Christian writes:

Dear TWiV team,

It’s a bright sunny day here in Germany, so the perfect time to send you a comment on your most recent TWiV episode, #737.

There are now more than 30 cases of immune-induced thrombocytopenia evaluated by the German authorities. To my knowledge, all of these are in lower age groups, so the risk in that subpopulation is both higher and clearly above background incidence for this particular kind of thrombocytopenia.

As the association is statistically significant and any causality that posits that AstraZeneca vaccination is the result of a propensity for thrombocytopenia or any confounding third variables seems implausible, it appears reasonable to characterize the incidents as vaccine-induced events.

While the condition is treatable, it is not easily recognized due to its characteristics and its low rate of incidence in the vaccinated population, and lethality is clearly high once serious manifestations of the condition, such as a stroke, appear.

In Germany, a number of clinics have decided not to recommend the AstraZeneca vaccine to their own employees after additional cases emerged in those and other clinics last week. Last Sunday, this precipitated the decision by German authorities, who were themselves already looking at data collected daily about these incidents, to no longer recommend the vaccine for people below the age of 60.

If there were no other vaccines available for people below the age of 60, then the risk-benefit relation would still clearly favor the administration of the AstraZeneca vaccine. However, as the individual risk of COVID-19 for younger people is low, there are alternative vaccines, and the build-up of population-based immunity can be achieved at the same speed by shifting AstraZeneca vaccinations to the older population and other vaccines to the younger population, the decision not to recommend the AstraZeneca vaccine for people below 60 seems perfectly reasonable to me.

Keep up the good work!



Sylvia writes:

hello TWIV team,

You will probably get lots of comments on this, but just in case, I thought drop you a note on the discussion about pulling back on the syringe prior to injection, when delivering an IM (intramuscular) shot.

I’m a paramedic and we are routinely taught to pull back on the syringe when giving an IM injection — the main reason being that a drug will be absorbed much more quickly IV than IM, so you want to make sure that you aren’t in a vein if you intended to be in a muscle. (A good example would be epinephrine, administered IM for anaphylaxis. If this was inadvertently given IV, it would be more potent and could cause some significant side effects such as tachycardia and hypertension). 

Prehospital care providers (paramedics and firefighters) in our area are now giving COVID vaccinations. We have all been taught to pull back prior to injecting the vaccine, to ensure that we aren’t in a blood vessel. I think it’s just good practice that if something is supposed to be delivered IM (whether it is a drug or a vaccine), you want to make sure you are actually giving it in the muscle.

I will also comment that it has been quite a privilege to participate in the vaccination effort. In our area, we have mobile units that travel to senior living facilities and under-served communities, as well as mass vaccination sites that can do hundreds or potentially thousands of vaccinations a day. After seeing some of the devastation of COVID over the past year, it is great to be able to play a small part in bringing the pandemic to a close. 

Sylvia Feder

Paramedic, King County Medic One

Denis writes:

Hello All,

We’ve been watching TWIV for the past year in Abu Dhabi. We recently returned to NY following my retirement. In Abu Dhabi we received the two Sinopharm doses, the second one over six weeks ago. The question is whether we should sign up one for of the US vaccines? I’m 68 and my wife is 74. We received negative PCR results last Saturday, after being tested four days after arriving back in NY.

Any suggestion would be greatly appreciated.



Gary writes:

Dear guardians of the TWIV-o-verse,

Before I issue my rant against Pfizer’s “FACTSHEET FOR RECIPIENTS AND CAREGIVERS” (, please accept my thanks for the hours and hours of fact filled fun you’ve provided to your huge following.  I am a retired pediatrician and feel it a duty to spread the word of your existence.  Kudos!!!

Okay, to my rant: my sister-in-law was finally offered her turn to receive the Pfizer vaccine. As she waited for the injection, she was handed Pfizer’s vaccine “factsheet,” which she only later read in detail. She came away with the impression that this was an entirely experimental vaccine, that she may end up with Covid disease despite the vaccine, and that there really wasn’t much benefit in her having submitted her arm to the injection. 

My wife spoke with me about her disappointed sister’s experience, which drove me to action –  reassuring her of the safety records of the various vaccines and the enormous success they have had… rendering recipients 100% protected against severe disease, meaning hospitalization and/or death, which by any definition is success!  

This kind of CYA handout undermines public confidence in vaccines and is obviously counter-productive.  I hope you’ll read this letter to your audience and that it will get the word out that at least one vaccine manufacturer has a few legal department CYA dead-heads that are injuring the public and effectively adding ammunition to the naysayers.  Who knows, maybe we can get a more realistic and encouraging rewrite! 

