Did it Hurt? Vaccine reactions


I have spent most of my MS-life working with Biozzi mice. These were made by Guido Biozzi in Paris to study the genetics of the immune response. At each generation he paired mice making high levels of antibody together and those making low levels of antibody (ABL) after immunization. After about 10-20 generations he made distinct lines. There was the ABH line that made high levels of antibodies that got EAE after immunization and then there are ABL with make low antibody responses and dont get EAE.

I have been bled and swabbed every month since last summer to measure my COVID response and foolishly they have given me £25 every time to do this (Yes what a waste of money!). Now apparently I have been selected to be part of an ABH and ABL study to measure responses to COVID-19 vaccines following assessment of my DNA.

It took 6 goes to get a hepatitits B response (normally you have 3) and have not made a great COVID-19 vaccine response so I am guessing I am in the ABL group, destined for symptomatic COVID-19 (because I dont produce a great vaccine response), when I get infected in the future. So when I am telling you (CD20-depleting antibody and fingolimod) stuff I am telling myself it too?

When I have been vaccinated I have had no adverse effect responses due to the injection, maybe because I have made a crap response, but many people are not like me and get reactions this is called reactogenicity. Now I would say this is not a measure of your antibody response but it could be and if you have demyelinated lesions these can be made more problematic. However, I suspect you are better qualified than I on this I but here are the experiences of other people. But please consider to get your boosters as the adverse effects are laregly temporary

Background and objectives: There are limited data on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine reactogenicity in persons with multiple sclerosis (PwMS) and how reactogenicity is affected by disease-modifying therapies (DMTs). The objective of this retrospective cross-sectional study was to generate real-world multiple sclerosis-specific vaccine safety information, particularly in the context of specific DMTs, and provide information to mitigate specific concerns in vaccine hesitant PwMS.

Methods: Between 3/2021 and 6/2021, participants in iConquerMS, an online people-powered research network, reported SARS-CoV-2 vaccines, experiences of local (itch, pain, redness, swelling, or warmth at injection site) and systemic (fever, chills, fatigue, headache, joint pain, malaise, muscle ache, nausea, allergic, and other) reactions within 24 hours (none, mild, moderate, and severe), DMT use, and other attributes.

Results: In 719 PwMS, 64% reported experiencing a reaction after their first vaccination shot, and 17% reported a severe reaction. The most common reactions were pain at injection site (54%), fatigue (34%), headache (28%), and malaise (21%). Younger age, being female, prior SARS-CoV-2 infection, and receiving the ChAdOx1 nCoV-19 (Oxford-AstraZeneca) vs BNT162b2 (Pfizer-BioNTech) vaccine were associated with experiencing a reaction after the first vaccine dose. Similar relationships were observed for a severe reaction, including higher odds of reactions among PwMS with more physical impairment and lower odds of reactions for PwMS on an alpha4-integrin blocker or sphingosine-1-phosphate receptor modulator. In 442 PwMS who received their second vaccination shot, 74% reported experiencing a reaction, whereas 22% reported a severe reaction. Reaction profiles after the second shot were similar to those reported after the first shot. Younger PwMS and those who received the mRNA-1273 (Moderna) vs BNT162b2 vaccine reported higher reactogenicity after the second shot, whereas those on a sphingosine-1-phosphate receptor modulator or fumarate were significantly less likely to report a reaction.

Discussion: SARS-CoV-2 vaccine reactogenicity profiles and the associated factors in this convenience sample of PwMS appear similar to those reported in the general population. PwMS on specific DMTs were less likely to report vaccine reactions. Overall, the short-term vaccine reactions experienced in the study population were mostly self-limiting, including pain at the injection site, fatigue, headache, and fever.

General Disclaimer: Please note that the opinions expressed here are those of the author and do not necessarily reflect the positions of the Barts and The London School of Medicine and Dentistry, nor Barts Health NHS Trust and are not meant to be interpreted as personal clinical advice.  Please note that Professor Gavin Giovannoni has no responsibility for this blog.

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  • Increased heart rate, bad fatigue, chills, mild fever, headache –> general malaise. Peaked 24h after injection but fatigue lingered about a week, especially after physical exertion:,first day even two flights of stairs was bad, then gradually got better.

    Would not mind overall if it weren’t for the point that I doubt it did much of anything even 3rd go, 6 months after last ocrelizumab round.

