Tick-induced allergies: mammalian meat allergy, tick anaphylaxis and their significance

Abstract

Serious tick-induced allergies comprise mammalian meat allergy following tick bites and tick anaphylaxis. Mammalian meat allergy is an emergent allergy, increasingly prevalent in tick-endemic areas of Australia and the United States, occurring worldwide where ticks are endemic. Sensitisation to galactose-α-1,3-galactose (α-Gal) has been shown to be the mechanism of allergic reaction in mammalian meat allergy following tick bite. Whilst other carbohydrate allergens have been identified, this allergen is unique amongst carbohydrate food allergens in provoking anaphylaxis. Treatment of mammalian meat anaphylaxis involves avoidance of mammalian meat and mammalian derived products in those who also react to gelatine and mammalian milks. Before initiating treatment with certain therapeutic agents (e.g., cetuximab, gelatine-containing substances), a careful assessment of the risk of anaphylaxis, including serological analysis for α-Gal specific-IgE, should be undertaken in any individual who works, lives, volunteers or recreates in a tick endemic area. Prevention of tick bites may ameliorate mammalian meat allergy. Tick anaphylaxis is rare in countries other than Australia. Tick anaphylaxis is secondarily preventable by prevention and appropriate management of tick bites. Analysis of tick removal techniques in tick anaphylaxis sufferers offers insights into primary prevention of both tick and mammalian meat anaphylaxis. Recognition of the association between mammalian meat allergy and tick bites has established a novel cause and effect relationship between an environmental exposure and subsequent development of a food allergy, directing us towards examining environmental exposures as provoking factors pivotal to the development of other food allergies and refocusing our attention upon causation of allergy in general.

Amblyomma sculptum tick saliva: α-Gal identification, antibody response and possible association with red meat allergy in Brazil

“…In one study, fish was the major source of allergen, with higher titers of IgE antibody detected in patients (79%) compared with controls (28%) (Naspitz et al, 2004; Sanchez and Sanchez, 2015). Allergies induced by tick bites, in contrast, have only recently been appreciated as a world-wide problem (van Nunen, 2015). The connection between red meat allergy and tick bites was first described in Australia in 2009, in which study the authors correlated 24 of 25 patients with a history of tick bite followed by the development of an allergic response to red meat (Van Nunen et al, 2009).…”

Do Tick Attachment Times Vary between Different Tick-Pathogen Systems?

“…Alpha-gal syndrome is caused in humans when, during blood feeding, ticks expectorate (in saliva) the carbohydrate galactose-α-1,3-galactose (alpha-gal) and antibodies are produced in the human [93].…”

“…In the US, alpha-gal syndrome has become most common in the southeast [93] and meat allergies (e.g., beef, lamb, pork, venison, cow milk) are associated with A. americanum prevalence [94]. It is unknown how long a tick must be attached in order for the alpha-gal sensitivity to occur.…”

“…It is unknown how long a tick must be attached in order for the alpha-gal sensitivity to occur. It is thought that meat allergies would lessen over time if further tick bites were prevented [93]; however, more research must be done to verify this.…”

Mammalian meat allergy

“…It is understood that for IgE to be produced specific to α ‐gal, a provoking agent (tick bite) is needed to generate a state of allergy proneness promoting the development of a Th2 cytokine profile whereby class‐switching to IgE can occur. These IgE antibodies will be specific for either α ‐gal, tick salivary proteins, or both; however, the tendency toward developing the α ‐gal allergy is dependent on individual susceptibility …”