Again, many thanks for your good work.


Anthony writes:

Where’s Hoffa buried? (DDD: the pigs ate him or he was cremated)

Sad to relate, the zero temperature mentioned is the Fahrenheit scale.


# # #

Some years back, I owned an International Harvester utility vehicle (the missing link to the SUV) that I used for my bird seed delivery business. A thumping sound from the shaft let me know that the universal joint was soon to fail. At a local junk yard, I spotted a likely prospect for a transplant. But, someone had already removed the wheels. With the vehicle flat on the ground, there was no way for me to get underneath to remove the shaft.

I asked an employee at the junkyard to lift up the wreck with the yard’s high-low.

“No can do. The high-low got stuck in the dirt yesterday.”

I looked down at the ground of the junkyard. Generations of oil and broken glass had mixed with the earth to form a solid asphalt-like surface. Plus, the temperature had been freezing for weeks — actually around zero some nights. I stamped my foot.

“Jose, this ground’s hard as a rock. How’d the wheels of the high-low ever sink in?”

“Here, follow me and see for yourself.”

I went with Jose along a maze-like path through the stacks of junk cars. Soon we found the high-low, teetering over to one side.

“I can’t figure it. Day after day I go by here no problem. Now look what happened this morning.”

A neat six foot by two foot section of ground had given way and dropped down maybe a foot. Two wheels of the high-low were hanging over this little precipice, unable to gain traction.

Jose continued to explain, “I wait for the boss. When he gets back, he can tell me what he wants to do now.”

“Jose, don’t show this to anybody else. Hoffa might be down there!” 

Juan writes:

Dear TWIV team, 

Please, allow me to shed some light on some issue about Colombian vaccination that came up on epidsode 734 by a distressed fellow Colombian citizen living in the Netherlands concerned about his/her grandma. I want to start by stating that certainly Colombia is not an exemption for corruption and a country with many critical ethical issues at various levels. Several scientists/physicians/health workers, myself included are very harsh critics of most of the public policies in health and other areas in this country. However it is fair to say that our society has been guided by a government that has asked for and heard the advice of health experts and has made efforts to unite the whole population around the idea of providing COVID-19 vaccination as a inalienable right for all citizens and legal or illegal residents. In that sense the presidency and the ministry of health have issued, passed and implemented an emergency law for Covid-19 vaccination. As of today, a national vaccination plan for Covid has delivered 1.182.000 doses of which 54.500 are second doses in a campaign that started on February 17. Vaccination phase 1 encompasses 100% of health workers and allied personnel and all citizens age +80. All those people make 1.7 million of a roughly 50 million nation. So, for a 4 week period of time this is surely slow but this is the best we can afford in concordance to our resources: we do not have unlimited and prompt access to vaccines that are obtained at much higher comparable costs that those for other countries in terms of Health budget related to per capita GDP.  Our vaccination resources that were considered as an example for the latinamerican region have been put to the toughest test and despite all previsible efforts we will not reach a vaccination pace comparable to first world countries. Of course, errors have been made in the process and corruption cases have been detected. Those unfortunate cases are not the majority, those do not make the real problem with regards to Covid vaccination in this nation. I regret their occurrence as much as I regret the ill press this country has gotten, some times well deserved and many more times unjustly.  The vast majority of Colombian people are lawful, caring citizens as is the case of most nations in the world. As a physician working in a tertiary care facility I can say that those errors were scrutinized and actions had been taken. I am concerned about the aged lady from episode 734. She should have been vaccinated by now or at least, she should have been scheduled for her first dose in the following days. Either Pfizer-BioNTech or Sinovac vaccines are available for phase 1 vaccination, both contemplate a second dose. Please feel free to use my contact info to provide it to your listener in the Netherlands as someone who will guide and assist his/her granny in the process of getting her vaccine. I again thank you Dr. Racaniello and your crew for all the good work you do for so many people in distant and not so famous places like Colombia. Basic scientists educating people is remarkable. You guys have helped me to polish my rusty and outdated cardiac surgeon virology concepts since last year when our service  shut down for a few months due to lack of ICU beds; fortunately I found you guys. That has prepared me to volunteer along with many other health workers at academic hospitals in educating and training an army of vaccinators to speed up this process. With best Regards, 

Juan R Correa, MD
Cardiac Surgery Unit
Hospital Universitario San Ignacio
Pontificia Universidad Javeriana