It seems hard to believe that a disease spread by the "kissing bug" could be taken very seriously.

But although the condition is typically relatively mild and sometimes even has no symptoms, a new study finds that deaths caused by the disease often go undetected — and are much more common than previously thought.

Chagas disease — which is mostly found in Latin America but also occurs in southern Texas — is most commonly transmitted by so-called "kissing bugs," a subfamily of blood-sucking insects also known as assassin bugs that like to target the lip region (hence the name). The bugs carry a parasite called Trypanosoma cruzi, which is what causes Chagas disease. The parasite is transmitted via the bugs' feces: the insects defecate while they are feeding, allowing the parasite to move on to its new host.

The disease can also be transmitted via blood transfusion, organ transplant or from mother to child during pregnancy.

Once infected, Chagas disease (also known as American trypanosomiasis) can go undetected for years, or even decades, during which time it can cause damage to the heart, intestines and esophagus. Cardiomyopathy and arrhythmias caused by the damage can eventually prove fatal. In some cases, a Chagas-enlarged heart or intestines can actually explode.

According to the study, published in the journal PLOS, being infected with Chagas increases the risk of death between two and three times.

"In every age category, people who had Chagas died more than people who didn't have Chagas," head researcher Dr. Ligia Capuani, an infectious disease researcher at Faculdade de Medicina da Universidade de Sao Paulo, in Brazil, told CNN.

"So if you're infected early in life, you should be treated."

According to the World Health Organization, about 8 million people are living with Chagas disease, primarily in Latin America. It kills about 10,000 people each year.

The 'new HIV/AIDS of the Americas'

Several years ago, an editorial written by doctors for the journal PLoS Neglected Tropical Diseases likened Chagas to a health threat similar to the early years of the HIV/AIDS pandemic.

Lead author Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston, warns that the disease is spreading globally and there may be between 300,000 and 1 million cases in the U.S.

The doctors' comparison to the first two decades of the HIV/AIDS pandemic comes from several factors: both diseases disproportionately affect people living in poverty; the cost for treatment is incredibly high; both diseases are chronic conditions; and access to health care for people infected with Chagas remains low, as it was initially with HIV/AIDS.

"It's a forgotten disease among forgotten people," Hotez told The Star. "Can you imagine having 300,000 people in the suburbs with a serious case of heart disease caused by a bug? We wouldn't tolerate it as a society, but because it's happening to an indigenous people, we're silent."

Chagas is treatable, but only within the early stages of the disease. According to the Centers for Disease Control and Prevention (CDC), the early stage of Chagas occurs immediately after infection and may have mild or no symptoms at all. Symptoms during this stage can include fever, malaise, and a swelling of one eye. According to Doctors Without Borders, many countries with high levels of Chagas face shortages of benznidazole, the primary drug used to treat the disease.

The American Red Cross routinely screens blood donations for Chagas, but screening policies and requirements vary by location and organization. Texas does not require screening, nor are physicians in the state required to report instances of the disease, according to Wired.

Editor's note: This story has been updated since it was published in May 2012.