Covid-19 Vaccines & Therapeutics Twitter Surveillance for the Week of Nov 28, 2021

There were 19,691 unique tweets. The number of tweets on a given day ranged from 2,118 on Monday, the 29th to 4,116 on Thursday, the 2nd. Pfizer vaccine had the most tweets this week with 7,453. Remdesivir had the fewest tweets this week with 883.

Covid-19 in the news this week

  • Travel rules are tightened worldwide in response to Omicron variant
  • In the U.S., pharmacies have sufficient supply of Covid-19 vaccines, but struggle to meet increasing demand due to staff shortages
Worldwide Covid-19 new cases & deaths

Daily sentiment

Net daily sentiment ranged from -44.47 for Remdesivir on Sunday the 28th to 14.86 for Hydroxychloroquine on Wednesday the 1st.

The sentiment for each tweet is scored from -1 (most negative) to +1 (most positive) using VADER sentiment analysis. Net sentiment is calculated by summing the sentiment across all tweets for a given day and/or category, then normalizing the score by the number of tweets.

Medical conditions from the MedDRA dictionary

Infection was the most frequently observed medical condition mentioned. Unable to walk had the highest overall net sentiment of -0.68. Cancer had the lowest net sentiment this week (-48.68).

medical condition count sentiment
Infection 524 -2.42
Sickness 202 -31.20
Flu 149 -28.59
Fear 85 -33.68
Cancer 80 -48.68
Worry 77 -12.47
Paralyzed 70 -0.94
Unable to walk 67 -0.68
Coldness, Cold 64 -7.39
Pneumonia 64 -8.49

MedDra is a standardized medical terminology developed by the International Council for Harmonization Cross-referencing tweets against this list is a starting point for identifying medical conditions mentioned in tweets.

Cross-referencing the MedDRA dictionary by sentiment and topic

Positive tweets:

There were 519 tweets with an strong positive sentiment. The top 10 most frequent medical conditions mentioned within these tweets were (1) Infection, (2) Sickness, (3) Fall, (4) Flu, (5) Coldness, Cold, (6) Worry, (7) Fever, (8) Pneumonia, (9) Forgetfulness, (10) Embolism. Of these terms, Fall (n=26), Fever (n=19), Forgetfulness (n=14), Embolism (n=13) were not in the top 10 most frequent terms across all tweets.

Negative tweets:

There were 952 tweets with an strong negative sentiment. The top 10 most frequent medical conditions mentioned within these tweets were (1) Infection, (2) Sickness, (3) Flu, (4) Cancer, (5) Heart attack, (6) Fear, (7) Pain, (8) Pneumonia, (9) Poisoning, (10) Confused, Confusion. Of these terms, Heart attack (n=43), Pain (n=29), Poisoning (n=28), Confused, Confusion (n=26) were not in the top 10 most frequent terms across all tweets.

Word-level analysis

The 25 most important words within positive tweets (compared to negative and neutral) tweets are shown in the treemap below. The size of each box represents the weighted score of each word. The word “rogan” within the search for “Ivermectin” had the highest overall weight. When the words are summed for each topic, Ivermectin had the highest overall weight.

The 25 most important words within negative tweets (compared to positive and neutral) tweets are shown in the treemap below. The word “die” within the search for “Pfizer vaccine” had the highest overall weight. When the words are summed for each topic, “Pfizer vaccine” had the highest overall weight within negative tweets.

This analysis of words evaluates the stemmed version of words using the Snowball algorithm. By stemming words, words with similar meaning, such as pain, painful & pained, are grouped together as simply “pain”.

