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Thai researcher details her Covid-19 vaccination experience

Tanutam Thawan



PHOTO:Aecc Global

“General post-vaccination symptoms include a mild fever, headache, muscle pain and shivering.”

A Thai post-doctorate researcher at the University of Chicago is detailing her Covid-19 vaccination experience and offering insight into its effects. Siriruk Changrob has received 2 doses of the Pfizer-BioNTech vaccine but says just the vaccine won’t immunise people from getting Covid.

Siriruk says a person who is inoculated with the vaccine can still become infected and should continue to practice social distancing and wearing a mask until a herd immunity is developed by 60% of the population, or the virus dissipates. She says she received the first vaccine about 20 days ago and upon arriving for the 2nd dose, a nurse asked her about any side effects and whether she had tested positive for the virus in the past 90 days.

She says she didn’t feel anything until about 8 hours after the 2nd injection, when she started to feel feverish and some pain at the injection site. She noted that all her colleagues warned her that the 2nd injection would give her more painful symptoms.

The Pfizer vaccine requires 2 doses that must be administered at least 21 days apart. But Sriiruk warns that if you can’t get the 2nd injection within the recommended time frame, to hold off from the injection until the time frame can be followed. She also said that anyone who requires daily medication to treat other ailments should consult their doctor before being vaccinated, to ensure that the efficacy of the vaccine will not be affected by that medication.

She says the general post-vaccination symptoms include a “mild fever, headache, muscle pain and shivering”, positive signs that the body is developing an immunity. She warns that taking medication to prevent such symptoms as a fever, is not recommended as the vaccine only protects a person from developing symptoms, rather from being infected by the virus.

SOURCE: Thai PBS World


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  1. Avatar


    Sunday, January 24, 2021 at 8:38 pm

    ‘can still spread after vaccinated she says’. Ok sheeple, the virus spreads by getting into the body and then multiplying. The more copies the virus makes the easier it is to give to others. In people who have been vaccinated or have gotten sick, the body has produced defenders called antibodies which bind to the invader and prevent the majority of it from ever multiplying or causing symptoms. While theoretically it is possible to pass the virus to someone else after vaccinated, it is not very likely. At some point, we must give up the idea that everyone can and should live forever at get back to life.

    • Avatar

      Issan John

      Sunday, January 24, 2021 at 9:05 pm

      She’s a medical doctor doing post-doctorate research; all the experts who’ve commented on this so far either agree with her or say that it’s not been tested, varies depending on the vaccine, and is not yet known particularly with mRNA vaccines.

      Since you evidently disagree, just to make sure that I can balance their collective expertise against yours, would you mind explaining your own medical qualifications?

      • Avatar

        Sam Charles

        Wednesday, January 27, 2021 at 1:35 pm

        Yes I’d also love to hear about his expertise/qualifications

        • Avatar


          Sunday, February 21, 2021 at 3:01 pm

          Me too !

  2. Avatar


    Sunday, January 24, 2021 at 8:51 pm

    Unfortunately there is a lot of misinformation circulating in re to the various vaccines. Once the 2d shot is given & the vaccine becomes effective in 14-18 days, it WILL prevent in 90+% of the time infection as well as the spread of infection from the person vaccinated to others. The reasons health care providers want persons to continue to mask and continue to social distance is to encourage others, who have not been vaccinated, to continue to do the same; and to also account for those 5% or so persons who the vaccine is not as effective.

    I am also curious as to how the Chicago researcher moved to the front of the line. At this time only health care workers & seniors can get vaccinated. Perhaps she falls into one of those categories.

    • Avatar

      Issan John

      Monday, January 25, 2021 at 12:27 am

      Agreed 100%, Marv, there’s an enormous amount of misinformation around.

      Just to clarify things, could you possibly give the source of your information that 90%+ of the time the Pfizer vaccine “prevents the spread of infection from the person vaccinated to others”?

      I can’t find any reliable or informed source that says that, but maybe I’ve missed it.

      • Avatar

        London Al

        Monday, January 25, 2021 at 7:18 am

        There is zero evidence a vaccinated person can spread the virus whilst not having it, I wish someone would explain to me how that is possible, how about you Dr John?

        • Avatar

          Issan John

          Monday, January 25, 2021 at 11:03 am

          It’s hardly complicated.

