“School” refers to all children and adolescents who were reported as attending school.
“Home” includes not only the housewife, the housekeeper, but also servants and invalids; all who in their daily routine spend the greater part of the time in the home.
“Manual Indoors” refers chiefly to laborers in factories and includes all manufacturing occupations in which the work is of a manual character no matter what the particular branch.
“Manual Outdoors” refers to such occupations as ditch diggers, street cleaners, conductors and motormen, longshoremen, trucksters and teamsters, telephone and telegraph linemen, etc.
“Retail Sales Indoors” refers to clerks in stores and all other individuals who, working indoors, come into about the same degree of contact with the public-at-large.
“Retail Sales Outdoors” includes sales agents, life insurance agents, traveling salesman, pedlers, newsboys, etc.
“Office,” officials, secretaries, stenographers, telephone operators, telegraph operators, etc.
We have observed that in 1918 infants presented the lowest incidence and school children the highest. Occupations designated Home and Office were surprisingly high. Children also showed a high incidence, one out of every five developing the disease. The records show that manual labor, both indoors and outdoors, was associated with a higher incidence than less strenuous work, as retail sales, indoors and outdoors (Chart XXIII).
The attack rates in most of the occupations are so nearly the same as to lead to no certain conclusions. It would appear from our records that individuals working out of doors were less frequently attacked than those whose occupation kept them in doors. The groups at the two extremes of incidence correspond to what we should expect when considering opportunities for contract. The infant has least direct contact. His contact is only with one or a few individuals, the mother or the nurse. This group developed the disease in 5.8 per cent. The school child not only has the same degree of contact as do adults, but also in the tussle and scramble of play the contact becomes much closer. The factor of age plays a large part in the occupational distribution and the apparent occupational susceptibility is influenced by the age susceptibility.
When we consider the occupational incidence in the various districts we find that the only constant feature in the relatively small groups is the low incidence among infants (Chart XXIV).