MAY 24, 2017 03:07 PM PDT

Chagas Disease More Deadly Than Thought

WRITTEN BY: Carmen Leitch
1 18 956

Chagas disease is a parasitic disease transmitted by insects and has been classified as one of the most important neglected diseases by the World Health Organization. It is known to affect millions of people in Central and South America and some in the US, thought to have been infected in their home countries. It typically sickens people for a few months, and then symptoms fade. It had been thought that the disease ended there; new evidence shows that it can seriously increase a person’s risk of death. The new study in PLOS Neglected Tropical Diseases also reported the likelihood that deaths due to Chagas disease have been under-reported. 

Chagas disease is caused by what’s commonly called a kissing bug, Trypanosoma cruzi. When an infected bug bites a person, it can sicken them with fever, headaches and swelling. The symptoms usually go away and infected people live a normal life for decades without any indication of the illness. However, it was eventually learned that the cardiac, digestive and neurological symptoms of Chagas come back. 

For this new study, a team of researchers led by Ligia Capuani, at the University of Sao Paulo, Brazil, analyzed a repository of blood samples that included 2,842 Chagas-positive and 5,684 Chagas-negative specimens taken from blood donors in Sao Paulo from 1996 to 2000. Because of the routine screening of blood donors there for Chagas disease, blood samples that were positive for the disease were assumed to be taken from people in the intermediate, or symptom-free, stage of the disease. The researchers also had access to death records in Brazil, enabling to them learn the time and manner of death of any donors that had died.

It was found that of the Chagas-positive donors, 159 (5.6%) died at some point over the course of the study, however only 103 (1.8%) of those testing negative for the disease had died. That indicated the overall death risk had more than doubled. The scientists also knew they had to account for other causes of death; when the analysis was restricted to death due to cardiac abnormality or was otherwise Chagas-related, the difference was even more pronounced. People impacted by the disease were then found to have a 17.9 greater risk of death. Interestingly, Chagas was not often noted as a cause of death for many of those that had shown signs of heart disease and had been infected with Chagas.

It’s likely that doctors are not making the important connection. "The fact that Chagas disease was not reported as an underlying or associated cause of death on the death certificate of 42% of seropositive donors that died due to cardiac causes demonstrates under ascertainment of Chagas disease pathogenesis, highlighting its status as a neglected tropical disease," the researchers say. "Research is urgently needed in order to test new therapeutic options with fewer side effects and to find better correlates of disease progression."

 

In the United States, there is some concern that doctors are not even aware of the disease in its early stages, and are not making the diagnosis at all. The video above discusses that issue.

 

Sources: AAAS/Eurekalert! via PLOS, PLOS Neglected Diseases, CDC, WHO

About the Author
  • Experienced research scientist and technical expert with authorships on 28 peer-reviewed publications, traveler to over 60 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
MAY 09, 2018
Microbiology
MAY 09, 2018
A Giant Ocean Virus has Been Isolated & Characterized
One study estimated that we share the planet with at least 320,000 microorganisms have the potential to infect mammals.
JUN 28, 2018
Videos
JUN 28, 2018
A Vaccine for Syphilis is in the Works
Now that the scientists have studied the protein and its potential, they will begin to enroll participants in a study.
JUL 04, 2018
Drug Discovery
JUL 04, 2018
Discovery of New Properties of an Anti-Tuberculosis Drug
  Investigators at the University of Otago found novel properties of a new anti-tuberculosis drug which may inspire more new drugs to treat tuberculos
JUL 04, 2018
Videos
JUL 04, 2018
How Did Viruses Originate?
There is still a debate about whether or not viruses are a form of life, and we really don't know where they came from.
AUG 13, 2018
Microbiology
AUG 13, 2018
Insight Into the Origins of Junk DNA - From Koalas
The human genome isn't only genes. There's also long, repetitive sequences with an unknown function and origin.
AUG 13, 2018
Genetics & Genomics
AUG 13, 2018
A Kind of Forensics to ID the Source of Bacterial Outbreaks
Scientists at Mayo Clinic have developed a way to use whole genome sequencing to locate the source of deadly bacterial pathogens.
Loading Comments...