So what's the latest news on whether the H1N1 booster is needed?

[ett]

So DS2 got the H1N1 vaccine at the allergist's office today. (due to his egg allergy.) They only do the first dose at the allergist's office (due to limited supplies) and if that goes well, we can do the second dose at the ped. So what is the current recommendation as to whether the booster shot is needed? My husband told me that there is new research that the second dose is not needed and my mother also mentioned hearing the same thing.

Due to the egg content, the second dose has to be the same manufacturer as the first dose so I don't even know if I will be able to find it. I'm just wondering if the first vax will be useless if I can't find the second dose.

Thanks!

[MoJo]

When I got my DD her H1N1 vax at the county clinic Tuesday, the nurse actually ran after me, saying, "Hey, did we tell you she needs another one in 28 days?" They hadn't told me that, but I already knew it from all I've read here.

So I assume that's still the recommended course of action.

[egoldber]

The CDC has not changed it's recommendations.

There was some press recently that the WHO is saying that one dose is "sufficient", but sufficient in the sense that from their perspective it's better to give more people some protection that a smaller number of people the best protection.

[mommylamb]

I read (and I may be slightly off with the percentages here) that for children under age 3, the first shot only gets them 28% immune, with 100% after the second shot. Children older than 3 but under 10 were testing at 55% immune after the first shot and 98% immune after the second (I remember thinking that it was strange that it wasn't 100 percent, which is why the 98% sticks out). I'll have to find where I read this.

[mecawa]

Our ped told us one dose was better than nothing, but that they needed two (if under age nine I think) to be totally covered for the season.

The ped also said there had to be 4 weeks apart between getting the initial shot and then the booster, although I had read on somewhere (I swear it was the CDC's website, but I don't know how they could have been wrong, LOL) it was three weeks.

[egoldber]

(I remember thinking that it was strange that it wasn't 100 percent, which is why the 98% sticks out

No vax confers 100% immunity for all people. The numbers you cite agree with what I recall. The info is all on the www.flu.gov website, you just need to dig into the clinical sections of the site to find the studies.


(I swear it was the CDC's website, but I don't know how they could have been wrong, LOL) it was three weeks.

The CDC recommends the spacing to be "about 28 days" but an interval of 21 days is "considered valid".

[jenmcadams]

We were able to get the vac for our kiddos (age 4 and 7, not high risk) at a local grocery store Little Clinic a week ago and they actually reserved the 2nd dose for us (put it away in a fridge with our name on it). The nurse practitioner said that it was definitely recommended.

[mominmarch]

Our ped told us that the first dose gets you 70% immune (after a week's time) and the second dose 97% immune. I think this was actually posted on a sign at the health department in our city actually too.

[egoldber]

The data on efficacy after one shot can be found here:

http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5839a3.htm

Here is an excerpt:


Among children aged 6--35 months, 3--9 years, and 10--17 years immunized with a 15 μg inactivated influenza A 2009 (H1N1) monovalent vaccine (Sanofi Pasteur, Inc., Swiftwater, PA), 25%, 36% and 76%, respectively, developed antibody titers of 1:40 or more (hemagglutination-inhibition assay) after a single dose of vaccine.â€* Immunogenicity and safety study results similar to those observed for seasonal vaccines also have been reported by the other manufacturers (MedImmune LLC, Gaithersburg, MD and Novartis Vaccines and Diagnostics, Limited, Liverpool, UK, unpublished data, 2009).

So in essence what this says is that with the inactivated vaccine (aka the "shot") here is the breakdown:

Children aged 6-36 months, 25% had sufficient anitbodies after one dose
Children aged 3-9 years, 36 % had sufficient anitbodies after one dose
Children aged 10-17 years, 76% had sufficient anitbodies after one dose

By comparison, 97% of adults had sufficient antibodies after one dose.

I know I've seen this info for the mist as well, but I can't find it on first search.

[wendibird22]

Our ped is still recommending 2 doses. DD is due for her 2nd dose tomorrow but the ped isn't permitted (by our state gov't) to give it to her even though they have supply on hand until all their patients get dose 1. Of course, that means they are holding onto a supply for a hypothetical need since they likely have a population of patients who will chose not to receive it.

So, I had to track down the vax at my health department in order to get DD the booster next week.

[set81616]

Do they need the second dose if they got H1N1 a week after the first dose?
Thanks,
Shannon

[stillplayswithbarbies]

what about older kids and adults who are getting their first flu shot of their life? Do they (me!) need a booster?

[wencit]

what about older kids and adults who are getting their first flu shot of their life? Do they (me!) need a booster?This is my situation too, and I asked the nurse about it, who said no. Even if this is the first time in your life getting a flu shot, you don't need a booster. I'm not sure if this applies to older kids, though.

[ett]

This is my situation too, and I asked the nurse about it, who said no. Even if this is the first time in your life getting a flu shot, you don't need a booster. I'm not sure if this applies to older kids, though.

Yeah, I thought the second booster only applied to kids under 10.

[ett]

The data on efficacy after one shot can be found here:

http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5839a3.htm

Here is an excerpt:



So in essence what this says is that with the inactivated vaccine (aka the "shot") here is the breakdown:

Children aged 6-36 months, 25% had sufficient anitbodies after one dose
Children aged 3-9 years, 36 % had sufficient anitbodies after one dose
Children aged 10-17 years, 76% had sufficient anitbodies after one dose

By comparison, 97% of adults had sufficient antibodies after one dose.

I know I've seen this info for the mist as well, but I can't find it on first search.

Thanks for the numbers. There is so much information out there that sometimes you just can't find the important stuff.

[Mirthful]

The National Institutes of Allergy and Infectious Diseases (NIAID), the arm of the National Institutes of Health (NIH), who is running the clinical trials for the H1N1 vaccine released more results on November 2nd which show better numbers for the first dose in the 3-9 year old group and the 10-17 year old group than the first set of numbers they released in late September.

link: http://www3.niaid.nih.gov/topics/Flu/H1N1/Research/children.htm


An excerpt: (sorry! I don't know how to do that cool put-the-quote-in-a-box thingy!)

Data obtained eight to 10 days after the second vaccine dose compared with results obtained 21 days after their first vaccine dose were as follows:

* Among the youngest children (6 to 35 months), 100 percent had a robust immune response after the second 15-microgram dose compared with only 25 percent three weeks after the first dose.
* In children aged 3 through 9 years old, 94 percent had a robust response after the second 15-microgram dose compared with only 55 percent three weeks after the first dose.
* In general, the immune responses in children receiving two 15-microgram doses and those receiving two 30-microgram doses of vaccine were similar, suggesting that receipt of two 15 microgram doses is adequate to elicit a strong immune response.

The trial data continue to support the recommendation that children 9 years of age and younger should receive two 15-microgram doses of 2009 H1N1 vaccine.



So, to summarize:
Children 6-35months old: 25% immune after 1 dose, 100% immune after second
Children 3-9 years old: 55% immune after 1 dose, 94% after second dose

Another part of the press release mentions:
Children 10-17 years old: 94% immune after first dose

So, for your younger son, I'd definitely get the second dose!

oh and link for the 21-days-is-okay spacing (see Questions #2 and 3):
http://www.cdc.gov/H1N1flu/vaccination/top10_faq.htm