Bad news, burger fans: one tick bite has the potential to permanently remove red meat from your menu.
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A meat allergy known as alpha-gal syndrome (AGS) appears to be triggered by a tick bite, say the researchers. The number of cases is also increasing. There were only 24 cases reported in the United States in 2009. In 2018, the number exceeded 34,000.
So what do we know about this emerging allergy threatening to chill the coals on a favorite backyard grill option? And what can you do to avoid it? Allergist Arnaldo Perez, MDgives food for thought.
What is alpha-gal syndrome?
SGA is a severe allergy to a sugar molecule called galactose-alpha-1,3-galactose (commonly known as alpha-gal), which is found in the cells of most mammals. Symptoms appear after eating meat or other animal-related food products, such as dairy products or gelatin.
The syndrome and its link to ticks was discovered by researchers in 2009. AGS has been increasingly studied over the years to better understand it.
“Tick bites are an unusual way to become allergic to a substance,” says Dr. Perez. “It’s a recent association, that’s for sure. It’s still quite rare, but it’s something to be aware of, especially if you have unexplained allergic reactions.
What tick causes red meat allergy?
A small bugger – the lone star tick – appears to be the main source of AGS in the United States. The tick has long made its home in the southeastern states, but its range has now expanded into the Midwest and Northeast.
The lone star tick is very aggressive, according to Centers for Disease Control and Prevention (CDC). It is most active (and biting) from early spring to late fall.
The name comes from the appearance of the adult female, which has a single white dot – or “lone star” – on her back. Besides AGS, its bite can lead to Lyme diseaseHeartland virus, Bourbon virus, and Southern tick-associated rash (STARI).
However, other tick species have not been ruled out as potential sources of SFA. “There are other parts of the world where this phenomenon has been identified, and the lone star tick is not there,” notes Dr. Perez.
Like most food allergy, reactions can range from mild to life-threatening. Signs of an AGS reaction include:
- Skin rashes or urticariawhich are present in the vast majority of AGS reactions.
- Gastrointestinal problems such as stomach painssevere stomach pain or diarrhea.
- Difficulty breathing.
- Swelling of the lips, throat or tongue.
What is unusual about AGS reactions, however, is the length of time it takes for symptoms to appear. Most AGS reactions occur three to six hours after exposure. (For comparison, most food allergic reactions occur within minutes.)
“This delay can make it more difficult to directly associate with what was eaten,” says Dr. Perez.
Test for AGS
Talk to your health care provider if you have signs of AGS. Confirmation of the syndrome usually goes through a blood test that looks for antibodies against alpha galactose. A skin test may also be performed.
Foods and products to avoid if you have AGS
The prohibited list begins with meat from mammals. This includes beef, pork, lamb, and venison, as well as meat from furry and warm-blooded creatures. “All of these can cause a reaction,” Dr. Perez points out.
The good news? Poultry and fish do not contain alpha-gal and can remain in your diet.
A person with SGA may also need to avoid:
- Lard (melted pork fat).
- Gelatin, which is made from boiling animal bones, skin and tissues.
Countless medications, personal health items, and household products may also contain alpha-gal. It’s best to discuss the details with your allergist or healthcare provider to determine your risk.
Treatment of AGS reactions
Some people with SGA will be prescribed an epinephrine auto-injector — more commonly known as the EpiPen® — for potential use in the event of an anaphylactic reaction, Dr. Perez says.
Over-the-counter antihistamines can be used to help relieve symptoms of less severe reactions.
There is no current cure for AGS.
How to prevent AGS
Since tick bites are the primary cause of AGS, taking the proper precautions outdoors is your best defense against the syndrome, says Dr. Perez. He recommends :
- Wear clothes that completely cover your skin in areas of tick activity. This means long-sleeved shirts, pants, and knee-high socks. Tuck your pant legs into your socks can provide additional protection.
- Use bug sprays on your clothes and skin to ward off creepy crawlies. DEET-based repellents are safe to use.
Also, be sure to check your clothes and skin for ticks before coming back inside. Remove attached ticks with tweezers as soon as possible. (Review CDC guidelines when removing ticks.)