=Paper= {{Paper |id=Vol-3370/paper19 |storemode=property |title=Multi-label Infectious Disease News Event Corpus |pdfUrl=https://ceur-ws.org/Vol-3370/paper19.pdf |volume=Vol-3370 |authors=Jakub Piskorski,Nicolas Stefanovitch,Brian Doherty,Jens Linge,Sopho Karazi,Jas Mantero,Guillaume Jacquet,Alessio Spadaro,Giulia Teodori |dblpUrl=https://dblp.org/rec/conf/ecir/PiskorskiSDLKMJ23 }} ==Multi-label Infectious Disease News Event Corpus== https://ceur-ws.org/Vol-3370/paper19.pdf
Multi-label Infectious Disease News Event Corpus
Jakub Piskorski1,∗ , Nicolas Stefanovitch2 , Brian Doherty2 , Jens P. Linge2 ,
Sopho Kharazi3 , Jas Mantero4 , Guillaume Jacquet2 , Alessio Spadaro2 and
Giulia Teodori2
1
  Polish Academy of Sciences, Warsaw, Poland
2
  European Commission Joint Research Centre, Ispra, Italy
3
  Piksel SRL
4
  Ending Pandemics


                                         Abstract
                                         This paper describes a new corpus consisting of circa 4.5K news snippets (multi-)labelled with fine-
                                         grained infectious disease-related event types. The paper presents the underlying event taxonomy
                                         consisting of 25 fine-grained event types grouped into 8 main categories, the process of creating the
                                         corpus, related statistics and reports on the performance of SVM- and RoBERTa transformer-based
                                         baseline models for multi-label event classification. The former model obtains macro 𝐹1 score of 0.56 and
                                         0.68 for fine- and coarse-grained classification, respectively, whereas the corresponding macro 𝐹1 scores
                                         for the latter model are 0.65 and 0.76, respectively.

                                         Keywords
                                         multi-label event classification, infectious diseases, machine learning, linguistic resources


1. Introduction
Surveillance and quick response to situations emerging from outbreaks of infectious diseases,
e.g. Covid-19, relies on comprehension of all related events, which, among others, are reported
in large amounts in news articles being published every day. Automated solutions that facilitate
extraction and classification of such events is crucial in order to leverage such sources of
information, especially for early-warning systems.
   In this paper, we describe a new corpus consisting of news snippets multi-labelled with
fine-grained infectious disease-related event types reported therein. The main drive behind
this endeavour was to create material for training and building respective ML-based models for
event detection/classification in epidemics-related online news gathered by a large-scale news
aggregation and analysis engine, and to share such a resource with the scientific community,
since, to the best of our knowledge, no similar publicly accessible event-centred corpus exists
for this specific domain. Event detection and classification constitutes a key enabling technique


In: R. Campos, A. Jorge, A. Jatowt, S. Bhatia, M. Litvak (eds.): Proceedings of the Text2Story’23 Workshop, Dublin
(Republic of Ireland), 2-April-2023
∗
    Corresponding author.
Envelope-Open jpiskorski@gmail.com (J. Piskorski); nicolas.stefanovitch@ec.europa.eu (N. Stefanovitch);
brian.doherty@ec.europa.eu (B. Doherty); jens.linge@ec.europa.eu (J. P. Linge); sopho.kharazi@ext.ec.europa.eu
(S. Kharazi); jasmantero@gmail.com (J. Mantero); guillaume.jacquet@ec.europa.eu (G. Jacquet);
alessio.spadaro@ec.europa.eu (A. Spadaro); giulia.teodori@ec.europa.eu (G. Teodori)
                                       © 2023 Copyright for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
    CEUR
    Workshop
    Proceedings
                  http://ceur-ws.org
                  ISSN 1613-0073
                                       CEUR Workshop Proceedings (CEUR-WS.org)




