ABSTRACT
An ELISA technique was developed using samples of Schistosoma japonicum-infected human whole blood based on the conventional ELISA. In this study, the following were demonstrated. 1) Whole blood samples could be used. 2) The volume of whole blood and conjugate could be reduced to 0.05 ml. 3) The incubation time was shortened to 5 minutes. 4) The optical density could be measured at 10 minutes after transferring the substrate and the volume was reduced to 0.1 ml. 5) It did not require a fixed temperature setting. 6) The operation time was as short as 20 to 30 minutes. 7) The optical density values were almost the same as the conventional ELISA and were not influenced by other common intestinal helminthic infections. 8) The observed variations from day to day including effects of sampling in stool examination were negated by the results of this ELISA technique. 9) Based on correlation with stool examination results, criteria can be formulated in which optical density values of 0.3 and above as positive, 0.1 to less than 0.3 as doubtful, and less than 0.1 as negative. Whenever an immunological field survey is necessary, before and after a selective or a mass treatment control program, this WHOLE BLOOD-ELISA, which was shown to be rapid and simple, is recommended.
Subject(s)
Antigens, Helminth/blood , Enzyme-Linked Immunosorbent Assay/methods , Schistosoma japonicum/immunology , Schistosomiasis/diagnosis , Adolescent , Adult , Aged , Animals , Child , Child, Preschool , Female , Humans , Male , Mass Screening , Middle Aged , Schistosomiasis/bloodABSTRACT
PBS-Tween as a wash solution, prepared with distilled water, is used in ELISA. In areas where schistosomiasis is endemic, however, distilled water is hard to come by. We have modified a WHOLE BLOOD-ELISA test to use coconut water-Tween as a wash solution, because coconut water is easy to come by and cheap in the tropics. We applied the test to whole blood samples from rabbits and humans infected with Schistosoma japonicum. This modified WHOLE BLOOD-ELISA was confirmed to be a rapid, simple, and cost-effective method.
Subject(s)
Cocos , Enzyme-Linked Immunosorbent Assay/methods , Schistosoma japonicum/isolation & purification , Schistosomiasis/diagnosis , Animals , Humans , In Vitro Techniques , Mass Screening/methods , Rabbits , Schistosoma japonicum/enzymology , Schistosomiasis/blood , Schistosomiasis/enzymology , Serologic Tests/methods , SolutionsABSTRACT
A descriptive study was carried on the schistosomiasis problem in the Philippines from the time the disease was discovered in 1906 to the latter part of the 1990 s. Some research findings were reviewed including the nature of the disease itself. Based on the thrust of the control program which is centered mainly on selective mass treatment and progressed to disease stratification and mass treatment using praziquantel, a downward trend in the prevalence of the disease was observed-from an average of 10.4% in 1981-1985 to 4.1% in 1996. Recommended prospective action, among others, include the development of strategies on environmental sanitation and snail control/eradication in the thrust of the schistosomiasis control program. Other policy related concerns should be formulated subject to the results of further research activities such as on (a) chemotherapy; (b) drug delivery schemes; (c) diagnosis; (d) search for a safe, economical and effective chemical(s) for vector control; and (e) prophylaxis and vaccine production for protection against infection for disease modulation or reduction of pathology.
