Team:Calgary/Project/BsDetector/TargetDiseases

From 2014.igem.org

Revision as of 01:57, 16 October 2014 by Dae.kim (Talk | contribs)

Target Diseases

A trend of misdiagnosis

Febrile illnesses which pose symptoms similar to malaria are of particular concern in malaria-endemic countries. In Patients who present symptoms such as fever, nausea, and headache are often suspected to have malaria before a diagnosis is even made due to malaria's high prevalence in these regions. The tragedy lies in the fact that patients who test negative for malaria are often given antimalarial drugs and considered to have malaria despite their diagnosis. The over-prescription of antimalarials fosters an environment for drug resistance, unnecessarily taxes healthcare systems, and most importantly, worsens the patient's condition. Clinicians in malaria-endemic countries are presented with a dilemma when a patient with symptoms similar to malaria is discovered to actually not have the disease through commonly used diagnostics such as the Rapid Diagnostic Test (RDT) and microscopic blood smears. On one hand, they know that their patient most likely does not have malaria based on the tests, but on the other, they do not have the diagnostic means to explore the possibility of other diseases and know missing a case of malaria is considered unforgivable. Physicians must make an important decision at this junction based on limited information, the consequences of which could have severe effects on the patient. Some clinicians will opt to treat all cases of fever, nausea, and headache, as malaria and indiscriminately prescribe anti-malarial drugs, consequently ensuring that no case of malaria goes unaddressed. The ramifications of such practice can be tremendous, as we have seen in Sudan. Others must ask themselves the question, "if it's not malaria, then what is it?". Unfortunately, physicians who fear the consequences of over-prescription and wish to consider alternative diagnoses are left with very few diagnostic options due to limited time and resources.

We at iGEM Calgary believe we have the makings of a solution to this problem. We propose a rapid diagnostic test capable of diagnosing several diseases in parallel, thus opening the door to more routes of treatment and allowing the physician to make a more informed decision. Additionally, in cases of a patient being co-infected with both malaria and different febrile illnesses - a common occurence in malaria-endemic countries - our device will facilitate the diagnosis of all diseases instead of just one. Current malaria diagnostic methods do not offer this feature, which may lead to dangerous situations. For example, if a co-infected patient is given a RDT and tests positive, the physician may make the assumption that the patient only has malaria and remain oblivious to other illnesses. Nonetheless, we must state that our device was not designed to compete with existing, reputable diagnostics pertaining to certain diseases. Rather, our objective was to offer a comprehensive and affordable diagnostic option that tests for as many diseases as possible at the lowest cost possible. We researched a wide spectrum of infectious diseases symptomatically similar to malaria and common throughout the world, and decided to target the following diseases:

  • Typhoid fever
  • Dengue fever
  • Meningitis
  • Pneumonia
  • Visceral leishmaniasis

This is not to say, however, that our device is limited specifically to these diseases. Our device was designed with modularity and customization in mind. By simply switching a few DNA sequences within our genetically engineered B. subtilis our device has the potential to detect virtually any pathogen whose genome has been sequenced and made available in public repositories. Based on which diseases are common in certain parts of the world, we can modify our device to detect those diseases of interest before shipping it to the end-user. The true strength of our device lies in its ability to adapt to when necessary. Think of our device as the utility knife of diagnostics, affordable and ready for any situation.