  • Good Morning. Or at least it is here in the States. So my own little study. I must be in the ABL group & my daughter in ABH group. Both of us had 2 jabs of Pfizer. She does not have an MS diagnosis but rather has multiple autoimmune signs/symptoms w/possible diagnosis of small fiber neuropathy though I also see alot of signs & symptoms of dermamyositis along w/some form of yet undiagnosed autoimmune stomach issue. Her 1st jab, extreme fatigue, extreme headache. Her 2nd jab was out of control. Extreme headache, extreme fatigue, extreme fever for 3 days of around 104.3° f (40.17°c) with obvious dehydration from fever, chills, body aches. So I’m guessing she had a great response? She was due for a booster end of Oct but we waited due to recent bout of mono.
    I on the other hand rcv’d Pfizer. I have progressive MS, T1d.. Jab 1, I was a little more than usually tired & fatigued. A slight headache. Jab 2 same. Maybe my fatigue a tiny bit more. Other than that, nothing. I’m due for booster end of this month. And as you’ve read in recent comments, my Dad who had severe neurological issues received 2 jabs of Moderna, barely any response to jabs, he recently caught Covid & it ate through him like wildfire taking his life this week. I will try to remember to give an update on my daughter’s vaccine response to booster as we are trying to schedule for this Friday. Thank you MouseDr for continuing to post about Covid as I know some people get pissy rather than just scroll. Yes, I am tired of Covid too but obviously Covid is not tired of us yet. So please, carry on with these posts as they ARE necessary. And when can we start getting the Covid vaccine for our beloved pets?

  • I felt nothing after the first jab, ms flare after second and just a headache so far after the booster yesterday. All Pfizer, no DMT.

  • I have progressive MS and I’m not on any DMT.
    I have had Pfizer for every vaccinations.

    FIRST SHOT very red itchy injection site and heavy arm. Also had slightly elevated liver enzymes.

    SECOND SHOT only a heavy arm. Liver enzymes continue to be raised.

    * I reported this to Biontech and I have heard that some Ms patients at my hospital have reported the same.

    BOOSTER slightly heavy arm but felt exhausted for a couple of weeks and have had ongoing pressure headaches and a sore stiff neck 6 weeks later.

    Have you heard any similar stories of side effects like this?

    I really wish that everyone who were classed as clinically extremely vulnerable could have their bloods investigated to see whether the vaccinations are working for them because if not perhaps they need to go down the route of of preventative medication as it becomes available.

  • Female 65, AZ vaccine – first jab chest pain within hour of jab lasted rest of day managed with panadeine, chills 12 hours after jab, high temperature 15 hours after, headache and weakness lasting 48 hours. Overall I felt very ill. Second jab – no reaction.

    • As part of a National Surveillance Scheme of 150-200,000 people people (What a waste of money to give every on £25) my address was selected at random to be offered testing we get a positive/negative result for PCR and antibdy each month and have to answer a load of questions over and over again. This is due to go on until spring 2022. However, everyone in the UK can be tested for antigen as we get free lateral flow tests and I regularly do this before having contact with the students.

  • First and second jabs AZ, absolutely nothing not even a sore arm. Got a third jab on Saturday (wasn’t really meant to get it because I’m on cladribine but managed to wangle it). Sore arm, and felt a bit fatigued and then feverish after around 48h but not too bad and only for a couple of hours, nothing compared to my partner and my friend who had a booster at the same time… both of them knocked onto their backs for 48 hours.

  • My Covid-19 infection happened more than a year after the last rituximab infusion. The symptoms were mild, recovery was smooth.

    Became eligible for the vaccine soon after recovery and made a good vaccine response. This was over 18 months after the last rituximab dose.
    The timings weren’t planned, but the vaccine became available at the right time.

    Since then, I’ve had another round of rituximab, so the booster is unlikely to be any use for at least several more months.

  • But also,

    Spectrum of neurological complications following COVID-19 vaccination (10/21)


    “COVID-19 vaccines have brought us a ray of hope to effectively fight against deadly pandemic of COVID-19 and hope to save lives. Many vaccines have been granted emergency use authorizations by many countries. Post-authorization, a wide spectrum of neurological complications is continuously being reported following COVID-19 vaccination. Neurological adverse events following vaccination are generally mild and transient, like fever and chills, headache, fatigue, myalgia and arthralgia, or local injection site effects like swelling, redness, or pain. The most devastating neurological post-vaccination complication is cerebral venous sinus thrombosis. Cerebral venous sinus is frequently reported in females of childbearing age, generally following adenovector-based vaccination. Another major neurological complication of concern is Bell’s palsy that was reported dominantly following mRNA vaccine administration. Acute transverse myelitis, acute disseminated encephalomyelitis, and acute demyelinating polyneuropathy are other unexpected neurological adverse events that occur as result of phenomenon of molecular mimicry. Reactivation of herpes zoster in many persons, following administration of mRNA vaccines, has been also recorded. Considering the enormity of recent COVID-19-vaccinated population, the number of serious neurological events is miniscule. Large collaborative prospective studies are needed to prove or disprove causal association between vaccine and neurological adverse events occurring vaccination.”

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