Question:
Are Alpha-gal syndrome (AGS) cases on the increase in the U.S. and what about globally?
Answer:
Yes. Evidence strongly suggests that Alpha-gal syndrome (AGS) cases have increased substantially in the United States over the past 15 years, and reports are also rising globally.
In the U.S., the clearest data come from the Centers for Disease Control and Prevention. The CDC reported that more than 110,000 suspected AGS cases were identified between 2010 and 2022, and the agency estimates that as many as 450,000 Americans may actually have been affected because many cases go undiagnosed or unreported.
The CDC also states that suspected AGS cases have “increased substantially since 2010.”
A few reasons experts think U.S. cases are climbing:
Expansion of the Lone Star tick into new regions, including farther north and west.
Greater awareness and testing among physicians.
Climate and ecological changes that favor tick survival and spread.
Improved recognition of delayed allergic reactions after eating mammalian meat.
The syndrome is most common in the South, East, and Central U.S., where lone star ticks are established, but cases are increasingly being reported outside those traditional regions as well.
Globally, AGS is also considered an emerging condition, though the quality of surveillance varies widely by country. Cases have been documented in:
Australia
France
Germany
Spain
Sweden
Japan
South Korea
South Africa
and other parts of Europe, Asia, Africa, and North America.
Different tick species appear linked to AGS in different regions. For example:
In the U.S.: mainly the lone star tick.
In Australia: Paralysis tick.
In Europe: several Ixodes ticks species have been implicated.
Australia has reported especially notable growth. One recent report described roughly a 40% increase in cases since 2020. One important caveat: AGS is still underdiagnosed worldwide. Symptoms can appear hours after eating red meat, making the connection difficult to recognize. Many physicians are also unfamiliar with the condition.