
ifferent ticks carry
various bacteria
which can cause
diseases in humans, dogs and
cats. When an infected tick
bites a human, the bacterium
is transmitted in the tick's
saliva.
Amblyomma hebraeum
transmits Rickettsia africana,
the cause of African tick-bite
fever in humans. The larvae
of A hebraeum are probably
more responsible than any
other tick for tick bites in
humans. Other ticks that are
It is well-known that ticks can affect
livestock (Smallholder November
2017). But smallholders and our pets
are also at risk because of where we
live.
able to harbour the organism
belong to either the
Amblyomma, Dermacentor or
the Rhipicephalus family of
ticks.
Symptoms may include fever,
headache, muscle pains,
malaise and a rash. At the site
of the bite there is typically a
black eschar (a black mark
where the bite occurred).
Onset usually occurs four to
ten days after the bite.
Symptoms can vary, depend-
ing partly on the organism
involved. Age and underlying
health may also influence the
severity of the infection.
However there is a second,
rarer, form of tick bite fever in
South Africa transmitted by
Rickettsia conorii which is
much more severe, causing
multiple organ problems and
a fever, headache, rash and
even organ failure.
A doctor is likely to make a
diagnosis based on the
patient's symptoms and the
likelihood of having been
bitten by a tick, rather than
relying on the results from
blood tests which take too
long, so the doctor probably
won't even bother to have a
test done.
Where the tick bite fever is
fairly mild, people may get
better on their own without
specific treatment. This can
37
www.sasmallholder.co.za
take up to two weeks
however, and treatment with
an antibiotic can shorten the
duration of symptoms and
reduce the chance of a
serious side-effect.
In severe cases, antibiotic
therapy is more important,
and can be lifesaving.
A good way to prevent tick
bite fever is to avoid being
bitten by ticks ~ difficult if
you enjoy camping and
hiking or if you are working
out in your pastures on your
plot.
However, it helps to cover
exposed skin by wearing
long-sleeved shirts, long pants
and hats. Light coloured
clothing makes it easy to see
ticks. Tuck in shirts, tuck
pants into socks, and wear
closed shoes instead of
sandals to prevent bites.
Continued on page 38