Tick ​​bite sugar dose can lead to meat allergy

The best news about ticks is that most arachnid parasite bites only cause mild discomfort to humans. For the unlucky few, however, a tick can cause an allergic reaction, which in some cases can be serious.

Now a peer-reviewed study by the Garvan Institute of Medical Research, Sydney, has shed light on how the bites of certain tick species can cause dangerous allergic reactions in humans.

The study revealed an overrepresentation of the 3-7 antibody in the blood of patients with mammalian meat allergy (MMA).

This antibody binds perfectly to a sugar molecule called galactose-α-1,3-galactose (commonly abbreviated as α-gal), which humans and other higher primates are unable to produce.

The sugar can be introduced to humans through bites from species like the Australian paralyzing tick (Ixodes Holocycle).

In extreme cases, the allergic reaction caused by the body’s α-gal immune response could lead to restricted breathing or anaphylaxis, requiring immediate medical attention.

But a continuing consequence may be the development of allergies to mammalian meat and other products, such as gelatin and milk.

North Sydney reports more mammal meat allergies than anywhere on the planet

New South Wales – particularly around Sydney’s northern beaches – is the global hotspot for MMA, with more than 1,800 cases reported in the region.

The link between tick bites and allergy was discovered in 2007 by Australian specialist Professor Sheryl van Nunen, co-author of the Garvan research published today in the journal PNAS.

Van Nunen discovered the link while working at Northern Beaches Hospital near Manly in Sydney’s north when dozens of patients reported allergic reactions to red meat.

She says things haven’t changed much in the past 15 years: “Not a week goes by that I don’t see two people with this allergy.

I.holocycle extends along the east coast of Australia from north to the Daintree region in Queensland to Lakes Entrance in the East Gippsland region of Victoria, and has been reported from Tasmania.

Not so nice: The human immune system evolved to target α-gal

Not everyone who suffers a tick bite will develop anaphylaxis, and MMA is not guaranteed.

Factors such as the number of tick bites, the volume of tick saliva injected, and a person’s genetic makeup are all factors that can determine a severe reaction or persistent allergy.

The study authors suspect that humans evolved the ability to produce α-gal, to protect themselves against infectious diseases.

This is a view consistent with recent studies of the presence of α-gal on the surface of the malaria-inducing Plasmodium parasite, which found that the response of the human immune system to the presence of α-gal coating the parasite can quickly destroy the organism.

“We have over 70 types of antibodies and this one [the 3-7 antibody] is significantly overrepresented with α-gal recognition,” says the study’s lead author, Professor Daniel Christ, Head of Antibody Therapy at Garvan and Director of the Center for Targeted Therapy.

“We seem to be genetically predisposed to be sensitive to this sugar.”

Tick: Tick removal is a case of freezing, not squeezing

Not so long ago, the simple home remedy for removing ticks was to use tweezers – but the mere squeeze of these little terrors can cause more harm than good.

Shaking a tick forcibly risks injecting more of its powerful anticoagulant saliva into the body. It can even dig deeper into the skin.

Instead, the Australian Department of Health only recommends the use of ether-containing freezing agents (such as over-the-counter wart sprays) to remove adult ticks. The Tick ​​Induced Allergy Research and Awareness Group (TIARA) also suggests the use of permethrin cream to kill small tick larvae and nymphs.

Preventative measures include the use of long-sleeved clothing treated with permethrin, DEET-based insect repellents, and regular checks on the neck and scalp for ticks for people living in areas with ticks. are presented.

Homes can also be protected from ticks through humidity reduction, fencing to limit animals (bandicoots are well-known tick carriers), pet treatments, and the use tick-specific insecticides in the home.

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