Covid-19 Vaccines & Therapeutics Twitter Surveillance for the Week of Jan 9, 2022

There were 22,122 unique tweets. The number of tweets on a given day ranged from 2,526 on Saturday, the 15th to 5,090 on Thursday, the 13th. Ivermectin had the most tweets this week with 11,874. Remdesivir had the fewest tweets this week with 889.

Covid-19 in the news this week

  • China confirmed the first community transmission of the Omicron variant
  • In the U.S., the seven-day average of new coronavirus cases exceeded 700,000 for the first time
  • Some labs are rationing access to the limited supply of Covid-19 tests by giving priority to people with symptoms or health concerns
  • The number of patients hospitalized in the U.S. for Covid-19 reached a new high
  • The Covid-19 vaccine-or-testing rules for large privates employers was blocked by the U.S. Supreme court; the mandate remains for healthcare workers who work at facilities that participate in Medicare and Medicaid
  • A new U.S. government website will allow the public to order free at-home Covid-19 rapid tests next Wednesday
Worldwide Covid-19 new cases & deaths

worldwide Covid-19 new cases and deaths week of 2022-01-09

Daily sentiment

Net daily sentiment ranged from -25.34 for Remdesivir on Sunday the 9th to 12.31 for Pfizer vaccine on Saturday the 15th.

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.

daily sentiment for tweets discussin Covid-19 vaccines and therapeutics published between 2022-01-09 and 2022-01-15

Medical conditions from the MedDRA dictionary

Infection was the most frequently observed medical condition mentioned. Infection had the highest overall net sentiment of -0.31. Poisoning had the lowest net sentiment this week (-55.12).

medical condition count sentiment
Infection 700 -0.31
Sickness 691 -39.51
Flu 200 -30.29
Coldness, Cold 148 -1.01
Bleeding 146 -27.50
Worry 113 -23.23
Pneumonia 105 -24.29
Poisoning 97 -55.12
Fever 95 -3.27
Cancer 78 -48.35

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 673 tweets with an strong positive sentiment. The top 10 most frequent medical conditions mentioned within these tweets were (1) Infection, (2) Sickness, (3) Coldness, Cold, (4) Flu, (5) Pneumonia, (6) Coughing, Cough, (7) Fever, (8) Worry, (9) Blindness, Blind, (10) Fall. Of these terms, Coughing, Cough (n=25), Blindness, Blind (n=20), Fall (n=16) were not in the top 10 most frequent terms across all tweets.

Meddra conditions associated with positive tweets about Covid-19 vaccines and therapeutics published between 2022-01-09 and 2022-01-15

Negative tweets:

There were 1547 tweets with an strong negative sentiment. The top 10 most frequent medical conditions mentioned within these tweets were (1) Sickness, (2) Infection, (3) Flu, (4) Bleeding, (5) Poisoning, (6) Rage, (7) Cancer, (8) Pneumonia, (9) Worry, (10) Pain. Of these terms, Rage (n=63), Pain (n=36) were not in the top 10 most frequent terms across all tweets.

Meddra conditions associated with negative tweets about Covid-19 vaccines and therapeutics published between 2022-01-09 and 2022-01-15

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 “payment” within the search for “Remdesivir” had the highest overall weight. When the words are summed for each topic, Ivermectin had the highest overall weight.

words associated with positive tweets about Covid-19 vaccines and therapeutics published between 2022-01-09 and 2022-01-15

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

words associated with negative tweets about Covid-19 vaccines and therapeutics published between 2022-01-09 and 2022-01-15

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
_media I had the 3rd Moderna vaccine on Wednesday morning. I honestly have not been so sick in my life, including the two times I had Sepsis! I was healthy when I had the booster and now have a high fever, chills, tightness in my chest and a very painful cough! I’m done! moderna vaccine Chills, Coughing, Cough, Fever, Fever chills, Pain, Sepsis, Sickness
i got the pfizer vaccine but moderna booster and i was just exhausted and super achey the next day and basically laid on the couch all day. the day after i felt much better but i got rly tired by like 5 pm pfizer vaccine Exhaustion
.. my wrist, and I couldn’t twist and move my wrist, elbow, and shoulder to the full range. I’ve lived with constant pain and throbbing in my entire arm for 6 months. I’m now 48 hours from the Moderna vaccine, and when I woke up I could tell my fever had completely broke. But /2 moderna vaccine Fever, Pain
is there such a thing as delayed side effect from the Pfizer vaccine? I felt fine yesterday and now I feel feverish and have body ache and I can’t sleep <U+0001F62D> pfizer vaccine Ache, Feverish
Was anyone else’s arm incredibly sore after their 2nd Pfizer vaccine? My arm feels as sore as my foot did when I fractured it. I can barely move my upper arm without it hurting. Only my shoulder hurt last time and not nearly as much. I kept waking up all night every time I moved pfizer vaccine Fracture
I received my third dose of the Moderna vaccine for covid-19 on Tuesday. During all three doses, I felt soreness near the injection site. Beyond that, the only reaction that I had to any of the doses was a slight headache after the second dose. I’m fully vaccinated and boosted. moderna vaccine Headache
Booster update: I feel terrible,so I’m not going to work. Cold chills started last night,I have a migraine &amp; my body hurts. This is how I felt when I got my 2nd Moderna vaccine too moderna vaccine Chills, Coldness, Cold, Migraine
What vaccine did you get? I had the Moderna vaccine and booster, and was fine after the booster (other than sore arm), but everyone I know who had the Moderna booster after a different vaccine had a terrible fever.

