Associate Professor Sheryl van Nunen | |
---|---|
Nationality | Australian |
Alma mater | University of Sydney |
Scientific career | |
Fields | Immunologist |
Institutions | University of Sydney |
Sheryl van Nunen is an Australian allergy researcher and Senior Staff Specialist in the Department of Clinical Immunology and Allergy at Royal North Shore Hospital in Sydney, Australia, and Clinical Associate Professor at the Sydney Medical School - Northern, University of Sydney.
Van Nunen, a specialist in allergies, [1] is widely recognized for her work in 2007 identifying tick-induced mammalian meat allergy, [2] [3] [4] which has increased in prevalence worldwide since then. [5] In 2007 she was the first immunologist in the world to describe in a published paper the link between ticks and meat allergy. [6] [7] [8] According to van Nunen, Australia has the highest rate of mammalian meat allergy and tick anaphylaxis in the world. [9]
In 2018, after four years in development, van Nunen, in collaboration with a pharmaceuticals company and northern Sydney hospital Emergency Department, released a world-first freeze spray designed to be topically applied to ticks that have attached to humans. The spray kills ticks by freezing, rather than by the traditional method of removal using tweezers. Removing ticks by tweezers was found to have a significantly detrimental effect because tweezers squeeze toxins from the tick into the host and thereby significantly increase the allergen injected. [10] [11] A study released in 2019 [12] by van Nunen supports the growing consensus in Australia to kill the tick in situ rather than pull the tick out. [13] [14]
Van Nunen had been working at a practice in a tick-prone area of Sydney, when some patients reported having allergic reactions to red meat after being bitten by ticks in their local areas. [2]
Some patients developed allergies to sugar molecule alpha galactose, more commonly known as alpha-gal, which is commonly found in meat and animal products e.g. cow's milk and gelatine. [2]
"Mammalian meat allergy will only come up under certain circumstances, so it's an anytime but not an every time allergy," van Nunen said. [2] "This is one of the problems with diagnosis." [2]
Van Nunen advises that tick anaphylaxis and mammalian meat allergy is preventable if one deals appropriately with the ticks. Preventative measures can also be applied by regularly treating your lawns and dressing appropriately to minimize your risk of exposure to ticks. [2]
Van Nunen advises that mammalian-meat allergy is a rare condition, albeit that she has managed hundreds of cases to date. [15] “After you’ve seen a couple of people and the story’s the same, I like to know what’s happening to them, so I always take a family history of allergy,” she says. [15] These patients said they had experienced a large, localized reaction, or a more extreme systemic reaction, when they’d been bitten by a tick. [15]
When more and more patients presented presenting with similar symptoms, it quickly became clear that it was a tick causing these significant reactions in patients. [15] The tick causing these significant reactions in patients can be found in the Northern Beaches areas. [15]
The tick deploys a unique strategy to maintain attached to its host for an extended period of time, thereby going unnoticed. [15] The tick remains undetectable by using its saliva, which contains anticoagulants, ensuring uninterrupted blood flow, which numbs the surrounding skin, suppresses the host's immune response, preventing any inflammatory reactions, thereby remaining undetectable for extended periods of time. [15]
In August 2020 van Nunen urged sufferers of hay fever to get tested for COVID-19. [16]
In 2021 van Nunen was awarded the Order of Australia Medal for service to medicine, particularly to clinical immunology and allergy. [17] [18]
Allergies, also known as allergic diseases, are various conditions caused by hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic dermatitis, allergic asthma, and anaphylaxis. Symptoms may include red eyes, an itchy rash, sneezing, coughing, a runny nose, shortness of breath, or swelling. Note that food intolerances and food poisoning are separate conditions.
Anaphylaxis is a serious, potentially fatal allergic reaction and medical emergency that is rapid in onset and requires immediate medical attention regardless of the use of emergency medication on site. It typically causes more than one of the following: an itchy rash, throat closing due to swelling that can obstruct or stop breathing; severe tongue swelling that can also interfere with or stop breathing; shortness of breath, vomiting, lightheadedness, loss of consciousness, low blood pressure, and medical shock. These symptoms typically start in minutes to hours and then increase very rapidly to life-threatening levels. Urgent medical treatment is required to prevent serious harm and death, even if the patient has used an epipen or has taken other medications in response, and even if symptoms appear to be improving.
A food allergy is an abnormal immune response to food. The symptoms of the allergic reaction may range from mild to severe. They may include itchiness, swelling of the tongue, vomiting, diarrhea, hives, trouble breathing, or low blood pressure. This typically occurs within minutes to several hours of exposure. When the symptoms are severe, it is known as anaphylaxis. A food intolerance and food poisoning are separate conditions, not due to an immune response.
Tick-borne diseases, which afflict humans and other animals, are caused by infectious agents transmitted by tick bites. They are caused by infection with a variety of pathogens, including rickettsia and other types of bacteria, viruses, and protozoa. The economic impact of tick-borne diseases is considered to be substantial in humans, and tick-borne diseases are estimated to affect ~80 % of cattle worldwide. Most of these pathogens require passage through vertebrate hosts as part of their life cycle. Tick-borne infections in humans, farm animals, and companion animals are primarily associated with wildlife animal reservoirs. Many tick-borne infections in humans involve a complex cycle between wildlife animal reservoirs and tick vectors. The survival and transmission of these tick-borne viruses are closely linked to their interactions with tick vectors and host cells. These viruses are classified into different families, including Asfarviridae, Reoviridae, Rhabdoviridae, Orthomyxoviridae, Bunyaviridae, and Flaviviridae.
