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Testing for AIDS on samples of dried blood prepared on filter papers
Commenf Testing for AIDS on samples of dried blood prepared on filter papers A substattaal rise i~ the number of AIDS ~ s luu I~#n observed ~ tk¢ Past y~ar in ma~y Afrimm e o ~ s , a~l HIV-2 isd~tmoat Wammiuioa and iacmal~ disease. have since gaim~ importance in S~tugal ~. Botk for HIV-I asul HIV-2 diagttosis, ELISA positi~'y is foilot~d by a W#sttm blot test for ~ aMii~lits. Tkt serum m . ~ l e s am m r s d at mb.~ro ttmperautr~s botk d w m g sl~pta~t a ~ u o m ~ wkae a,m~q ~ ~ usti~. At~U lu~ i~ ~ to ~ dt~d blood o~ fdUr paptn for AIDS ~ r , o ~ , in ~ s ~ , ~ ~ ~ and ~0 f r m USA, ~ o ~ with cm'n~Rmml~ serum ~ J . Tk, cMcordaswe kat been good with as almost invariable EU~A cot¢~n~atl~ o~ Western blot, so selectipe lots k¢ amy of tke bamlt in Wtstem blot and Ow Pearson c ~ m value for ELISA ttsti~g o~ serum amt dritd blood loa of O.85. Based on tke dam obtaimd c h u i ~ tkt istt~tio~l txpo~rt of blood. imptzT~ated fdgtr papers, from t~ine HIV-positip¢ and on# HIV-ntgatipe patiant from the USA, to varying temperatures and humidity for ¢~Mtre~t ~ m ~ , bloodcollection on j~ter paper wotdd appear to kave emerged as a tatisfactory procedure for HIV
developed countries would be the ideal nodal point where, apart from mimicking the adverse environment in the laboratory, the stress should be on carriage of impregnated filter papers to the field coupled with rough handling and subsequent retrieval at varying intervals. Utility of dried blood could also be determined for H r v IgM and core antigen, which are typically encountered at the onset of infection. Apart from eliminating any mishaps in AIDS diagnosis, this exercise may provide the missing vital clues for the factor(s) responsible for the continuing immunobiological failures in the developing world 4.
S.C, Arys Prior to universal acceptance of blood collection on filter paper for AIDS diagnosis, it would be desirable to assess the effect on ELISA and Western blot of adverse environments likely to be encountered in the field. Such an exercise has been necessitated because the record of usage and efficacy of different immunobioiogicals in different regions in Africa and Asia has continued to be dismal with high ambient temperatures and tremendous temperature and humidity variation on a particular day playing a detrimental role 3. During a recent appraisal of large outbreaks of
0a4-41 ~ : < , , : ~ o-o~ Io3.oo O 1¢m B u t ~ r ~ a co. (Pubio~) L~. 210
V ~ ,
VOI. 6, June 1988
poliomyelitis in Senegal and Gambia, the overall efficacy of five and 'new' inactivated vaccine was 74 and 69%, respectively, whereas in developed countries both have been 100% efficacious4. Such immunobiological failures have related to cold-chain deficiency, inadequate supervision of field personnel or an unknown heat lability. A similar catastrophe with AIDS diagnosis should be prevented by evaluating the effect of deliberate exposure of blood-impregnated filter papers to every conceivable rigour of temperature, humidity, drought and sunlight. Reference institutions in
M-122 (of part 2), Greater Kailash II, New Delhi 110048, India
References 1 Le Gummo, B., Jun, P., Pegl~ni, M. et a£ Inor~B~g HIV-2 amlodlted AIDS In Sirra2 Farz~, H., Qu~n, T. and Polk, B.F. I:)aoO~nQ a h ' ~ : l t ~ ~o Ix~Bn immunode~kmcy vin~ In driKI bkxxl on mW ~ . J. ~ D~. 1887, l U , 1073 3 Nichoklon, K.G., Burney, M.I., All, S. WKI Peddns, F.T. S t a b ~ of human d ~ str~n ~ v a o d ~ = hlgh amb~nt tom~ . LanoM 1903. I. 916 4 ~ on lhe a'1~dint~1'tatlonll 8a1~Vmron N e ~ 19e7, 3(2). 7
developed countries would be the ideal nodal point where, apart from mimicking the adverse environment in the laboratory, the stress should be on carriage of impregnated filter papers to the field coupled with rough handling and subsequent retrieval at varying intervals. Utility of dried blood could also be determined for H r v IgM and core antigen, which are typically encountered at the onset of infection. Apart from eliminating any mishaps in AIDS diagnosis, this exercise may provide the missing vital clues for the factor(s) responsible for the continuing immunobiological failures in the developing world 4.
S.C, Arys Prior to universal acceptance of blood collection on filter paper for AIDS diagnosis, it would be desirable to assess the effect on ELISA and Western blot of adverse environments likely to be encountered in the field. Such an exercise has been necessitated because the record of usage and efficacy of different immunobioiogicals in different regions in Africa and Asia has continued to be dismal with high ambient temperatures and tremendous temperature and humidity variation on a particular day playing a detrimental role 3. During a recent appraisal of large outbreaks of
0a4-41 ~ : < , , : ~ o-o~ Io3.oo O 1¢m B u t ~ r ~ a co. (Pubio~) L~. 210
V ~ ,
VOI. 6, June 1988
poliomyelitis in Senegal and Gambia, the overall efficacy of five and 'new' inactivated vaccine was 74 and 69%, respectively, whereas in developed countries both have been 100% efficacious4. Such immunobiological failures have related to cold-chain deficiency, inadequate supervision of field personnel or an unknown heat lability. A similar catastrophe with AIDS diagnosis should be prevented by evaluating the effect of deliberate exposure of blood-impregnated filter papers to every conceivable rigour of temperature, humidity, drought and sunlight. Reference institutions in
M-122 (of part 2), Greater Kailash II, New Delhi 110048, India
References 1 Le Gummo, B., Jun, P., Pegl~ni, M. et a£ Inor~B~g HIV-2 amlodlted AIDS In Sirra2 Farz~, H., Qu~n, T. and Polk, B.F. I:)aoO~nQ a h ' ~ : l t ~ ~o Ix~Bn immunode~kmcy vin~ In driKI bkxxl on mW ~ . J. ~ D~. 1887, l U , 1073 3 Nichoklon, K.G., Burney, M.I., All, S. WKI Peddns, F.T. S t a b ~ of human d ~ str~n ~ v a o d ~ = hlgh amb~nt tom~ . LanoM 1903. I. 916 4 ~ on lhe a'1~dint~1'tatlonll 8a1~Vmron N e ~ 19e7, 3(2). 7