viral infection and immunity: the promise of remote sampling
We are living in unprecedented times. On the 11th of March 2020, the world health organization upgraded the COVID-19 epidemic as a pandemic and different countries have implemented different ways to tackle the spread of this disease. Much of this involves social distancing especially for the vulnerable in our societies.
The rapid spread of the virus is and is looking to put strains on healthcare systems and the WHO has recommend governments test for the virus as much as they can.
Current Ways to Test for Viral Infection
There are two primary ways to specifically test for viral infection:
- Testing for for the direct presence of the virus
- Testing for antibodies raised against the virus.
Direct Viral Testing
Direct viral testing, such as what is currently being employed for diagnosis of COVID-19, involves detecting the presence of viral nucleic acids in affected tissues using rapid PCR techniques. Although rapid PCR allows for detection of specified viruses, it says nothing about if an individual has raised any antibodies to the virus.
Detecting for raised antibodies, allows for vaccine manufacturers to test the efficacy of their vaccines. This involves employing the use immunoassays specific to the pathogen or pathogens of choice and involves a blood test. However, this is challenging to accomplish when social distancing measures have been employed and healthcare systems are being stretched. In short, development of home testing kits where patients can post a dried blood sample to a laboratory would potentially help to reduce such a burden.
Use of Remote Dried Blood Assays in Diagnosis and Monitoring of Disease
The use of remote sampling of dried blood samples for diagnosis of disease is widely used in screening neonates for inborn errors of metabolism. Moreover, over the years, there have been many publications on the use of remote dried blood collection for the diagnose and monitoring of viral infections such as HIV and hepatitis.
In 2019, a paper was published in the Journal of Clinical and Translational Science, where the use of remote Volumetric Absorptive Microsampling was evaluated to successfully measure immunity to 33 stains of influenza virus. The test employed, was a multidimensional multiplex immunoassay to measure IgG antibodies. 21 healthy volunteers were used to evaluate the feasibility of combining the benefits of at-home patient centric sampling, with the mPlex-Flu assay. In each case, phlebotomists were used, to collect both venous blood, in the traditional way, and capillary blood using Mitra samples. The volunteers were then also asked to self-collect blood at home using Mitra VAMS samplers and mail the samplers back to the lab. The results were very impressive
- Very good concordance (R2 0.9470) was observed, when comparing the venous serum samples vs. extracts from the dried Mitra samples collected by the phlebotomists
- Equally, excellent concordance (R2 0.9496) was observed between Mitra samples, collected by the phlebotomists and those self-collected by volunteers at home
- The samples also looked very stable - what is even more encouraging is that this study, was conducted in the New York area, during the heat of August where the samples mailed back to the lab would have been exposed to high temperatures
Can This Approach Be Used for COVID-19?
We contacted the lead author on the study (Dr. Jiong Wang) to see if they were developing a similar assay for COVID-19. She said to us, "We are going to be using the same methods to estimate the antibodies against COVID-19 viral proteins, such as S, N, M, E and multiple strains. That will be helpful for vaccine development and understanding the mechanism of COVID-19 severe illness. We intend to use the Neoteryx kits for large scale sampling."
If you want to know more about the groundbreaking work from the Rochester Medical Centre please click below. Furthermore, if you are curious to explore how volumetric dried blood assays can help to obtain remote blood samples please contact us to talk with one of our expert Microsampling Specialists or visit our website.