It seems to be the age of whooping cough vaccine testing, at least in this blog. This is another.
Given other questionable results (065), though not with Sauer's vaccine exactly, Siegel and Goldberger decided to do a more controlled trial, in the Sea View Hospital for people with tuberculosis. This place had a bunch of children with TB that were kept together by age and sex (after a certain age), with limited contact with the outside world. Since they were monitored and isolated, pertussis would be easier to track among them.
So Siegel and Goldberger got vaccine from Sauer and Eli Lilly, and vaccinated a total of 101 children over 2 years, keeping a second group as controls. They stopped vaccinating when an outbreak of pertussis occurred in the hospital. Sixty-four children in total were exposed over 3.5 months, and there were 27 definite cases of characteristic whooping cough. The staff isolated each child when they started having symptoms of course, but symptoms don't show up until after the child starts being able to spread the bacteria to their playmates. Another 5 children got sick but didn't have the characteristic whoop, so they were counted as probable cases.
At the time of the outbreak, the average age of vaccinated children was 4.2 years, vs. 2.3 years average for controls. This is a big difference, and could affect the results. The groups didn't have significantly different severity of tuberculosis though.
There were only 36 children in the final study, too: 17 vaccinated and 19 controls. The others either had left the hospital, or had certainly or possibly encountered pertussis previously (and thus maybe had some natural immunity). They only considered those with no known history.
So now for results: considering only definite cases, vaccinated did better, 29% (5 of 17) getting sick, vs. controls with 53% (10 of 19). 44% decrease. Not very good at all. Especially when adding in probable cases, which brought the numbers up to 53% vs. 58%.
Most of these cases were mild; there was one moderately severe case among the vaccinated, and four more in the controls. Pertussis didn't seem to aggravate TB in either group. The average durations of whoop and severe period in the vaccinated group were 21 and 2.8 days, vs. 32.5 and 7.5 days in controls. And considering more of the cases in the vaccinated group weren't even certainly whooping cough, it seemed like the disease was less severe in those vaccinated. However, these children were older too, so it's possible the age might've contributed more than the vaccine to this effect.
So these aren't great results for the vaccine, especially considering the lack of blinding or placebo. It's possible some things complicated the results: having tuberculosis may have increased the children's susceptibility, but according to studies of antibodies, they seemed to respond to the vaccine as well as normal children do. Also, being so closely intimate in the hospital setting, there might've been just too heavy an exposure to the pathogen for the vaccine to be adequate. But it seems like if it were a good vaccine, that shouldn't be an issue. So, more work to do perhaps.
Citation: Siegel, M. & Goldberger, E. W. Active immunization of tuberculous children against whooping cough with Sauer’s vaccine. JAMA 109, 1088–1092 (1937).
Given other questionable results (065), though not with Sauer's vaccine exactly, Siegel and Goldberger decided to do a more controlled trial, in the Sea View Hospital for people with tuberculosis. This place had a bunch of children with TB that were kept together by age and sex (after a certain age), with limited contact with the outside world. Since they were monitored and isolated, pertussis would be easier to track among them.
So Siegel and Goldberger got vaccine from Sauer and Eli Lilly, and vaccinated a total of 101 children over 2 years, keeping a second group as controls. They stopped vaccinating when an outbreak of pertussis occurred in the hospital. Sixty-four children in total were exposed over 3.5 months, and there were 27 definite cases of characteristic whooping cough. The staff isolated each child when they started having symptoms of course, but symptoms don't show up until after the child starts being able to spread the bacteria to their playmates. Another 5 children got sick but didn't have the characteristic whoop, so they were counted as probable cases.
At the time of the outbreak, the average age of vaccinated children was 4.2 years, vs. 2.3 years average for controls. This is a big difference, and could affect the results. The groups didn't have significantly different severity of tuberculosis though.
There were only 36 children in the final study, too: 17 vaccinated and 19 controls. The others either had left the hospital, or had certainly or possibly encountered pertussis previously (and thus maybe had some natural immunity). They only considered those with no known history.
So now for results: considering only definite cases, vaccinated did better, 29% (5 of 17) getting sick, vs. controls with 53% (10 of 19). 44% decrease. Not very good at all. Especially when adding in probable cases, which brought the numbers up to 53% vs. 58%.
Most of these cases were mild; there was one moderately severe case among the vaccinated, and four more in the controls. Pertussis didn't seem to aggravate TB in either group. The average durations of whoop and severe period in the vaccinated group were 21 and 2.8 days, vs. 32.5 and 7.5 days in controls. And considering more of the cases in the vaccinated group weren't even certainly whooping cough, it seemed like the disease was less severe in those vaccinated. However, these children were older too, so it's possible the age might've contributed more than the vaccine to this effect.
So these aren't great results for the vaccine, especially considering the lack of blinding or placebo. It's possible some things complicated the results: having tuberculosis may have increased the children's susceptibility, but according to studies of antibodies, they seemed to respond to the vaccine as well as normal children do. Also, being so closely intimate in the hospital setting, there might've been just too heavy an exposure to the pathogen for the vaccine to be adequate. But it seems like if it were a good vaccine, that shouldn't be an issue. So, more work to do perhaps.
Citation: Siegel, M. & Goldberger, E. W. Active immunization of tuberculous children against whooping cough with Sauer’s vaccine. JAMA 109, 1088–1092 (1937).
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