News Release

Novel method for storing and transporting cerebrospinal fluid samples for diagnosis of JEV

Peer-Reviewed Publication


In resource poor areas patient samples often have to travel long distances for suitable diagnosis. Filter paper is currently used for the storage and transport of dried blood samples, however there is very little research on similarly simple and inexpensive methods for the transport of other diagnostic fluids. This prompted researchers from the Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU) to explore an appropriate storage system of cerebrospinal fluid. Published in PLOS Neglected Tropical Diseases, they propose the use of pre-cut filter paper to store samples for detection of anti-Japanese encephalitis virus antibodies from patient cerebrospinal fluid.

While novel and complex diagnostic tests are developing at a rapid rate they are not always accompanied by a corresponding development in laboratory infrastructure. Japanese encephalitis virus is one of the most common causative pathogens in Asia. However, diagnosis relies on laboratory facilities to test for antibodies in cerebrospinal fluid. The researchers tested different techniques and filter papers to find the optimal method for transporting dried cerebrospinal fluid samples without the need for keeping samples frozen.

The researchers investigated a novel technique using a pre-cut circle of cellulose-cotton paper. This circle was saturated with the maximal fluid volume that could be added before being dried. To test whether Japanese encephalitis virus could be successfully identified from the samples, the researchers carried out a retrospective analysis on cerebrospinal fluid for patients tested for the virus between 2009 - 2015 in Laos, with a total of 132 samples containing sufficient fluid volume for testing.

Samples were dried on the pre-cut filter paper and then left for 30 days at room temperature. When tested for the presence of viral antibodies 34 dried samples and 38 neat samples tested positive, with overall agreement of 92.4% (86.5 - 96.3 95% CI). Compared with neat (i.e non-dried) samples the dried spots showed 81.6% positive agreement (65.7 - 92.3 95% CI) and 96.8% negative agreement (91.0 - 99.3 95% CI).

"This novel method for saturating dried cerebrospinal fluid spots has the potential to enhance our knowledge of Japanese encephalitis virus epidemiology, and inform health policies where they are most needed," explains Dr. Tehmina Bharucha from LOMWRU and the London School of Hygiene and Tropical Medicine. "It could also be transferred for use in diagnosing other infectious diseases, including using other body fluid samples."

In Laos, laboratory diagnosis of Japanese encephalitis virus is only available in the capital city of Vientiane. A simple tool for storage and transport of samples will greatly improve clinical diagnosis, as well as proving a vital tool for the study of epidemiology and etiology of the infection.


Please contact if you would like more information about our content and specific topics of interest.

All works published in PLOS Neglected Tropical Diseases are open access, which means that everything is immediately and freely available. Use this URL in your coverage to provide readers access to the paper upon publication: (Link goes live upon article publication)

Contact: Tehmina Bharucha,, 00447969080397

Funding: This study was supported by the Wellcome Trust of Great Britain. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

About PLOS Neglected Tropical Diseases

PLOS Neglected Tropical Diseases is a peer-reviewed, open-access journal devoted to the pathology, epidemiology, prevention, treatment, and control of the neglected tropical diseases, as well as public policy relevant to this group of diseases. Please contact if you would like more information about our content and specific topics of interest.

Media and Copyright Information

For information about PLOS Neglected Tropical Diseases relevant to journalists, bloggers and press officers, including details of our press release process and embargo policy, visit .

PLOS Journals publish under a Creative Commons Attribution License, which permits free reuse of all materials published with the article, so long as the work is cited.

About the Public Library of Science

The Public Library of Science (PLOS) PLOS is a nonprofit publisher and advocacy organization founded to accelerate progress in science and medicine by leading a transformation in research communication. For more information, visit


This press release refers to upcoming articles in PLOS Neglected Tropical Diseases. The releases have been provided by the article authors and/or journal staff. Any opinions expressed in these are the personal views of the contributors, and do not necessarily represent the views or policies of PLOS. PLOS expressly disclaims any and all warranties and liability in connection with the information found in the release and article and your use of such information.

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.