
advances in filariasis
especially concerning periodicity of microfilariae
a review is given of some advances in our knowledge about filariasis during the
past ten years.
it is urged that investigations should be continued on methods to facilitate
the control of filariasis in large populations, by means of
diethylcarbamazine--e.g. incorporation of the compound in cooking salt, as
was done with chloroquine against malaria.  furthermore, steps should be taken
to protect young people against filariasis by systematic treatment in the
schools.
in order to understand the cyclical disappearance of microfilariae from the
peripheral blood and their accumulation in the lungs, the movements of
microfilariae in the pulmonary capillaries has been studied by cinematography.
apparently their accumulation in the lungs is not due to mechanical retention,
but perhaps they migrate round and round in the pre-capillary network of
arterioles.
the periodicity of microfilariae is best considered as a biological rhythm.
apparently the microfilariae have a circadian rhythm of their own which is
entrained and synchronized by stimuli from the circadian rhythm of the host.
judging by experiments with monkeys containing microfilariae of edesonfilaria
malayensis, the most effective of these stimuli from the host seems to be the
rhythmic variation of body temperature which occurs every 24 hours.