Feel better soon!

moderna vaccine Fever
Ive been having very annoying heartburn that lasts allll day since I took the COVID Pfizer vaccine. Also digestive issues like diarrhea, burning in my stomach, chest, throat … like wtf. pfizer vaccine Burn, Diarrhea, Heartburn
‘Since I got my first Moderna vaccine I started having episodes of chest pains and fast heartbeat. Had a Holter monitor attached for 1 week and diagnosed with Supraventricular Tachycardia!!! I’m scared!!..’ Posted by moderna vaccine Chest pain, Pain
I got the same symptoms I had last week as the ones I got after getting the 3rd dose of Pfizer vaccine. I was feeling tired and sleepy all the time and I had numbness on my forehead. It takes less than 2 weeks for me to feel normal. pfizer vaccine Numbness, Sleepiness, Sleepy
I’ve had the Moderna booster vaccine yesterday &amp; now I feel fucking awful. First I was too cold and shaking <U+0001F976>Then I got an all night headache <U+0001F92F> Now I’ve got a temperature <U+0001F912>#Booster #Moderna #vaccine moderna vaccine Coldness, Cold, Headache, Shaking
Covid chronicles- Saturday Night-it hit me like a wrecking ball. Hospital trip, got monoclonal antibodies-Sunday-sleep all day, Monday-Sleep all day still unable to eat. Tuesday-feeling better but super intense metallic taste in mouth. It’s been rough all..continued <U+0001F447> monoclonal antibodies Unable to eat
_bee__ I had swollen legs and arms/hands. Been diagnosed with RA due to moderna vaccine. My hands are in such pain i can barely wash my hair or fold my daughters little shirts. My legs are swollen and itch contantly (skin stretching) dont give up, i just started treatment! moderna vaccine Itching, Pain
Did anyone get the Moderna vaccine and get Covid arm? Yes.. that’s a real thing.. apparently you can get it a week after the dose.. pretty sure I have it! Yesterday my arm swelled up by the injection site, was warm and itchy. This morning it’s still irritated and swollen <U+0001F643> moderna vaccine Irritability, Irritable, Itchy, Swelling
Here’s my small list of side effects from my 3rd shot of the Pfizer vaccine (only had a sore arm first 2 times and chestpain for 3 days)

  1. Headache
  2. Night terrors
  3. Heart beating out of my chest
  4. Fatigue
  5. Stiff arm (for 5 days now)
pfizer vaccine Fatigue, Headache, Night terrors, Stiffness
I doubt anyone will see this but did anyone else get the moderna vaccine booster and have nausea when eating for days on end? It’s now been 5 full days since I’ve gotten it and I’ve barely eaten anything in those 5 days because everything makes me nauseous. I’m running out of moderna vaccine Nausea, Nauseous
I had those the first night as well. Been having issues with tachycardia since second Pfizer vaccine. Went to the ER for it and got monoclonal antibodies. Three days of flulike symptoms, then a head cold. I wish him well. pfizer vaccine Coldness, Cold
I started taking ivermectin when my wife got bad sick with Covid 2 weeks ago. I got Covid on Tuesday and continued taking the horse wormer and I literally just had a runny nose and I had a 99.5 fever for one day. I come off quarantine tomorrow and feel fine. ivermectin Fever, Runny nose, Sickness
My co-instructor who developed myocarditis after his Moderna vaccine just left work with mild symptoms of heart attack. Entire left arm numb, strange tight feeling chest, and he’s been feeling ill a couple days. Hoping it’s just GAS moderna vaccine Gas, Heart attack, Numbness

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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  • Kun Ren and Kenton Russell (2021). formattable: Create ‘Formattable’ Data Structures. R package version 0.2.1.
  • Martijn Tennekes (2021). treemap: Treemap Visualization. R package version 2.4-3.
  • Simit Patel (2021). wordpressr: An API Wrapper for WordPress Site APIs. R package version 0.1.0.
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