The rapid spread of coronavirus disease 2019 (COVID-19) is an unprecedented global public health emergency. The proportion of the population who have had COVID-19 and who may therefore be immune to re-infection is currently unknown. Understanding more about this is important to help in managing the pandemic.
Therefore, we are running a large-scale surveillance study in the Fenland cohort to determine the proportion of people who have antibodies against COVID-19, an indication that a person has had the COVID-19 infection or vaccination. This is being done by repeated blood sample measures over a 6-month period to identify changes in infection during the study period.
Social distancing measures mean that taking blood in the normal way from someone’s arm is currently difficult, because this either means a healthcare practitioner would need to visit someone in their home or the participant would need to visit a clinical setting for the sample to be taken.
In the Fenland COVID-19 study, antibodies are being measured on dried blood spot samples taken by participants at home using a novel OneDraw device, and posted in to the MRC Epidemiology laboratories. The OneDraw device (Drawbridge Health) is enabling blood samples to be taken at home without the need for a healthcare practitioner. In addition, it is less invasive, takes a small amount of blood, and is less painful than standard finger-prick test or venesection.
In this COVID-19 capillary and venous blood antibody testing (CAVA) study, we sought to to determine if dried blood spots, collected either by a finger prick blood test or the OneDraw device, provide the same antibody test result for COVID-19 as blood taken from a vein in the arm.