Beta: text classification

Tweets that describe adverse events/side effects (first person point of view)

tweet search topic(s) medical condition(s) mentioned
My first Pfizer vaccine caused a sore arm and a rather odd migraine 48 hours later. The second one made me feel quite fluey the following day. pfizer vaccine Migraine
_sutherland I had the J&J vaccine initially and felt like Bambi on my feet for several days, had a high temperature, and uncontrollable shivers. Pfizer booster this week. Sore arm first night with throbbing feeling. Less sore night after, and fine today. johnson and johnson vaccine High temperature, Shivers, Shivering
Shitla this moderna vaccine hits me hard. My whole body aching feeling so sick rn <U+0001F637> moderna vaccine Ache, Sickness
Exactly the same. I had flu-ish symptoms the day after my J&amp;J vaccine and my Moderna booster. Then the next day, both times, I woke up and felt just fine. johnson and johnson vaccine Flu
Anyone having any reaction with Moderna Vaccine? I had both shots 8 months ago. The arm where i got my shots is aching. Super weird… <U+0001F9D0> #mrna $mrna moderna vaccine Ache
Had J+J vaccine and felt very sick/ feverish for about 36 hours. Pfizer booster 2 weeks ago was much easier, I just felt a little warm the next day. johnson and johnson vaccine Feverish, Sickness
I got the Moderna vaccine. I had a sore arm for a few hours each time. It wasn’t painful just soreness. moderna vaccine Pain
I had a mild fever and got a sinus infection, but so far the worst symptom by far is the loss of taste and smell <U+0001F610> (I got the moderna vaccine) moderna vaccine Fever, Infection, Loss of taste, Sinus infection, Sinusitis
J&amp;J vaccine, Moderna booster. Headache and sore arm. Slightly feverish for a day, not too bad just blech. Good luck! johnson and johnson vaccine Feverish, Headache
I took the Pfizer vaccine and I felt fine after the first one but the second one made me sick for about 2 or 3 days I was out of work. But I’m not dead. pfizer vaccine Sickness
My first Pfizer vaccine – no problems, my second Pfizer vaccine was achy, my Pfizer booster, I ran a low fever, had a headache &amp; had no appetite. The next day I was fine. pfizer vaccine Fever, Headache
My first moderna vaccine was fine and breeze… The second one was ruthless; serious fever and headache.. I took it easy though. moderna vaccine Fever, Headache
Got the Pfizer booster and can confirm, I got bodied. I even got the Pfizer vaccine doses 1 and 2, and tanked those just fine. When I got the booster, I got fever, aches, and chills; and then I slept all day lmao pfizer vaccine Ache, Chills, Fever
Just got the #ModernaBooster today after original J&amp;J vaccine. Side effects. Bad headache, difficulty concentrating, and tired. Beats dying any day. johnson and johnson vaccine Headache
Had my booster on Tuesday, which was good. Felt a bit rough yesterday but back to normal now. Seems to be quite a normal reaction to the #Moderna vaccine (temperature and headache). Well worth it. #vaccinated moderna vaccine Headache
I got the Moderna vaccine, and had pretty bad symptoms after second dose that lasted only 36 hrs. Got booster yesterday and my arm is sore as hell but my other symptoms more mild than second dose (still had 102 degree fever, though). moderna vaccine Fever
Yes I have had headaches and muscle pain, but I am still glad I had this booster. #covid pfizer vaccine Headache, Muscle pain, Pain
I received the Moderna booster after getting the J&amp;J vaccine in the spring. Same side effects from both for me. A little lightheaded, headache, and about 24-30 hours of being really really tired… johnson and johnson vaccine Headache
Probably was the J&amp;J. My friend had the same reaction. Ended up in the ICU with multiple blood clots. I got the Moderna vaccine, only had a sore arm and tired/body aches the next day for just a few hours. Otherwise no problems. I am glad I am vaccinated, just lost 2 friends. <U+0001F622> moderna vaccine Ache
_G2 I had two AZ originally. Pfizer (comirnaty) three weeks ago. Arm hurt for a few days, felt a bit lethargic with a slight headache for a couple of days. Then absolutely fine. x pfizer vaccine Headache, Lethargic

This classifier was trained on a set of tweets manually reviewed and tagged. The classifier was trained using GloVe, a pretrained word embedding layer.


Webpage created in R version 4.1.0 (2021-05-18) and R Studio (Version 1.4.1717) using the following packages: plotly, kableExtra, formattable, treemap, and wordpressr.

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  • Martijn Tennekes (2021). treemap: Treemap Visualization. R package version 2.4-3.
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