Officials warn of tick-borne meat allergy

Alpha-gal syndrome often caused by tick species with a growing range

Tickborne illnesses are on the rise across the nation, and while Lyme disease is the most common severe infection, a peculiar tick-caused illness that leads to an allergy to red meat has entered the spotlight.

The Centers for Disease Control and Prevention recently rang the alarm about the emerging concern posed by what’s known as alpha-gal syndrome. Between 2010 and 2022, there were more than 110,000 suspected cases of the tick-borne condition identified, but the CDC estimates the true number of cases may be as high as 450,000.

Cases of alpha-gal have occurred primarily in the southeastern United States, which is the traditional crawling grounds of the lone star tick, the species associated with the syndrome in the United States. But the range of the lone star tick and of alpha-gal has been growing. There have even been a very small number of cases confirmed among people who live in the Lehigh Valley.

People who suffer from alpha-gal syndrome may experience a wide range of symptoms after eating certain animal products, including hives, itchy rash, nausea, vomiting, heartburn, indigestion, diarrhea, cough, shortness of breath, difficulty breathing, drop in blood pressure, swelling, dizziness, faintness or severe stomach pain.

Dr. Jeffry Jahre, senior vice president of medical and academic affairs and chief emeritus of infectious diseases for St. Luke’s University Health Network, said the network had its first confirmed patient several years ago. He said the network tests for alpha-gal about once per week.

Dr. Robert Zemple, chief of Lehigh Valley Health Network’s allergy division, said LVHN has one patient he knows of with the condition and they will periodically test for it.

Jahre said knowing the actual prevalence of the condition is currently impossible. Alpha-gal is not a reportable illness and many people don’t know to get tested for it.

“One of the vexing things is, [the allergic reaction] may not happen each time that you eat, it’s very nonspecific. Sometimes it’s misdiagnosed as irritable bowel syndrome or some type of intolerance when it is actually a true allergy,” Jahre said.

What kind of ticks do you find in the Lehigh Valley?

Ticks and tickborne illness are always a concern in the Lehigh Valley, where certain ticks thrive in abundance. But in the last 20 years tick populations and tickborne diseases have become an increasing problem all across the country.

Marten Edwards, chair of biology for Muhlenberg College, said that about 25 species of ticks have been found in Pennsylvania, though most are not found in large populations in the Lehigh Valley, and of those, only a handful interact with humans. The deer tick, or eastern blacklegged tick, is the most common in forested areas here. It is infamous as the top spreader of diseases like Lyme, babesiosis and anaplasmosis.

Another common species is the American dog tick, which prefers grassy areas. In Pennsylvania, American dog ticks rarely transmit serious diseases but they are relatively large and more than willing to feed on humans.

And there are a few ticks we can expect will make homes for themselves in the Valley soon enough. One is the longhorned tick, which was accidentally introduced to New Jersey from New Zealand a little more than a decade ago. While it isn’t yet known to be a disease vector for humans in the United States, it can be especially harmful to livestock and deer.

Another is the lone star tick, which may have lived here in the past, but is set to make a comeback.

“It is not very common in this area of Pennsylvania,” Edwards said. “Some specimens have been found, but I have spent literally hundreds of hours looking for ticks in the most tick-infested woods I could find, and I haven’t found any of these ticks yet. But other people have found a few, so I expect they will be common in time.”

Notably, the lone star tick is the one associated with alpha-gal syndrome in the U.S.

Edwards said that when a tick feeds on blood, it releases saliva into its host to prevent blood clotting and suppress the immune system’s response against the tick, among other things. The saliva of the lone star tick contains a particular type of sugar, which is also found in red meat, milk, and other products of non-primate mammals.

Zemple said the body may then produce antibodies that recognize this sugar as invasive, which will then cause allergic reactions. Alpha-gal syndrome may take multiple exposures to the lone star tick before it develops.

And strangely, the allergic reactions alpha-gal syndrome sufferers experience don’t usually occur until about 2-6 hours after eating.

Zemple said allergists can test for alpha-gal syndrome by doing blood work. And like most allergies, a plan can be put in place for severe reactions such as having epinephrine at the ready.

However, there is no known cure for alpha-gal syndrome. The condition may be temporary for some, but it can be permanent for others.

Jahre said the best treatment for any tick-borne illness is to avoid being bitten by ticks in the first place.

One step to deter ticks is wearing the right clothing when spending time outside — long sleeve shirts, long pants and socks, preferably with your plants tucked into socks. Another is by treating clothes with products containing 0.5% permethrin and using Environmental Protection Agency-approved tick repellents.

It is also smart to avoid areas where ticks tend to live and “quest,” such as wooded and brushy areas with high grass and leaf litter. When hiking the CDC recommends walking in the center of trails.

And after spending time outdoors, the CDC recommends checking all over the body for ticks, especially in these areas:

„ Under the arms

„ In and around the ears

„ Inside the belly button

„ Back of the knees

„ In and around hair

„ Between the legs

„ Around the waist