ABSTRACT
Objective To observe the degeneration of Brugia malayi in Meriones unguiculatus model. Methods Microfilaria of Brugia malayi derived from Meriones unguiculatus was used to infect Anopheles sinensis . Infective stage larvae (L 3) from mosquito vector were collected and inoculated into abdomen of Meriones unguiculatus. Successive 33 generations of the parasite in the rodent model have been observed. Results Since 1974 when the animal model was established, the parasite has lasted for 33 generations, the positive rate of Meriones unguiculatus with microfilaria gradually reduced from 80% of the 28th generation to 16% of the 32nd generation and finally to 0 at the 33rd generation. Conclusion It became difficult for the larvae of Brugia malayi to develop and/or reproduce in the animal model after multiple inoculations for generations.
ABSTRACT
The methods adopted in this paper were as follows: (1) The cost of the filariasis control was estimated to be direct cost and indirect cost; (2) Using the reduction rate of acute inflarrlmatory attack as the measurable indicator of control effectiveness; (3) Estimating the case number of acute inflammatory attack occurred after control year by year basing on the goodness by fitting in the reduction trend of acute inflammatory attack with hyperbola formula; (4) Assuming that the case number of acute inflammatory attack would be relatively stable at the same level of pre-control if filariasis control measures were not implemented;(5) The benefit from the filariasis control was estimated by transforming the increasing manworking day and sav1ng the mediclne expenses of patients due to the reduction of acute inflammatory attack. By allowing seven percent discount on cost and benefit, the total cost was 21 182 Yuan, the total benefit was 119 859 Yuan, the ratio of cost-benefit was 1: 5. 7,implying that putting in one Yuan to filariasis control in this township may gain benefit 5. 7Yuan.