[quote NotBot]@IndigoC - I have a masters in immunology. That’s categorically not true in the case of minor illness such as a cold or minor stomach troubles etc. Your body is more than capable of dealing with a cold and a vaccination. Where are you getting this idea from that it’ll give a lower immune response? God knows how much medical data on vaccines I’ve studied in my life & I can say with enormous confidence that the reason they tell you to get vaccinated with minor illness us because no data has shown a reduced response of any concern.
A severe infection/illness such as confirmed flu or a severe fever, yes. There could be a reduced response from your immune system. But even this is minor to be honest & the jury is somewhat out. Precaution is given to moderate illness more so to remove the element of confusion around symptoms. a patient believing symptoms of the illness For example, if a patient has a fever of 38 and after the vaccine, this rises to 39 & they develop a rash.. is it the vaccine or would this have happened regardless due to the already present illness. A rash could be meningitis & the patient may ignore it believing it to be vaccine related. Or the patient may report the rash as a vaccine side effect when actually, it’s the pre-existing illness getting worse.
I’ll try link up some accessible research on vaccines & contradictions. & please get your second vaccine unless you are feverish. Your immune response will be just fine![/quote]
My understanding is the actual studies on it are unclear. This seems to be standard advice for the flu shot:
However, if you are sick when you are vaccinated, your immune system is already hard at work trying to fight the germs that have caused that illness. This means it will be harder for your body to develop antibodies to the flu virus at the same time. It could even mean that it will take longer for you to recover from your illness as your immune system tries to do double-duty.1
Reduced Response to the Flu Vaccine
If your body is busy fighting off a different infection, it may not develop strong enough antibodies to the strains of influenza in the vaccine like it would if you were well. This could result in an increased chance that you could still get the flu.
www.verywellhealth.com/what-will-happen-if-i-get-a-flu-shot-while-im-sick-770545
Fever seems to be the usual baseline for holding off but personally I’d want the best response possible given the seriousness of Covid and I wouldn’t want to worsen an existing illness. But I’m also the sort of person that doesn’t drink alcohol when I’m ill and that seems to be a national sport here.