                                                                                                         171
to build higher-level applications, e.g. event extraction, news summarization, and narrative
understanding.
   Since the beginning of the Covid-19 pandemic, a vast amount of work on studying Covid-19-
related online media and automated analysis thereof has been reported, which mainly focused
on exploiting topic detection [1], fake news/misinformation narrative analysis [2], entity and
demographic-based analysis [3], and sentiment detection [4, 1], whereas relatively little work
on automated event detection and extraction has been published in this context.
   A corpus of 10K tweets containing public reports of Covid-19 events centered around reporting
cases, deaths, prevention measures, and cures was presented in [5]. A large hand-coded dataset
of over 13K policy measures introduced worldwide related to Covid-19, gathered among others
from online news, is presented in [6]. Other online media resources related to Covid-19 have
been listed on the CLARIN Covid-19 response web page. 1
    [7] presented a BERT-based system that extracts and classifies Covid-19 related events and
relations between them, using a semi-automatically created event taxonomy consisting of
76 event types. The event taxonomy in the aforementioned work exhibits, to some degree,
similarity with the one presented in this paper; however, no event-labelled corpora have been
released by the authors. Furthermore, our event taxonomy was not created automatically, but
emerged from a business requirement analysis by public health experts and has been designed
upfront to cover any infectious diseases, going beyond the Covid-19 pandemic. Finally, the
news snippets in our corpus are multi-label annotated.
   Related to our work, some short news text classification datasets have been published, e.g.
[8] introduce a corpus of ca. 200k news headlines labelled with 40 general news categories, and
work related to exploring ML-based models (accompanied with datasets) for the detection and
classification of natural disasters [9], financial [10] and socio-political events [11] reported in
the news, covering domains that, however, have little in common with pandemics and infectious
diseases.


2. News Snippet Event Corpus
This section describes the event taxonomy, creation of the corpus of news snippets with labels
corresponding to events referred to in these snippets, and provides some corpus statistics. We
consider an event2 , a situation (or a group thereof) that has either: occurred, is currently taking
place, or is planned or considered to happen in the future, in some place and at a certain point
in time (punctual events) or spanned/spans a time period with a start date and potential end
date. Furthermore, references to a state (of play) of a situation (an ongoing event) that has not
yet ended, statements and opinions made about it are also considered events.

2.1. Infectious Disease-related Event Taxonomy
The events are grouped into 8 main categories that revolve around: reporting on the disease
outbreak development, impact, measures, violations, research, support, communication, which

1
    https://www.clarin.eu/content/clarin-responses-covid-19
2
    Our notion of events is based on the TimeML standard specifications [12]




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     REPORTING: reporting single/multiple infection cases and deaths that occurred within a short period of time and provi-
     sion of general situation overview (in terms of people affected) spanning a longer time period.
     IMPACT: all events that are impacted by the outbreak of the infectious disease/pandemic, e.g. cancellation of events
     MEASURE: introduction and changes to legislation, restrictions and recommendations of preventive nature necessary
     to combat the disease, i.e. the number of infected/affected people and spread of the disease, roll-out of related vaccines,
     medicines and equipment.
     VIOLATION: any illegal activity, fraud, fake product discovery, unrest related to the introduced measures, and spread of
     misinformation.
     RESEARCH & DEVELOPMENT: reporting on the phenomena observed during the spread of the disease, progress on
     vaccines, medicine and relevant equipment development, and support to research and development related to diagnose or
     treat the disease.
     COMMUNICATION: high-level meetings to discuss the situation, impacts and/or introduce measures, and launch of new
     information sharing/collection instruments concerning the disease and related phenomena.
     SUPPORT: provision of financial and other type of support to the affected entities, community, economy, etc., and men-
     tions of the need or lack of such support.
     MISCELLANEOUS: any other events related (not covered above) or unrelated to infectious diseases, and non-events, i.e.
     texts not referring to any actual event nor a state of an event, e.g. descriptions of processes.