          The vaccines, as they are at the moment, do NOT stop you being infected.

          All the manufacturers and independent researchers say they do is stop the infection developing.

          Nothing else.

          • Avatar


            Tuesday, January 26, 2021 at 3:32 pm

            So if they DON`T stop you being infected that means that you CAN still be infected, therefore how is it that that they DO stop the infection as you say “all manufacturers and independent researchers say” ??? lt`s NOT clear at all, in fact it`s contradictory !

    • Avatar


      Monday, January 25, 2021 at 3:11 am

      I’m following this news closely and haven’t heard any definitive news that once vaccinated you can’t spread infection from the person vaccinated to others. So it appears this isn’t a finding from a study and is your opinion. If this were based on science Thailand would open up without quarantine to the vaccinated asap.

      I’ve heard from medical professionals that you should continue to wear masks and social distance because they haven’t proven a vaccinated person can’t infect others.

      Marv, I’d love to be wrong. Where did your conclusions come from?

      • Avatar

        Issan John

        Monday, January 25, 2021 at 11:32 am

        Actually, Billy, while you’re right that a postdoctoral researcher doesn’t necessarily have to be a “medical doctor”, she most certainly is one.

        … and while you’re also right that having “had the vaccine hardly makes her qualified to proclaim that a vaccinated person can get and spread the disease etc …“, her research into virology and vaccinations, with the last 12 months spent researching Covid-19 at the University of Chicago, makes her eminently well qualified to do so.

        It actually makes her one of the best “qualified” people in the world to do so, as you would have found out if you’d spent a few minutes checking her background and qualifications instead of dismissing her because she’s “Thai” which makes her “irrelevant”.


        • Avatar


          Monday, January 25, 2021 at 3:25 pm

          Actually, no, Johnny Boy. She is not an MD. She is a researcher with a PhD in Philosophy. I am not questioning her reputation as a scholar or an academic or that she has a right to share her inoculation experience. But what is the news in this story? Is it that a Thai person experienced the vaccine and is sharing her experience? Or is it that someone with a PhD in Philosophy states unequivocally that the vaccine will not work as intended to slow the spread. That vaccinated individuals will continue to get infected and spread the disease. AND, that we have to wait for herd immunity of 60%. Hers is a cynical point of view at a time when Thailand is exploring how to get out of this mess. By the way, John, I find your posts generally annoying and always opinionated. Would you kindly share the basis of this? What are your credentials?

          • Avatar

            Issan John

            Monday, January 25, 2021 at 10:10 pm

            My “credentials” include the ability to read and check, including reading the University of Chicago’s Faculty of Medicine brief on Dr Sirirub Changrob, which reads (unedited):

            “Siri is a postdoctoral scholar at University of Chicago pursuing a specialization in B cell response to variety type of human infectious diseases. Her current work is on development of novel immunogens and monoclonal antibodies in the context of Influenza and now more recently, human Coronavirus.”

            Given her known credentials and validated expertise at the highest level given her peer reviews I think I’ll take her “point of view” over yours.

        • Avatar


          Monday, January 25, 2021 at 3:30 pm

          IJ, I believe she rather follows the same reasoning as you do. Without a confirmative conclusion advocate that the answer is negative and will be negative till herd immunity is reached or the virus dissipates. This not a definite answer just yet. It could be well that inoculated people will not spread as is the case with vaccines for other contagious diseases.

          • Avatar

            Issan John

            Monday, January 25, 2021 at 10:47 pm

            Ray, I wouldn’t delude myself into thinking that my “reasoning” is anything like Dr Siriruk Changrob’s.

            While Bill and Billy are apparently experts who’ve conducted the same level of research over the last 12 months as her, and Marv is so dismissive that he must have done far more in depth research himself and published far more papers specifically on Covid-19 vaccinations and viral transmissions than she has (and she’s published plenty, all freely available), I’m not in their league.

            I’m guessing that Dr Siriruk Changrob’s “reasoning” is based on not just her 12 months of hands on research but a vast amount of insider knowledge from her fellow experts.

            My own “reasoning”, on the other hand, is based solely on reading what the experts say, nothing more.

            I don’t try to interpret that, I simply look at the facts they present and listen to their informed opinions.

