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tube or hypostome (shown orange in the centre of the picture), which has backward<br />
pointing barbs that help secure it in the skin. Just to make sure the tick mouthparts<br />
are firmly attached and do not allow any blood to leak out, the tick secretes a<br />
milky fluid which solidifies around the hypostome forming a cement cone (grey in<br />
the picture). All of this helps explain why it is so tricky to remove a tick once it’s<br />
attached.<br />
Imagine, though, that this had been a splinter wedged in your skin. First, you would<br />
feel a hurtful prick and then your skin would become inflamed and possibly swollen.<br />
Why doesn’t this happen when a tick bites? The reason lies in the tick’s large and<br />
complex salivary glands. These produce the cement fluid and hundreds of other<br />
molecules (proteins, peptides, and small molecules), which are secreted in tick saliva<br />
while the tick attaches and then feeds on blood. Saliva molecules have different<br />
activities that help make ticks invisible to the host’s protective mechanisms, and<br />
keep the blood flowing so they can suck it up. Saliva molecules include anaesthetics,<br />
anti-inflammatories, anticoagulants, and immunomodulators. It’s not surprising<br />
ticks have been called sophisticated pharmacologists. And it’s all in their spit!<br />
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