is your specimen collection in low-resource regions outdated?
by Neoteryx | 2 min read
The typical way of collecting blood samples is, of course, venous puncture and filling a tube with blood. Although this method is well-established and reliable, it poses specific challenges in low-resource regions where barriers exist such as no electricity, no lab, and no clinical staff.
Challenges of Traditional Specimen Collection
Without an onsite lab, you must ship the samples to central lab, incurring shipping and handling costs in addition to risking the arrival condition of the sample. A sample that hasn't been properly temperature controlled or sealed and packaged might arrive in unusable condition.
Such failures waste not only resources but also the time you must then spend resampling and resending for analysis.
Another option is to adequately prepare a local lab for processing blood, which requires specialized equipment and additional trained staff to conduct the testing. Not to mention it can be quite costly and time-consuming to do so eroding much of the budget or grant dollars.
Dried Blood Sampling Success in Low-Resourced Areas
An ideal alternative to these costly and involved effects of using traditional blood sampling is to use dried blood spot cards and finger prick blood draws. This method is cost-effective because after the blood sample dries on the card and is packaged in an envelope, it doesn't require special conditions for transport.
Remote sampling can enable you to conduct onsite testing more easily and ensure that the samples are intact for additional later testing.
Using finger pricks and dried blood spot cards has resulted in increased diagnosis and management for those infected with HIV in low-resource regions. Similarly, dried blood spot cards have been shown to have equivalent detection limits for hepatitis C as testing plasma samples. One study based in remote hospitals in Malawi showed that viral load was detected more in dried blood spot samples than in plasma samples.
The results indicate that using dried blood samples instead of plasma samples could improve the monitoring of HIV therapy in low-resource regions by simplifying and decentralizing disease diagnosis and monitoring.
Researchers compared test results from both serum and dried blood spot cards for 50 pregnant participants in an Accra, Ghana public hospital. The researchers found a high correlation between the different sampling techniques confirming that dried blood spotting is a viable alternative to outdated, traditional wet specimen collection.
The New Dried Blood Spot
Volumetric absorptive microsampling (VAMS™) is the next-generation of dried blood sample technologies. This method eliminates the volumetric hematocrit effect typically seen with dried blood spot cards and produces reliable test results from a accurate 10 or 20 microliter volume. VAMS is especially suitable for studies that include populations with low blood volume or low blood flow because the absorbent tip ensures that the sample is homogenous with a very tiny sample amount.
Because collection with VAMS requires minimal training, non-clinical staff can collect specimens - in fact donors can collect their own specimen if necessary. Once collected, these specimens can be shipped through the post to a central lab and sample reformatting and extraction is automatable on liquid handling equipment commonly found in typical research laboratories.