            … and if all the leading experts agree, without exception, then my “reasoning” is that it’s odds on that they’re correct even if two or three uninformed a-holes on the internet with zero knowledge and less intelligence disagree.

            My conclusions, unsurprisingly, are the same as hers since hers are the same as all the other leading researchers and experts and I’ve merely copied them, but I wouldn’t pretend my “reasoning” was the same.

      • Avatar


        Monday, January 25, 2021 at 3:19 pm

        The majority of other vaccines stop spreading. With a new vaccine, no producer or expert on the matter will confirm anything till the data after mass inoculation is evaluated. There is just no publication just yet. But people with authority who are directly involved with inoculations have mentioned in interviews that everything at the moment points in the direction that vaccinated persons will stop spreading. When asked if this is confirmed they answered: no we need more time. Bear in mind that it also takes two injections and some weeks to reach immunity.
        I also like to point out that government representatives in the West have made statements about the efficacy and approval of the vaccines before this actually was published. There is so much at stake here that you can be sure that there are a lot of direct lines between producers and experts who advise governments. These people are in general optimistic.

      • Avatar

        Sam Charles

        Wednesday, January 27, 2021 at 1:37 pm

        totally agree with you Ben

  3. Avatar


    Sunday, January 24, 2021 at 9:02 pm

    «une légère fièvre, des maux de tête, des douleurs musculaires et des frissons»
    During how many hours, days?

  4. Avatar


    Monday, January 25, 2021 at 12:20 am

    She is not a “medical doctor.” “A postdoctoral researcher or postdoc is a person professionally conducting research after the completion of their doctoral studies (typically a PhD).” That she had the vaccine hardly makes her qualified to proclaim that a vaccinated person can get and spread the disease until “60% of the population, or the virus dissipates.” If the efficacy of the vaccine is anything under 100%, a vaccinated person could get and spread the virus, but the rate of the spread and the impact on hospitals as well as the mortality rate will be diminished considerably. This will be enough for life to mostly return to normal. That she is Thai is irrelevant. This is a stupid article and hardly newsworthy.

    • Avatar

      Udo haarkötter

      Monday, January 25, 2021 at 8:30 am

      Das ist sehr schlecht wiedergegeben worden,leider,nicht wie im orginal geschrieben,also schon mist,daher nur ein Kommentar von mir

    • Avatar

      Issan John

      Monday, January 25, 2021 at 11:13 am

      Ben, in case you haven’t checked who Dr Sriruk Changrob is, as Bill and Marv obviously hadn’t before they decided to disagree with her, she’s a pre-eminent researcher in virology and vaccines who’s spent the last year with a team from the University of Chicago studying Covid-19 and publishing a number of highly respected, widely cited and peer reviewed papers on the virus, its transmission, and vaccines.

      Their papers are all easily available on line.

      On the other hand, Bill, Marv, and now Billy are … well … not.

      • Avatar


        Tuesday, January 26, 2021 at 4:34 am

        If she is quoted correctly I must agree she doesn’t say anything wrong. It is just that some here state that inoculated persons will still be contagious after they have reached immunity. Yes, inoculated people can still spread the virus. However, Siriruk doesn’t give a time span. At some point this could stop. We don’t know yet, but it will not be extraordinary if this will be confirmed. And yes, an inoculated person still need to practice social distancing and wear a mask even if the virus cannot multiply in his or her body. The virus could still be present on the skin if a contaminated surface has been touched.

  5. Avatar

    Issan John

    Monday, January 25, 2021 at 1:15 am

    Marv, I think that if you look at what she’s researching it’s very clear why she may have been “moved to the front of the line”.

    … that’s why I’m wondering why you and Bill disagree with her so strongly as this is very clearly her particular field of research and expertise.

    Her research papers into Covid-19 and the vaccines over the last year are readily available, widely cited and peer reviewed, which is why I’m wondering why you think she’s so misinformed …..

