CHAPTER XXXVI 



LABORATORY METHODS IN MALARIA: THE IN- 

 FECTION AND DISSECTION OF MOSQUITOES 



By 



M. A. Barber 

 U. S. Public Health Service 



Anopheles are infected with malaria in the laboratory for vari- 

 ous purposes : to determine the susceptibility of an anopheline 

 species to malaria, to measure the effect on gametocytes of a drug 

 or treatment, to obtain infected mosquitoes for the treatment of 

 progressive paralysis, or to obtain material for teaching purposes. 

 The requirements of experiments will vary more or less according 

 to the purpose for which they are made ; but in nearly all cases it 

 is necessary to have a plentiful supply of mosquitoes available for 

 feeding on gametocyte-carriers. 



Anopheles may be collected in the adult stage in daytime resting 

 places, where they often occur in large numbers. Such mosquitoes 

 are suitable for some experiments ; but in a malarious region speci- 

 mens may be already infected and may thus introduce a serious 

 error into the experiments. 



Mosquitoes which have emerged in the laboratory are more 

 suitable for infection experiments. They are best collected in their 

 natural habitat when they have reached the stage of full-grown 

 larvae or pupae. Small larvae may be reared to normal maturity in 

 artificial breeding places, but it is usually possible to find a nat- 

 ural breeding place where older specimens are already present. 



A great variety of mosquito cages have been described. I pre- 

 fer for most purposes a cage made of a small glass lantern-chim- 

 ney, about four inches in diameter and four inches high (Dietz 

 ''Little Wizard," clear glass). The ends are covered with bobinet 

 or other mosquito netting. If the chimney does not have a rim for 

 tying on the bobinet, one can be made by laying a thick piece of 



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