Figure 1: Coarse-grained Infectious Disease-related Event Categories.




are all further subdivided into 25 fine-grained event types that refer to specific aspects of the
main categories, e.g. Reporting is subdivided into Reporting cases and Reporting situation.
The brief description of the main event categories is provided in Figure 1, whereas the one
for the fine-grained types is provided in Annex A in Figure 6. The event definitions are to a
large extent ‘inclusive’, e.g., the Support: goods category covers not only the factual provision
of goods to the affected people, but also plans and intents to do so, and expression of the needs
of those in need to receive such support.
   The Miscellaneous category is envisaged to capture everything that does not fit anywhere
else, and is subdivided into: (a) other events that are related to the domain, but do not fall under
any other type, (b) events that are unrelated, and (c) non events, e.g., descriptions of certain
generic processes and phenomena that are neither tailored in time nor refer to any specific
event instances, although relevant for the domain though. It is important to emphasize at this
stage that, in a practical set-up, a different merging and subdivision of Miscellaneous might be
more beneficial for ML modelling purposes; however, the main drive behind this subdivision
was to explore how well the 3 different fine-grained classes can be distinguished. Furthermore,
the Miscellaneous: Other category was deemed as relevant from end-user perspective, i.e.
constituting a source of providing ‘interesting’ information.

2.2. Data Sampling
The input data for annotation was randomly sampled from news articles gathered by MEDISYS 3 ,
a large-scale health-related news aggregation engine [13] from a period that spans 2016-2021.
Apart from conventional media sources, MEDISYS also monitors news on hundreds of official
public health websites such as ministry of health and public health agency websites.

3
    https://medisys.newsbrief.eu/




                                                                173
        10n(OR(economy, economic, economies, financial, unemployment, bankrupt, bankruptcy, unemployed),
             OR(pandemic, lockdown, disease, diseases, infection, infections, infectious, virus, viruses))

Figure 2: An example of a Solr query used to target articles with specific categories, in this case the
category Impact: Economy. This query specifies that the word economy and its synonyms should be at
max. 10 tokens away from the word pandemic and related terms.




   News articles were sourced using keywords, and snippets were further extracted from them
by selecting up to max. first 4 sentences comprised within the first 500 characters of the
article4 . The rationale behind considering the initial part of news articles was the assumption
of inverted-pyramid style [14] of writing news articles, i.e. the most relevant events are placed
in the beginning and the least important ones are left toward the end. First, news articles were
randomly sourced using a list of circa 800 infectious disease names5 , e.g. Covid-19, ebola, zika,
malaria, etc., and relevant name variants and acronyms. Given that a large fraction of text
snippets acquired in this way fell under Miscellaneous in order to populate proportionally the
other classes in the taxonomy, an additional document sampling for each category was carried
out through the use of a more ‘focused’ combination of keywords (including synonyms) which
were required to be found within a specific text window anywhere in the body of a news article.
An example of such a keyword query is provided in Figure 2. This allowed to improve the
precision (i.e. ca. 50% of the fetched articles were reporting on events in the taxonomy that fall
into non-Miscellaneous categories). The potential bias that might have been introduced by the
use of specific keywords is mitigated by extracting text snippets only from the beginning of
articles, which do not necessarily contain any of the keywords of the query and instead use a
different wording to report on an event.
   In addition, circa 10% of text snippets were further manually selected from the news articles
to ensure the corpus is even more balanced.

2.3. Data Annotation
From the sampled text snippets described above, circa 4.5K were randomly selected for annota-
tion. 7 annotators were involved in this process, all of which had prior experience of annotating
news texts. 2 of the annotators have a background in NLP and computational linguistics, whereas
5 others were news analysts. Initially, circa 400 randomly selected snippets were annotated
by 5 annotators, who subsequently jointly resolved the conflicts. The main motivation behind
this part of the annotation process was to revise the event codebook comprising the event
definitions, which turned to be overlapping or incomplete to some degree. Next, the remainder
of the snippets was annotated, each by at least 2 annotators. Given the fact that annotations are
sets of labels, we have computed strict and loose Cohen’s 𝜅, where for the former an agreement
is considered only for identical label sets, whereas in the latter case, a non-empty overlap of the
label sets is considered an agreement. The average strict and loose 𝜅 for a pair of annotators are

4
    Some snippets are longer than 500 characters in order to respect sentence boundaries.
5
    This list contains diseases considered as the most common public health threats created for the MEDISYS platform
    for the purpose of retrieving relevant news articles.




                                                         174
     Amid rising vaccination rates across the European Union, the 27 EU leaders on Tuesday
     committed to collectively donate at least 100 million doses of Covid-19 vaccine to countries in need by
     the end of 2021. The bloc, which described itself in a joint statement signed off at summit.