  6. Avatar


    Monday, January 25, 2021 at 8:22 am

    In Deutschland bekommen wir gerade die Impfung,zuerst die älteren und und medizinisches Personal,dann muss man beide Impfungen haben und soll geschützt sein,ob eine Verbreiterung dann noch möglich ist weiß man noch nicht genau,eine Nebenwirkungen ist möglich wie bei allen Impfstoffen muss aber nicht sein,fast alle kommen gut klar damit zur Zeit und ein paar Kollateralschäden gibts immer,ich würde mir nicht in die Hose machen vor Angst,warte selber darauf das ich sie endlich bekomme,und wenn Thailand noch nichts bestellt hat bis jetzt wird es eh dauern,da sie schon Lieferschwierigkeiten für Europa haben,man ist mit der Herstellung nicht schnell genug,eine etwas über 94 prozentige Sicherheit wurde angegeben was ja schon mal etwas ist,sich mit Maske schützen sollte man weiterhin

  7. Avatar


    Monday, January 25, 2021 at 9:28 am

    A true trail blazer from Thai.

  8. Avatar

    Issan John

    Monday, January 25, 2021 at 12:07 pm

    Her research certainly makes her a “trail blazer” and worthy of a considerable amount of respect.

    I actually found all this seriously amusing, if a bit sad, as it somehow sums up so much about so many commenting here.

    Neither the original article nor the Thaiger mentioned what she was researching, so without a second’s thought Bill, Marv and Billy happily trashed the article because she’s “Thai” so “misinformed” and “irrelevant”, making it “a stupid article and hardly newsworthy”.

    The reality, though, is that not only is everything she says supported by all other research and studies, as Ben so rightly said, and it key to when and how borders should be opened, but she herself is a leading, widely cited and peer reviewed expert.


  9. Avatar


    Monday, January 25, 2021 at 4:14 pm

    Siriruk says a person who is inoculated with the vaccine can still become infected and should continue to practice social distancing and wearing a mask until a herd immunity is developed by 60% of the population, or the virus dissipates.
    I understand that is also the stance from the Thai government and they want to keep quarantine on arrival a requirement. I just have difficulty to believe that Sirisuk, as a Thai national, would say anything different. Western experts are more optimistic.

    • Avatar

      Issan John

      Monday, January 25, 2021 at 11:57 pm

      Two problems there, Ray.

      The first is your claim that “The majority of other vaccines stop spreading.”

      As I’ve said before, this isn’t my field at all so I did a simple search for “do vaccinations stop viruses spreading” to see what the experts say.

      It was very clear that while some such as the smallpox and measles vaccines give “sterile immunity” many others such as hepatitis, whooping cough and rotavirus don’t. Some even vary depending on the vaccine, such as polio and flu vaccines.

      Looking at the US CDC, British Society for Immunology, the WHO, and half a dozen private (non-governmental) expert sites, their view was unanimous that “while sterilising immunity is often the ultimate goal of vaccine design, it is rarely achieved”.

      So, sorry, but unless they’re all wrong, the whole basis of your argument is flawed; it’s a myth. All the experts agree that the majority of other vaccines DON’T stop viruses spreading.

      The second is your claim that “Western experts are more optimistic”. I realise it’s tedious, but name any – any genuine experts in virology who’ve said that it’s probable rather than just possible.

      Not “government representatives”, but any independent genuine virology experts.

      … and a third point, but it’s only an observation.

      It’s a pleasant change to discuss something rationally here without any flaming and abuse, but I can’t help but be disappointed that you sideline Dr Sirisuk’s view with “I just have difficulty to believe that Sirisuk, as a Thai national, would say anything different [to the Thai government stance]” but you then immediately follow that with “Western experts are more optimistic” as if the “Western experts” are automatically and inevitably more independent, trustworthy and believable than their Thai counterparts.

      Having seen some “Western experts” squirming to avoid the question and say anything that doesn’t follow the party line when they obviously disagree with it completely, that’s all too evidently far from always the case.

      • Avatar


        Thursday, January 28, 2021 at 6:13 pm

        There is a good Q&A video with dr.Fauci on this subject today (28 jan) on CNN. Just search for ” could post-vaccine life mean we can go back to normal?”.

  10. Avatar

    James R

    Tuesday, January 26, 2021 at 4:56 am

    My son has had his vaccination here in the UK, no problem, other medical people he knows have had theirs with no problem.

    I think one doctor had a flu like fever but then again he could have had the flu.

    So all in all it seems fine, much better than getting the virus.

    Of course they still have to follow the virus rules just like everyone else.

    I think six million so far have had their first infection here in the UK and all seems fine.

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