Dry Blood Spots a Reliable Method for Measurement of Hepatitis B Viral Load in Resource-Limited Settings.
OBJECTIVE
Hepatitis B virus (HBV) quantification is essential in the management of chronic hepatitis B, both to determine treatment eligibility and in the monitoring of treatment effect. This test, however, is rarely available in resource-limited settings due to high costs and stringent requirements for shipment and storage of plasma. Dried Blood Spots (DBS) can be a convenient alternative to plasma, but its use for HBV monitoring has not been investigated under real-life conditions in Africa.


METHODS
The performance of DBS in HBV quantification was investigated using a modified commercial test (Abbott RealTime HBV assay). Paired DBS and plasma samples were collected from an HBV positive cohort in Addis Ababa, Ethiopia. DBS were stored at ambient temperature for 4-39 days before shipment to the laboratory.


RESULTS
Twenty-six paired samples were selected covering the total range of quantification, from 2.14 log IU/ml to >7 log IU/ml. HBV was detected in 21 of 21 (100%) DBS from patients with a corresponding plasma viral load above 2.70 log IU/ml. The mean difference between plasma and DBS was 0.59 log IU/ml, and the correlation was strong (R2 = 0.92). In stability studies there was no significant change in DBS viral load after storage at room temperature for up to 12 weeks.


CONCLUSIONS
This study suggests that DBS can be a feasible and reliable alternative to plasma for quantification of HBV in resource-limited settings. DBS can expand access to antiviral treatment for patients in low- and middle-income countries.
Department of Virology, Norwegian Institute of Public Health, Oslo, Norway.
Kathrine
K
Stene-Johansen
Department of Virology, Norwegian Institute of Public Health, Oslo, Norway.
Nadeem
N
Yaqoob
Department of Virology, Norwegian Institute of Public Health, Oslo, Norway.
Joakim
J
Overbo
Medical Department, St. Paul's Hospital Millennium Medical College, Addis Ababa, Ethiopia.
Hanna
H
Aberra
Medical Department, St. Paul's Hospital Millennium Medical College, Addis Ababa, Ethiopia.
Hailemichael
H
Desalegn
Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia.|Centre for Imported and Tropical Diseases, Oslo University Hospital, Ullevål, Oslo, Norway.
Nega
N
Berhe
Centre for Imported and Tropical Diseases, Oslo University Hospital, Ullevål, Oslo, Norway.|Department of Microbiology, Vestre Viken HF, Bærum, Norway.
Asgeir
A
Johannessen
D000349:Africa; D001769:Blood / Q000821:virology*; D001800:Blood Specimen Collection / Q000379:methods*; D003890:Desiccation / Q000379:methods; D006295:Health Resources; D006509:Hepatitis B / Q000097:blood / Q000821:virology; D006515:Hepatitis B virus / Q000302:isolation & purification*; D006801:Humans; D010949:Plasma / Q000821:virology; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D019562:Viral Load / Q000379:methods*