Assessment of dried blood samples as an alternative less invasive method for detection of Hepatitis E virus marker in an outbreak setting

Abstract

Hepatitis E virus (HEV) is the causative agent of hepatitis E. It can be asymptomatic, associated with acute self-limiting hepatitis or acute liver failure. The conventional diagnosis of HEV infection relies on anti-HEV IgM serology. The collection of blood samples by venepunture for laboratory confirmation is often difficult during an outbreak. Thus, testing the specimens of dried blood spots (DBS) on filter papers can prove to be a feasible alternative. The present study aimed to evaluate the applicability of anti-HEV IgM detection from DBS samples and the stability of anti-HEV IgM detection at varied time interval, at various storage temperatures. Paired blood and DBS sample were collected from 44 jaundiced patients and eight healthy controls during HEV outbreaks. The DBS were tested for anti-HEV IgM by available ELISA kit with in-house modifications. Three cut offs were determined, that is, the CO1: kit cut-off, CO2: mean of negative controls above 3SD and CO3: area under Receiver operating Curve. The sensitivity of anti-HEV IgM detection ranged from 86-91%. The maximum sensitivity (91%) and specificity (100%) was obtained using CO3. Maximum stability of anti-HEV IgM antibodies (100%) was observed till 65 days at 4°C. Storage at 37°C significantly reduced anti-HEV IgM positivity, wherein 42.85% sample became negative by 45 days. DBS showed good sensitivity and specificity for detecting anti-HEV IgM and can be considered an alternate to serum sample. Moreover, anti-HEV IgM was stable at 4°C, which makes DBS a preferred method for storage and transportation of the sample to reference laboratory.

Reliability of dried blood spot (DBS) cards in antibody measurement: A systematic review

“…were stable until the 7 th day [2]. Nine studies [2,19,24,26,38,46,[55][56][57] demonstrated minimal variations in antibody concentrations compared to baseline cards stored at -20˚C, over 21 to 200 days.…”

“…Six studies [2,19,21,33,54] concluded that antibody levels in DBS were stable at room temperature, ranging from 7 days to 28 days. A slight decline was observed in antibody concentrations in DBS samples that were stored at 2-8˚C, although five studies [2,24,44,53,56] demonstrated that DBS samples were stable for up to 210 days at this temperature (range of storage time: 7 to 210 days). Five studies [24,36,53,55,56] found that antibodies in DBS samples stored at 37˚C were unstable with antibody concentrations steadily declining in as few as three days [53].…”

Use of Filter Paper to Measure Alcohol Biomarkers among Opioid-Dependent Patients on Agonist Maintenance Treatment: A Community-Based Study

“…Previous studies from our group and other authors also reported filter paper as a reliable matrix for biochemical measurements. [1314151617]…”

Dried Blood Spots for Measuring Vibrio cholerae-specific Immune Responses

“…More recently, DBS have been used for screening of metabolic disorders, detection of pathogens, and drug testing, in various sample types including blood, saliva, breast milk and stool [ 4 – 6 ]. Several studies have demonstrated the utility of DBS for serological and molecular detection of a number of infectious diseases, including tetanus [ 7 ], diphtheria [ 8 ], HIV [ 9 – 11 ], hepatitis A, B, C and E [ 12 – 15 ], dengue [ 16 , 17 ], polio [ 18 ] and measles [ 19 ]. The performance characteristics of DBS tests have approached that of serum assays, and their low costs and convenience have resulted in widespread use and endorsement by the WHO [ 20 ].…”