The status of typhus fever was studied by the complement fixation test with an antigen of Rickettsia prowazeki in four small towns of the southern part of Colombia. In the towns selected for study the disease has been endemic for many years and its evolution may have been natural because of the poor sanitary conditions under which the inhabitants live.
In 1945 a representative sample of the population (5–49 years of age) from the urban and suburban zones of Guachucal, Aldana, and Pupiales was examined. The total population of these zones was 4,490; 966 different serums were tested.
It was found that about a fourth of this population had been attacked by typhus at some time; and that the disease may affect children as young as 5 years of age.
The results obtained with the test indicate that there is no statistically significant difference in the way typhus attacks males and females and the various age groups studied.
The analysis of the data of the towns taken separately suggests that there was a recent epidemic in Aldana, and that Guachucal had a higher incidence among women than men. However, the significance of these conclusions loses a great part of its value because the populations are so small.