@article{fdi:010066776,
  title = {{P}re-cut filter paper for detecting anti-{J}apanese encephalitis virus {I}g{M} from dried cerebrospinal fluid spots},
  author = {{B}harucha, {T}. and {C}hanthongthip, {A}. and {P}huangpanom, {S}. and {P}honemixay, {O}. and {S}engvilaipaseuth, {O}. and {V}ongsouvath, {M}. and {L}ee, {S}. and {N}ewton, {P}. {N}. and {D}ubot {P}{\'e}r{\`e}s, {A}udrey},
  editor = {},
  language = {{ENG}},
  abstract = {{B}ackground {T}he use of filter paper as a simple, inexpensive tool for storage and transportation of blood, '{D}ried {B}lood {S}pots' or {G}uthrie cards, for diagnostic assays is well-established. {I}n contrast, there are a paucity of diagnostic evaluations of dried cerebrospinal fluid ({CSF}) spots. {T}hese have potential applications in low-resource settings, such as {L}aos, where laboratory facilities for central nervous system ({CNS}) diagnostics are only available in {V}ientiane. {I}n {L}aos, a major cause of {CNS} infection is {J}apanese encephalitis virus ({JEV}). {W}e aimed to develop a dried {CSF} spot protocol and to evaluate its diagnostic performance using the {W}orld {H}ealth {O}rganisation recommended anti-{JEV} {I}g{M} antibody capture enzyme-linked immunosorbent assay ({JEV} {MAC}-{ELISA}). {M}ethodology and {P}rincipal {F}indings {S}ample volumes, spotting techniques and filter paper type were evaluated using a {CSF}-substitute of anti-{JEV} {I}g{M} positive serum diluted in {P}hosphate {B}uffer {S}olution ({PBS}) to end-limits of detection by {JEV} {MAC}-{ELISA}. {A} conventional protocol, involving eluting one paper punch in 200 mu l {PBS}, did not detect the end-dilution, nor did multiple punches utilising diverse spotting techniques. {H}owever, pre-cut filter paper enabled saturation with five times the volume of {CSF}-substitute, sufficiently improving sensitivity to detect the end-dilution. {T}he diagnostic accuracy of this optimised protocol was compared with routine, neat {CSF} in a pilot, retrospective study of {JEV} {MAC}-{ELISA} on consecutive {CSF} samples, collected 2009-15, from three {L}ao hospitals. {I}n comparison to neat {CSF}, 132 {CSF} samples stored as dried {CSF} spots for one month at 25-30 degrees {C} showed 81.6%(65.7-92.3 95%{CI}) positive agreement, 96.8% (91.0-99.3 95% {CI}) negative agreement, with a kappa coefficient of 0.81 (0.70-0.92 95% {CI}). {C}onclusions/{S}ignificance {T}he novel design of pre-cut filter paper saturated with {CSF} could provide a useful tool for {JEV} diagnostics in settings with limited laboratory access. {I}t has the potential to improve national {JEV} surveillance and inform vaccination policies. {T}he saturation of filter paper has potential use in the wider context of pathogen detection, including dried spots for detecting other analytes in {CSF}, and other body fluids.},
  keywords = {{LAOS}},
  booktitle = {},
  journal = {{P}los {N}eglected {T}ropical {D}iseases},
  volume = {10},
  numero = {3},
  pages = {e0004516 [12 p.]},
  ISSN = {1935-2735},
  year = {2016},
  DOI = {10.1371/journal.pntd.0004516},
  URL = {https://www.documentation.ird.fr/hor/fdi:010066776},
}