Figure 3: An example of text snippet annotated with two labels, namely, Support: goods and Communi-
cation: meeting, with the corresponding phrases referring to the respective events underlined.




0.59 and 0.63 resp. The conflict resolution in the annotations was jointly carried out by 2 to 4
annotators.
   An example of a news snippet annotated with two event labels is provided in Figure 3. Further
examples are provided in Figure 7 in Annex A.

2.4. Data Statistics
The corpus consists of 4441 text snippets, whose average length is 412 characters. The average
number of fine- and coarse-grained labels per snippet is 1.26 and 1.19, respectively. Concerning
fine-grained labels, circa 77.1% of the snippets have only one such label assigned to them, whereas
the percentage of the snippets with 2, 3 and 4 labels are 19.65%, 2.9% and 0.34%, respectively.
The corpus is relatively well-balanced. The statistics for the coarse- and fine-grained labels
are provided in Table 1. The columns labelled with ‘Co-occurrence’ provide the percentage of
instances of the given class that are labelled with at least one other label. While this figure is
maximum 6.15% (Communication class) for the coarse-grained types, it can reach up to 20.56%
(Impact: displacement of people class) for the fine-grained types. The snippets labelled with
Miscellaneous do not co-occur with other labels by definition of the former. Figure 4 presents
the text snippet length histogram.
   Table 2 provides a list of most frequently co-occurring pairs of fine-grained event types, while
the complete event co-occurrence matrix is shown in Figure 8 in Annex A. Interestingly, the
two Reporting classes are the most co-occurring ones and co-occur most frequently together;
Measure: Authority Regulation and Impact: Health System tend to frequently co-occur with
them as well. The other Measure classes tend to co-occur with Measure: Authority Regulation.
Given the fact that Covid-19 has triggered a vast amount of news articles over the last 3 years,
a large part (more than 70%) of the snippets in the corpus are related to the Covid-19 pandemic.


3. Benchmark Models
We have evaluated two benchmark models, namely: (a) L2-regularized linear SVM 6 using the
One-vs-the-Rest strategy, with log TFIDF-weighted 3-5 character n-grams as features, using
vector normalization and 𝑐 = 0.2 resulting from parameter optimization, and (b) RoBERTA
base [15], a transformer-based model, using a batch size of 32, learning rate of 2−5 and 100
warming steps with 5 training epochs.

6
    We used the Liblinear implementation provided in Scikit-learn library: https://scikit-learn.org/




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Table 1
Corpus statistic: fine- and coarse-grained event labels. The co-occurrence statistics for the coarse-grained
types refer to the co-occurrence with other coarse-grained types.
                Event Type                            Number     Fraction   Co-occurrence

                Reporting                               1089      24.5%         3.31%

                Reporting cases                            614   13.83%        10.75%
                Reporting situation                        641   14.43%        11.23%

                Impact                                     853    19.2%         4.34%

                Impact: displacement of people             107    2.41%        20.56%
                Impact: health system                      117    2.63%        13.68%
                Impact: economy                            346    7.79%        7.23%
                Impact: events                             157    3.54%        6.37%
                Impact: other                              178    4.01%        8.99%

                Measure                                    987    22.2%         3.24%

                Measure: authority regulation              322    7.25%        16.77%
                Measure: facilities                        116    2.61%        11.21%
                Measure: travel                            137    3.08%        16.79%
                Measure: vaccine/medicine roll-out         387    8.71%        6.46%
                Measure: other                             100    2.25%        7.00%

                Violation                                  378    8.51%         3.87%

                Violation: restrictions and unrest         127    2.86%        11.81%
                Violation: fake product or fraud           121    2.72%        7.44%
                Violation: misinformation                  149    3.36%        5.37%

                R&D                                        532    12.0%          1.5%

                R&D: medicine progress                     187    4.21%         2.67%
                R&D: phenomena                             272    6.12%         2.21%
                R&D: funding                               97     2.18%         2.06%

                Communication                              358    8.06%         6.15%

                Communication: meeting                     158    5.81%         9.30%
                Communication: launch instrument           101    2.27%         4.95%

                Support                                    293     6.6%         5.80%

                Support: financial                         189    4.26%         8.47%
                Support: goods                             113    2.54%         7.08%

                Miscellaneous                              779    17.5%          0.0%

                Miscellaneous: other                       158   3.56%           0.0%
                Miscellaneous: unrelated                   508   11.44%          0.0%
                Miscellaneous: non events                  115   2.59%           0.0%



  For the purpose of evaluation of these models, we use micro, macro, weighted and samples




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Figure 4: Text Snippet Length histogram.



