Umm, what makes you think there isn't a lot of very good data? Start with http://www.cdc.gov/vaccines/vac-gen/side-effects.htm#dtap . I linked to DTaP but there are many others on that page.

To report a problem, go to http://vaers.hhs.gov/index , which is the Vaccine Adverse Event Reporting System.

Did you get any paperwork about the immunization? There should have been a flyer or handout like http://www.cdc.gov/vaccines/hcp/vis/vis-statements/dtap.pdf . This has information both about VAERS, as well as about the National Vaccine Injury Compensation Program.

The "ap" in DTaP vaccine means "acellular Pertussis", which means it uses antigens of the pertussis pathogen rather than whole cells. There should be no infectious material that could cause a bad cough a week later. (It also has fewer side-effects than, but is also less effective than the whole cell vaccine.)

I read that newspaper article you mentioned. It said "Infants under 2 months of age are at the highest risk, accounting for five of Texas' [six] deaths this year" and "80 percent of those were children under 2 months old, who are too young to be vaccinated against the disease."

This is a very different situation than what you are describing, where a cough starts a week after the vaccination. I don't think you can make the inference that it's a side-effect of the vaccination itself based on that article.

The article points out that the new vaccine formulation doesn't seem to be as effective for as long as the old one. What's likely happening is that adults whose immunity has worn off are acting as carriers for the disease, and infecting babies and children who haven't received any immunization for the disease.

This is probably one of the reasons that the Td immunization (DTaP is for children) recommends "All adults should get a booster dose of Td every 10 years."

(While it doesn't confer a life-long immunity, the goal is to prevent pertussis in children; they have the highest risk of death if infected.)

I don't know what to say to you, other than that I, some anonymous person on the internet, agrees with your doctor that "it probably wasn't Pertussis."

> "even considering the low expected rate of serious adverse vaccination events, it is not possible that this clinic has never had a reportable event"

There are different styles of reporting. First off, 25% of the children who receive the DTaP vaccine get a fever, 25% get redness or swelling where the shot was given, and 25% get soreness or tenderness where the shot was given. Your doctor has almost certainly seen those side effects.

But they aren't reported because they are expected. Again, they should be in the handout you got as part of the information about immunization. No doctor is going to report such mild problems.

Then there are the "moderate problems", like seizure, non-stop crying, and a fever of over 105°F. These occur in less than 1:1000 children, which means there should have been a couple of children in your clinic who have had these reactions.

However, it's up to the doctor to decide if this is severe enough to report. The
VAERS guideline include "clinically significant adverse health events following vaccination", "vaccination error [that] may pose a safety risk", "or that the error would be preventable with public health action or education" but "accepts all reports."

These moderate problems are likely not 'significant adverse.' The severe cases seem to happen in 1:1 million cases or rarer for the vaccinations I looked at. Even across all of the vaccinations, it's unlikely that your doctor's office would have had that happen to one of their patients.

So, that's one style of reporting. Another style occurs when they get the above statistics in the first place. In that case, they enroll doctors into the program, and have the doctors report all problems that arise after the vaccination. This can be compared to a baseline reference from children who haven't yet had the vaccine. (Eg, the three weeks before the vaccine compared to the three weeks after.) That's used to weed out coincidental correlations. After all, kids do get sick even with vaccines.

This second style of reporting is what's used to list the known risks of the vaccine, with the first style of reporting use to get information about the very rare cases.

What should the doctor have done to improve your sense of confidence? Run a test for pertussis even though your child didn't have the symptoms for the disease? Make a report even though it wasn't a severe adverse effect? The information you wanted - what to do if there was a severe affect - should have been information you already had. I'm somewhat surprised that the staff didn't know that, since I (an anonymous stranger on the internet) knew it existed, but I also only know your side of the story.