infectious disease – BioQuakes

Until recently, testing for COVID-19 has focused on the individual rather than on the environment. However, newly introduced technology promises to expand the scope of COVID-19 detection. Researchers at Washington University in St. Louis have developed an apparatus to detect the presence of the covert virus in environmental settings. Previous attempts at this technology have been limited by the volume of air tested. Without adequate air quantity, the sensitivity of the technology is negatively impacted. The current system, however, is capable of concentrating up to 1000 m³ of air per minute, compared to the two to eight cubic meters assessed in previous attempts. The result is a system that increases viral detection sensitivity while maintaining specificity.

The newly introduced apparatus functions by using centrifugal force to approximate viral particles to a liquid matrix adherent to the wall of the test chamber. Within the matrix are found nanobodies, bioengineered antibody fragments derived from llama antibodies. As we discussed in class, the human immune system is composed of humoral and self-mediated factors. Antibodies fall into the humoral category. While human antibodies consist of a light chain and a heavy chain, llama antibodies are composed of two heavy chains. By isolating heavy chain llama antibody fragments sensitized to the COVID-19 spike protein and then splicing multiple sensitized heavy chains together, researchers were able to amplify the viral signal, in a manner similar to PCR.

While the device has yet to be approved, cleared, or authorized by the FDA, it holds promise for meaningful real-world application. For example, prior to a large public event, indoor spaces could be screened for the presence of COVID-19. If the virus were detected, remediation could be performed and the environment retested prior to the public event. In doing so, countless potential COVID-19 infections could be avoided.

This novel technology diverges from current efforts at viral detection in that it does not rely on the existence of an infected individual but rather focuses on environmental detection thereby constituting primary prevention. In the future, the technology could be applied to prevention of other infectious diseases, both viral and bacterial. Further work is needed to explore the potential application of this method.

I urge readers to respond to the above and offer opinions.

While many may not know this, there are various types of pneumonia. The most common variant, CAP (community-acquired pneumonia), is the most prevalent strain of the infectious disease. As the name may suggest, CAP is acquired through daily interactions (whether that may be contact or inhalation of pathogens which could later travel to the lungs) with any surface that has bacteria such as Streptococcus pneumoniae and Haemophilus influenzae.

While pneumonia is a well-known infectious disease among the population in 2019 due to the plethora of literature and research done on it, most people do not know that other variants of pneumonia are contracted in different ways, through different strands of bacteria. HAP (hospital-acquired pneumonia or healthcare-associated pneumonia) can be contracted from extended periods of time in a hospital, nursing home, or rehabilitation center. This pneumonia variant is a result of the P. aeruginosa and Staphylococcus aureus bacteria, which are completely different from the bacteria that cause CAP.

HAP is most commonly contracted during extended hospital visits

The demographics of people who suffer from each of these variants appear to be mostly similar with the only difference being that CAP has a stronger association with COPD whereas HAP still has an association with COPD, but in a smaller portion of the demographic. Similarities between the two are the increased risk if one uses tobacco products or suffers from COPD, however, aside from these shared risk factors, the two variants are different in treatment methods (effectiveness of certain antibiotics) and contraction.

Relative to the microbiome, the major differences in the diseases can be found when testing biomarkers. According to Ann Transl and Thomas Tschernig of the “Annals of Translational Medicine”, “lower levels in HAP as compared to CAP were found for MMP-8 and soluble E-selection, higher levels in HAP as compared to CAP were found for protein C”.

The significance of this discovery lies in the fact that the different variants of pneumonia could not be prevented, diagnosed, or treated in the same ways, thus exemplifying the dangers that would arise if the different variants were not classified and identified.

Additional resources.

BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: infectious disease

From Individual to Environmental: COVID-19 Antigen Testing Expands

CAP v.s. HAP: Pneumonia in the Microbiome

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