Table 2
Top co-occurring pairs of fine-grained event labels: (a) Count stands for the absolute number of co-
occurrences of Type 1 with Type 2; (b) Fraction 1 stands for the count normalised by the total number of
co-occurences of event Type 1; (c) Fraction 2 stands for the count normalised by the total number of
co-occurences of event Type 2.
       Event Type 1                         Event Type 2          Count   Fraction 1   Fraction 2
       Reporting cases                      Reporting situation   166.0      27.0         25.9
       Measure: Authority Regulation        Reporting situation    67.0      20.8         10.5
       Measure: Authority Regulation        Reporting cases        48.0      14.9          7.8
       Measure: Vaccine/Medicine Roll-out   Reporting situation    32.0      8.3           5.0
       Communication: Meeting               Reporting situation    31.0      12.0          4.8
       Impact: Economy                      Support: Financial     28.0      8.1          14.8
       Impact: Health system                Reporting situation    24.0      20.5          3.7
       Measure: Authority Regulation        Measure: Travel        21.0      6.5          15.3
       Impact: Economy                      Impact: Other          20.0      5.8          11.2
       Measure: Authority Regulation        Measure: Facilities    20.0      6.2          17.2



𝐹1 scores, where the latter is computed as an average of 𝐹1 scores computed for each pair of
sets of ground-truth and system-response labels for each instance in the training data. 5-fold
cross-validation was used.
   The overall results for both fine- and coarse-grained classification are provided in Table 3,
whereas the per-class performance of the benchmark models for the fine- and coarse-grained
scenarios is provided in Table 4 and 5, respectively.
   For both models, the overall performance shows little variation between the 𝐹1 measures.
The performance of RoBERTa vis-à-vis SVM is better in both the coarse- and the fine-grained
classification scenario, with improvements of up to 9 and 13 points in 𝐹1 measures, respectively.




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Table 3
𝐹1 scores for benchmark models for fine- and coarse-grained event classification.
                            Fine-grained Event Types                      Coarse-grained Event Types
       Approach     Micro     Macro    Weighted         Samples   Micro     Macro    Weighted    Samples
       SVM           0.60      0.56       0.59           0.55     0.69        0.68      0.69        0.67
       RoBERTa       0.69      0.65       0.68           0.68     0.76        0.76      0.76        0.76


 Table 4
 𝐹1 scores for benchmark models per class for the
 fine-grained event types.
  Event Type                           SVM    RoBERTa
  Reporting cases                      0.74      0.85
  Reporting situation                  0.64      0.75
  Impact: displacement of people       0.75      0.81
  Impact: health system                0.40      0.55               Table 5
  Impact: economy                      0.63      0.71               𝐹1 scores for benchmark models
  Impact: events                       0.64      0.83
  Impact: other                        0.24      0.42               for coarse-grained event types.
  Measure: authority regulation        0.43      0.45                Event Type         SVM     RoBERTa
  Measure: facilities                  0.55      0.70
                                                                     Reporting           0.80     0.85
  Measure: travel                      0.60      0.79
                                                                     Impact              0.65     0.73
  Measure: vaccine/medicine roll-out   0.67      0.64
                                                                     Measure             0.66     0.68
  Measure: other                       0.21      0.24
                                                                     Violation           0.72     0.79
  Violation: restrictions and unrest   0.54      0.71
                                                                     R&D                 0.69     0.71
  Violation: fake product or fraud     0.75      0.80
                                                                     Communication       0.63     0.78
  Violation: misinformation            0.71      0.64
                                                                     Support             0.58     0.70
  R&D: medicine progress               0.55      0.58
                                                                     Miscellaneous       0.68     0.73
  R&D: phenomena                       0.59      0.72
  R&D: funding                         0.64      0.81
  Communication: meeting               0.68      0.76
  Communication: launch instrument     0.59      0.70
  Support: financial                   0.55      0.76
  Support: goods                       0.49      0.63
  Miscellaneous: other                 0.11      0.34
  Miscellaneous: unrelated             0.70      0.50
  Miscellaneous: non events            0.48      0.78



