Covid-19 Vaccines & Therapeutics Twitter Surveillance for the Week of Nov 21, 2021

There were 16,843 unique tweets. The number of tweets on a given day ranged from 1,746 on Sunday, the 21st to 3,132 on Thursday, the 25th. Ivermectin had the most tweets this week with 7,798. Monoclonal antibodies had the fewest tweets this week with 609.

Covid-19 in the news this week

  • Protests in EU against new restrictions
  • Omicron variant announced as variant of Concern on November 26, first detected in South Africa
Worldwide Covid-19 new cases & deaths

Daily sentiment

Net daily sentiment ranged from -39.51 for Remdesivir on Tuesday the 23rd to 13.04 for Moderna vaccine on Saturday the 27th.

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. Infection had the highest overall net sentiment of -5.27. Fear had the lowest net sentiment this week (-32.22).

medical condition count sentiment
Infection 606 -5.27
Sickness 208 -27.06
Flu 125 -27.43
Nervousness, Nervous 125 -25.08
Fall 86 -19.54
Fear 74 -32.22
Worry 72 -9.65
Inflammation 67 -22.50
Blindness, Blind 65 -7.53
Pain 65 -28.22

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 437 tweets with an strong positive sentiment. The top 10 most frequent medical conditions mentioned within these tweets were (1) Infection, (2) Sickness, (3) Flu, (4) Worry, (5) Blindness, Blind, (6) Coldness, Cold, (7) Fall, (8) Pain, (9) Redness, (10) Fever. Of these terms, Coldness, Cold (n=18), Redness (n=12), Fever (n=10) were not in the top 10 most frequent terms across all tweets.

Negative tweets:

There were 1007 tweets with an strong negative sentiment. The top 10 most frequent medical conditions mentioned within these tweets were (1) Infection, (2) Sickness, (3) Nervousness, Nervous, (4) Flu, (5) Fall, (6) Pain, (7) Heart attack, (8) Inflammation, (9) Fear, (10) Worry. Of these terms, Heart attack (n=36) 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 “vector” 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.

The 25 most important words within negative tweets (compared to positive and neutral) tweets are shown in the treemap below. The word “africa” 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.

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
If anyone is having vaccine booster hesitancy, I got the Moderna vaccine and was VERY sick after the second dose. Like, haven’t been that sick since the flu, though it passed in ~24 hours.

Got my booster last night and have nothing to report past a sore arm and feeling tired.

moderna vaccine Flu, Sickness
since my pfizer vaccine my periods have been the worst ever. my cramps are unbearable and i feel extremely sick everytime… it’s a nightmare. pfizer vaccine Cramp, Nightmare, Nightmares, Sickness
_Siskind It’s half the dose of original Moderna vaccine. I had a headache and felt a little tired but overall, fine. moderna vaccine Headache
Side effects from booster with Janssen vaccine done yesterday: chills, headache, very slight fever up to now (managed with paracetamol) and agitated sleep with very vivid nightmares. johnson and johnson vaccine Agitated, Agitation, Chills, Fever, Headache, Nightmare, Nightmares
30 hours after my Pfizer booster added to my Moderna vaccine, and I had aches, chills, and fever. Went to bed, and I was fine when I woke up. moderna vaccine Ache, Chills, Fever
Just got my booster dose of the pfizer vaccine – anyone been having any side effects? I had a pretty bad fever after my second dose so I am just curious pfizer vaccine Fever
Had J&J vaccine, had a sore arm. Had Moderna booster, had a sore arm & tiredness the next day. That was it. I’m 70. johnson and johnson vaccine Tiredness
No. I had a reaction to the J&J vaccine – one night of fever chills and headache, and feeling down the next day, but that is normal. And I’m 74. johnson and johnson vaccine Chills, Feeling down, Fever, Fever chills, Headache
_MD I received my first Pfizer vaccine on 17th June 2021, 3 weeks later:

  • I was coughing (no congestion on chest or in windpipe)
  • My chest was aching
  • It was painful when inhaling. The deeper I inhaled the stronger the pain.
pfizer vaccine Ache, Coughing, Cough, Pain
I had the Moderna vaccine. within 8 hours had high fever – lasted three days. Worst was the joint inflammation. Every joint in my body felt like it was going to burst from the pressure. Hands & feet swelled. Awful! moderna vaccine Fever, Inflammation, Joint inflammation, Swelling
Okay. Noting my reactions to the Pfizer vaccine:

  1. Injection arm sore and weak for 48 hours
  2. Feverish, fatigued and miserable for 7 days
  3. Just got the booster 11 hours ago and fatigue + headache + significant arm soreness have set in.
pfizer vaccine Fatigue, Feverish, Headache, Weakness
Glad you survive COVID! I had the same delayed reaction to the Moderna vaccine on the 2nd dose. The other two I just had a sore arm except the booster 1/2 dose gave me a slight fever to 99. something. moderna vaccine Fever
I had terrible side effects that lasted a week from the second Moderna vaccine, but the booster, which I was dreading, was just a 24 hour side effect scenario – mild flu-like symptoms…. chills, low grade fever, like that….. moderna vaccine Chills, Fever, Flu, Flu-like symptoms
Got my booster shot this weekend, 8 months after my 2nd #Pfizer vaccine, just ahead of the #holidayseason & “Winter Spike”. ! Felt light shoulder pain, nothing bad! #BoosterShots pfizer vaccine Pain, Shoulder pain
I had mine on Friday, Moderna vaccine we given a choice between that and Pfizer. I am just feeling a bit better. Sore arm, headache, sickness and aching limbs… #Booster moderna vaccine Ache, Headache, Sickness
Are there others here who developed chronic hives after their second dose of moderna vaccine?I’ve been having annoying hives for a month now ever since I got my second shot

I can’t live my life itchy every night

moderna vaccine Hives, Itchy
_Siskind 2nd Moderna vaccine kicked my ass. Booster reaction was mild. Tired, slight headache and a little achy for a few hours. Nothing I couldn’t handle or function with. I’m 70. moderna vaccine Headache
Man I got the Pfizer vaccine way back and legit only got a rash as a side effect but I got the moderna booster yesterday and RIP me I guess pfizer vaccine Rash
_Siskind Got Pfizer vaccine, Moderna booster. Sore arm and painful swollen gland in armpit of shot arm. Was gone within a week. My husband had same, and felt a little “puny” for about a half day the next day, but then was gone. pfizer vaccine Pain, Swollen glands
_Siskind I had the Moderna vaccine (2x) and the booster. Couple of days of very tired and one episode of chills. Done. Definitely worth it. moderna vaccine Chills

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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