Allergen immunotherapy, also known as desensitization or hypo-sensitization, is a medical treatment for environmental allergies and asthma. Immunotherapy involves exposing people to larger and larger amounts of allergens in an attempt to change the immune system's response.
The jack jumper ant, also known as the jack jumper, jumping jack, hopper ant, or jumper ant, is a species of venomous ant native to Australia. Most frequently found in Tasmania and southeast mainland Australia, it is a member of the genus Myrmecia, subfamily Myrmeciinae, and was formally described and named by British entomologist Frederick Smith in 1858. This species is known for its ability to jump long distances. These ants are large; workers and males are about the same size: 12 to 14 mm for workers, and 11 to 12 mm for males. The queen measures roughly 14 to 16 mm long and is similar in appearance to workers, whereas males are identifiable by their perceptibly smaller mandibles.
Peanut allergy is a type of food allergy to peanuts. It is different from tree nut allergies, because peanuts are legumes and not true nuts. Physical symptoms of allergic reaction can include itchiness, hives, swelling, eczema, sneezing, asthma attack, abdominal pain, drop in blood pressure, diarrhea, and cardiac arrest. Anaphylaxis may occur. Those with a history of asthma are more likely to be severely affected.
Ixodes holocyclus, commonly known as the Australian paralysis tick, is one of about 75 species in the Australian tick fauna and is considered the most medically important. It can cause paralysis by injecting neurotoxins into its host. It is usually found in a 20-kilometre wide band following the eastern coastline of Australia. Within that range, Ixodes holocyclus is the tick most frequently encountered by humans and their pets. Because the same area includes Australia's most densely populated regions, bites on people, pets and livestock are relatively common.
Soy allergy is a type of food allergy. It is a hypersensitivity to ingesting compounds in soy, causing an overreaction of the immune system, typically with physical symptoms, such as gastrointestinal discomfort, respiratory distress, or a skin reaction. Soy is among the eight most common foods inducing allergic reactions in children and adults. It has a prevalence of about 0.3% in the general population.
Milk allergy is an adverse immune reaction to one or more proteins in cow's milk. Symptoms may take hours to days to manifest, with symptoms including atopic dermatitis, inflammation of the esophagus, enteropathy involving the small intestine and proctocolitis involving the rectum and colon. However, rapid anaphylaxis is possible, a potentially life-threatening condition that requires treatment with epinephrine, among other measures.
Egg allergy is an immune hypersensitivity to proteins found in chicken eggs, and possibly goose, duck, or turkey eggs. Symptoms can be either rapid or gradual in onset. The latter can take hours to days to appear. The former may include anaphylaxis, a potentially life-threatening condition which requires treatment with epinephrine. Other presentations may include atopic dermatitis or inflammation of the esophagus.
A tree nut allergy is a hypersensitivity to dietary substances from tree nuts and edible tree seeds causing an overreaction of the immune system which may lead to severe physical symptoms. Tree nuts include almonds, Brazil nuts, cashews, chestnuts, filberts/hazelnuts, macadamia nuts, pecans, pistachios, shea nuts and walnuts.
Insect sting allergy is the term commonly given to the allergic response of an animal in response to the bite or sting of an insect. Typically, insects which generate allergic responses are either stinging insects or biting insects. Stinging insects inject venom into their victims, whilst biting insects normally introduce anti-coagulants into their victims.
Ixodes ricinus, the castor bean tick, is a chiefly European species of hard-bodied tick. It may reach a length of 11 mm (0.43 in) when engorged with a blood meal, and can transmit both bacterial and viral pathogens such as the causative agents of Lyme disease and tick-borne encephalitis.
Thomas Alexander Evelyn Platts-Mills, FRS, son of British member of parliament and barrister John Platts-Mills, is a British allergy researcher and director of the Division of Allergy and Clinical Immunology at the University of Virginia School of Medicine.
Amblyomma americanum, also known as the lone star tick, the northeastern water tick, or the turkey tick, is a type of tick indigenous to much of the eastern United States and Mexico, that bites painlessly and commonly goes unnoticed, remaining attached to its host for as long as seven days until it is fully engorged with blood. It is a member of the phylum Arthropoda, class Arachnida. The adult lone star tick is sexually dimorphic, named for a silvery-white, star-shaped spot or "lone star" present near the center of the posterior portion of the adult female shield (scutum); adult males conversely have varied white streaks or spots around the margins of their shields.
Fluticasone furoate, sold under the brand name Flonase Sensimist among others, is a corticosteroid for the treatment of non-allergic and allergic rhinitis administered by a nasal spray. It is also available as an inhaled corticosteroid to help prevent and control symptoms of asthma. It is derived from cortisol. Unlike fluticasone propionate, which is only approved for children four years and older, fluticasone furoate is approved in children as young as two years of age when used for allergies.
Galactose-α-1,3-galactose, commonly known as alpha gal and the Galili antigen, is a carbohydrate found in most mammalian cell membranes. It is not found in catarrhines, including humans, who have lost the GGTA1 gene. Their immune systems recognize it as a foreign body and produce xenoreactive immunoglobulin M (IgM) antibodies, leading to organ rejection after transplantation.
Alpha-gal syndrome (AGS), also known as alpha-gal allergy or mammalian meat allergy (MMA), is a type of acquired allergy characterized by a delayed onset of symptoms after ingesting mammalian meat. The condition results from past exposure to certain tick bites and was first reported in 2002. Symptoms of the allergy vary greatly between individuals and include rash, hives, nausea or vomiting, difficulty breathing, drop in blood pressure, dizziness or faintness, diarrhea, severe stomach pain, and possible anaphylaxis.