Chagas disease, caused by the parasite Trypanosoma cruzi, is an insidious illness that has quietly found its way into California and 29 other states in the U.S.
Although it kills more people in Latin America than malaria each year, many remain unaware of its presence in their communities, with researchers estimating that roughly 300,000 individuals in the U.S. may be infected without knowing it.
The disease is primarily transmitted through the bites of kissing bugs, blood-sucking insects that harbor the parasite.
In California alone, four species of these bugs are known carriers of Trypanosoma cruzi, with research indicating that as many as one-third of kissing bugs in areas like Griffith Park are infected.
A team of medical professionals and public health experts is urging the World Health Organization and the Centers for Disease Control and Prevention to classify Chagas as endemic in the U.S.
Their goal is to promote awareness, education, and sufficient public health investments in a disease often stigmatized as affecting only poor, rural migrants from tropical regions.
As Norman Beatty, a medical epidemiologist at the University of Florida, noted, Chagas has long impacted Latin American populations but is now increasingly recognized as a domestic issue.
Notably, Salvadore Hernandez, a Northern California cardiologist, shared a case of a child from the Hollywood Hills who contracted the disease without traveling abroad, suggesting that local transmission is possible in affluent neighborhoods where kissing bugs are prevalent.
In addition to humans, the parasite has been found in various local wildlife, including wood rats, skunks, and even species such as bats and raccoons.
Researchers like Sarah Hamer, an epidemiologist at Texas A&M University, emphasized that kissing bugs have a broad feeding range, leading to a diverse reservoir for T. cruzi in wildlife populations.
California is home to the largest concentration of Chagas cases in the U.S., with between 70,000 and 100,000 people currently infected.
The presence of significant immigrant populations from endemic countries contributes to these statistics.
However, the local transmission of the parasite cannot be ruled out either.
A small study conducted by the California Department of Public Health found that a significant portion of reported cases between 2013 and 2023 had been acquired internationally, yet local transmission remains a possibility.
Currently, Chagas disease is not considered a reportable disease statewide in California, meaning that there is no obligatory requirement for physicians and health systems to report on it as there is with other diseases like influenza or Lyme disease.
Nevertheless, Los Angeles County has implemented mandatory reporting, where health officials confirmed approximately 18 cases between 2019 and 2023, with the acknowledgment that undiagnosed cases likely exist.
Gabriel Hamer, an entomologist at Texas A&M, highlighted that the confirmed human cases in the U.S. represent only a small fraction of the actual number, indicating a dire need for standardized reporting and active surveillance.
Many individuals, like Janeice Smith, a retired teacher from Florida, only discover their Chagas status when prompted by blood donation centers.
Smith became aware of her condition in 2022 after receiving notification from a donation center, revealing that she likely contracted the disease during a family trip to Mexico in 1966.
After suffering severe symptoms like high fever and swollen eyes during that trip, her diagnosis remained elusive for decades until recent testing.
Hamer pointed out that the immediate effects of kissing bug bites can range from swollen limbs to anaphylaxis, but it is the chronic effects of Chagas disease that can have life-threatening consequences.
The symptoms often mimic other forms of cardiac issues, leading many patients to visit doctors without ever being screened for Chagas.
According to Hernandez, many patients are diagnosed too late, which can lead to severe repercussions such as organ transplantation or costly medical interventions.
Anti-parasitic medications are available to halt disease progression, but many are not diagnosed in time to benefit from them.
In addition to humans, Chagas is also a concern in veterinary medicine, especially regarding dogs that show similar signs, such as heart failure or arrhythmias.
Ashley Saunders, a veterinary cardiologist at Texas A&M, noted that younger dogs are often severely affected, while older dogs might enter heart failure after a prolonged infection.
Dogs typically contract the disease by ingesting kissing bugs, which provide a more concentrated dose of the parasite than through bites.
The growing awareness of Chagas disease highlights the need for increased understanding, better screening practices, and more robust public health initiatives to combat this neglected disease within the U.S.
Given its stark underdiagnosis and the potential for severe health consequences, experts believe that proactive measures are essential to mitigate the ongoing threat posed by Chagas disease.
image source from：latimes
