Insects and Disease 629 



spicuous among these tests was that of two English physicians, Sambon and 

 Low, in 1900, in the "malaria-house" in the Roman Campagna. This ex- 

 periment is described by Howard as follows: "Doctors Sambon and Low had 

 constructed a comfortable little five-roomed wooden house about three hours' 

 drive from Ostia, in one of the most malarious portions of the Campagna. 

 The house was tightly built and was thoroughly screened. The experi- 

 menters lived in this house through the period when malaria is most prevalent. 

 They took no quinine and no health precautions beyond the fact that at 

 sundown each day they entered the house and remained there until day- 

 light the next morning. Dr. Rees, of the London School, visited them 

 and occupied the house with them for a portion of the time, and all three 

 conducted laboratory work in one of the rooms, which was fully equipped 

 for such a purpose, and led a busy and contented life. They visited the 

 neighboring villages and investigated outbreaks of the fever in men and 

 cattle. They received and entertained many visitors who were interested 

 in the experiment. They turned indoors before six o'clock and then stood 

 at the windows and timed the first appearance of Anopheles, which would 

 come at a certain hour each evening and try to enter the screened windows 

 and doors. As Dr. Rees expressed it, 'It must have been very tantalizing 

 for them to be unable to get at us.' When the rains set in, every one said 

 that that was the critical time of the experiment. The people in the sur- 

 rounding country generally became feverish and ill, which meant simply 

 that they were all full of malaria, and the chilling caused by the rain brought 

 about an explosion of the fever. The experimenters, however, went out 

 into the rain and got soaked to the skin, but their health remained perfect. 

 Not the slightest trace of malaria developed in either of them; as above 

 stated, the spot where the house was built was probably the most malarious 

 one in the whole Campagna, and it was situated on the banks of one of the 

 canals, which was literally swarming with Anopheles larvae. The prevalent 

 idea that the night air of the Campagna is in itself so dangerous was included 

 in the experiments, and the windows were always left open at night, so that 

 if the marsh air had anything to do with malaria they would have contracted it. 

 " A check experiment was carried on at the same time. Anopheles 

 mosquitoes which had been fed on the blood of a sufferer from malaria in 

 Rome, under the direction of the Italian authority Bastianelli, were sent 

 to London early in July. A son of Dr. Patrick Manson, the famous inves- 

 tigator who first proved the transfer of filaria^ by mosquitoes, offered himself 

 as a subject for experiment, and allowed himself to be bitten by the mosquitoes. 

 He had never been in a malarious country since he was a child, but in due 

 time was taken with a well-marked malarial infection of the double tertian 

 type, and microscopical examination showed the presence of numerous para- 

 sites in his blood." 