  As regards the models’ performance on individual classes, one can observe that, for both
SVM and RoBERTa, the three worst performing classes, namely, Impact: Other, Measure: Other,
Miscellaneous: Other, have almost all an 𝐹1 < 0.45, and reduce the global 𝐹1 scores. The
performance behaviour might be linked to the more open and less-focused nature of the
definition of the Other classes.
  Studying the most common confusion between labels, when both classifier and ground truth
have only one label, shows (see Figure 5) that Miscellaneous has the most false positives and
that the classes Impact, Measure and Research have more false positives than all the other classes.


4. Conclusions
This paper briefly described the creation of a new corpus consisting of circa 4.5K news snippets
(multi-)labelled with fine-grained infectious disease-related event types and reported on the




                                                         178
Figure 5: Confusion matrix for coarse-grained event types, considering only the snippets that have a
single label both in the prediction and in the ground truth.


performance of SVM- and transformer-based baseline models trained using the corpus. We
intend to enlarge the corpus in the future, in particular using snippets that cover a wider range
of diseases.
   The news event corpus, accompanied by the full-fledged Codebook and annotation guidelines
is publicly available at https://github.com/jpiskorski/infectious-diseases-events to the scientific
community for research purposes. All future extensions and updates of the corpus will be made
available under the same link.


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A. Supplementary corpus information
The definition (in a simplified form) of the fine-grained event types related to infectious diseases
is provided in Figure 6. Some examples of news snippets annotated with these labels are
provided in Figure 7. Figure 8 presents event type co-occurrence matrix.




                                                180
  Reporting cases: reporting on cases of infections, hospitalizations, deaths, recoveries of single persons and groups, pro-
  vision of updates thereon, which covers a short time span and specific location.
  Reporting situation: provision of updates on the overall situation of the outbreak, current total figures, observed trends,
  forecast, which spans longer period of time, and also covers cross-regional and cross-country comparisons.
  Impact: Displacement of people: reporting on movement of persons/groups that were either forced, obliged or vol-
  untarily fled or left their homes of places of habitual residence as a consequence of the spread of the infectious disease
  and/or introduction of measures to combat the disease. Bringing back displaced people to the place of origin falls under
  this category as well.
  Impact: Health system: covers events related to the impact the disease has on the health-care system, e.g. deployment
  of additional staff, shortage of medical equipment, high bed occupancy rate, establishment of new facilities, etc.
  Impact: Economy: covers events related to impact on the economy, e.g., decline/growth of certain sectors, reducing/in-
  creasing production, gains/losses, unveiling studies on the analysis and prognosis of the economic situation.
  Impact: Events: reporting on cancellation, postponement, and changing of modi operandi in the context of political,
  sport, cultural and other mass events, etc.
  Impact: Other: reporting on other impacts of the disease, e.g., societal phenomena, political situation, future predictions,
  etc.
  Measure: Authority Regulation/Recommendation: covers events related to the introduction of measures like, e.g.
  law, formal regulations, restrictions, and recommendations by competent government authorities and international bodies
  which are specifically put in place to decrease the number of infected/affected people and thwart further spread of the
  disease.
  Measure: Facilities: covers closures of facilities (e.g. schools, universities, museums, parks) resulting from regulations
  and/or situations, re-openings, changing related modi operandi, e.g. the introduction of teleworking, etc.
  Measure: Travel: introduction of travel restrictions, recommendations, closure of borders, cancellation of flights, closure
  of airports, provision of specific transportation means to facilitate travel, etc.
  Measure: Vaccine/Medicine Roll-out: covers events revolving around the roll-out of vaccines, medicines, equipment
  to combat the disease or mitigate the consequences, and includes also events related to sharing experience, measure
  hesitancy, anti-vax movements, etc.
  Measure: Other: covers any other events related to measures, resulting from non-governmental organization decisions,
  private sector, e.g. linked to introduced laws and regulations.
  Violation: Restrictions and Unrest: covers violations against introduced laws, regulations, measures and potential
  lockdowns, and protests against the introduced laws and measures.
  Violation: Fake product or Fraud: covers events related to unveiling or warning on fake medicine or any counterfeits,
  falsified or substandard disease-related material/equipment being sold and/or distributed, and infectious disease-related
  fraud.
  Violation: Misinformation: embraces events related to revealing misinformation incidents and attempts, and issuing
  warnings about disease-related misinformation.
  Research & Development: Medicine Progress: dissemination of information and updates on the progress of research
  and development of medicines, vaccines and equipment to combat and/or protect against infectious diseases.
  Research & Development: Phenomena: reporting on research on specific phenomena observed in the context of infec-
  tious diseases and findings which might potentially contribute to the development of medicines, vaccines, etc.
  Research & Development: Funding: raising funding, launching programmes and resources for R&D of technologies
  and materials related to fight infectious diseases.
  Communication: Meeting: covers official meetings, conferences and meetings, press conferences of authorities, states,
  international organizations, task forces, experts, etc., to discuss topics related to the (outbreak of) infectious diseases and
  related topics
  Communication: Launch Instrument: reporting on new communication, information sharing and gathering instru-
  ments and methods related to infectious diseases, e.g. online platforms, databases, smartphone apps, etc.
  Support: Financial: launching, proposing and elaborating financial instruments to support affected people, organiza-
  tions, economy, etc., e.g. the introduction of changes in tax regulations to relieve the most vulnerable groups.
  Support: Goods: providing affected people with goods, materials, and services to help and alleviate the problems resulting
  from the outbreak of the disease.
  Miscellaneous: Other: is a placeholder to capture other events related to infectious diseases, which do not fall under any
  of the above categories, e.g. recruitment of new experts by a company that develops infectious disease-related vaccines.
  Miscellaneous: Unrelated: covers events that are not related to infectious diseases in any way.
  Miscellaneous: Non Events: covers texts that do not refer to any event that could be tailored to a particular point in
  time, e.g. general descriptions of processes, etc.


