As mentioned before, whooping cough can be pretty hard on children, especially young ones. In this article from 1938, Robert Cruickshank discusses whooping cough and how it compares to some other diseases in the UK at the time.
What Should We Call...
"Whooping cough" is the common term, referring to the shrill intake of air after a bout of intense coughing, but Cruickshank pointed out that even in severe cases of the infection, not all patients actually whoop. And since just "cough" or maybe "whooping and/or non-whooping cough" don't work too well, he suggests "pertussis" as a good alternative. On the other hand, as I discussed in 079, this could cause some confusion too, since not all cases of coughs with whooping are caused by B. pertussis. But obviously both names have stuck with us throughout the years.
Mortality
Different people had different estimates of how many people died from whooping cough. The case-fatality rate seemed to be between 1 and 8.5%, generally higher for younger patients. Though in Glasgow, the reported rate was 27%, and up to 44% for those less than a year old. Pretty bad.
For comparison, the rates for measles, diphtheria, and scarlet fever were 5%, 4%, and 0.4% respectively. So pertussis was the fourth leading cause of death in London ages 0-5 years, killing 434 people per year. The three leading causes were congenital causes, pneumonia, and diarrhea (presumably infections of unknown etiology). Measles was 5th.
Though despite these numbers, the death rates for these diseases had actually been decreasing over the past 70 years, at least for younger children. Cruickshank doesn't discuss why this might be. Could be better treatments, supportive care, immunization (at least for diphtheria), increasing public health in general... not clear.
Prevalence
Keeping track of cases of whooping cough wasn't mandatory throughout the UK at this time, though some areas did so. So it was only possible to estimate the prevalence. Some estimated that 44% of children in London got pertussis before age 5, and 60% by age 10. Measles was similar, diphtheria and scarlet fever less so.
In England, it seemed like pertussis came in two-year intervals, though it seemed different in other countries. This seemed to be because of the addition of susceptible people to the population (newborns), but could also because immunity after infection didn't last too long (possibly only a year; I wasn't clear on this part).
Lab Tests
It was pretty clear at this point that B. pertussis caused whooping cough (most of the time), not some virus. People infected with these bacteria developed antibodies, and antibodies produced from vaccination correlated with immunity to infection. Cruickshank discusses methods for diagnosis, those that work and those that don't.
Treatment and Prevention
Cruickshank says: "Pertussis is a disease of which it may be said that the multiplicity of remedies is an index of therapeutic failure." I think what he means is there a lot of suggestions but not many that actually seem to work. Probably like what I discussed in 078. Supportive care is good, of course, and anything that helps children breathe better. Some thought vaccine therapy or antiserum worked well, especially in the early stages of disease, but it didn't seem clear.
For controlling spread, Cruickshank mainly recommended keeping infected patients away from susceptible children, which makes sense. Pertussis isn't as contagious as measles or chickenpox, for example, so it wouldn't be too hard, even in hospitals. He thought that patients shouldn't be contagious anymore after the 4th week of disease.
If isolation of cases were impossible in any situation, he recommended vaccination as something that seemed effective. He cited Madsen's data (069) and Sauer's, showing effectiveness of their vaccines. But in the interest of more solid data, he recommends a more controlled study, and possibly a program similar to the one in place for diphtheria at the time.
Overall, not much new here, but an interesting perspective.
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