Elementary bacteriology and protozoölogy : the microbiological causes of the infectious diseases / by Herbert Fox.

  • Fox, Herbert, 1880-1942.
Date:
1913
Catalogue details

Licence: In copyright

Credit: Elementary bacteriology and protozoölogy : the microbiological causes of the infectious diseases / by Herbert Fox. Source: Wellcome Collection.

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    insect is only capable of depositing it in a bite when twelve days shall have elapsed since it bit a yellow fever patient. More than that, five days elapses between the bite of the mosquito and the appearance of the virus in the patient’s blood. Furthermore, the patient’s blood only remains infective for three days. The virus is so small that it will pass through the unglazed porce- lain filters used in the laboratory. Because of these facts the modern conception of yellow fever supposes a protozoon as the cause. There are no laboratory diagnostic measures nor as yet any specific treatment. The spread of yellow fever is prevented by destroying the breeding places of the mosquito, a difficult thing, since this insect breeds in lowlands and bushes and in houses. It bites usually in the late afternoon. Scarlet Fever and Measles.—These two easily com- municable diseases are transmitted apparently by the virus cast off in scales from the skin. Nevertheless the specific causative agent is unknown. It has lately been shown that measles is transmissible to monkeys at some particular time of the disease, which appears from present knowledge to be quite early. The most recent researches fail to show that measles scurf will carry the disease to monkeys. Streptococci were once thought to be the cause of scarlet fever. It would seem from results obtained within the last year that these organisms may be exonerated. Typhus Fever.—Although this condition is not under- stood clearly, it now seems that body lice, flies, and ticks transmit it. Poliomyelitis.—This is an acute apparently infectious disease characterized by a mild constitutional illness