Figure 6: Infectious Disease-related Event Taxonomy.




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  DUBAI, United Arab Emirates Dubai’s Expo 2020 world’s fair will be postponed to Oct. 1, 2021, over the new
  coronavirus pandemic, a Paris-based body behind the events said Monday. The announcement by the Bureau
  International des Expositions came just hours after police in Kuwait dispersed what they described as a riot by
  stranded Egyptians unable to return home amid the coronavirus pandemic. The riot was the first reported sign of
  unrest from the region’s vast population of foreign workers who have lost their jobs over the crisis
  EVENTS: Impact: Events, Impact: Displacement of people, Violation: restrictions and unrest

  The World Health Organization (WHO) has confirmed the first three cases of Zika virus disease in India. Health
  Ministry officials said Sunday that the three patients in western Gujarat state had recovered. ”There is no need to
  panic,” Dr. Soumya Swaminathan, a top health ministry official, told reporters. The World Health Organization
  said in a statement released Friday that the three cases that India reported to the WHO on May 15 were detected
  through routine blood surveillance in a hospital in Ahmadabad, Gujarat’s capital”
  EVENTS: Reporting: cases

  The Gates Foundation will give Rotary $255 million, with Rotary pledging to raise $100 million, and the UK and
  Germany contributing $150 million and $130 million respectively to the global initiative. It is the second
  such grant from the foundation to Rotary International — in 2007, it gave Rotary a $100 million
  grant for a polio eradication programme, which Rotary matched dollar for dollar. The new money
  will go to vaccination programmes, better disease surveillance and research on new vaccines.
  EVENTS: Research: funding Support: financial

  Warsaw (dpa) - Czech Prime Minister Andrej Babis said on Sunday that he would like residents over
  the age of 60 to be able to register for a Covid-19 vaccination from March. The move would see the offer of vac-
  cinations extended beyond the current priority groups of health care workers, nursing home residents and staff
  and all citizens aged over 80.
  EVENTS: Measure: vaccine/medicine roll-out

  Little air cleansers are digital gadgets that are utilized to tidy up the air by decreasing or removing interior toxins
  such as germs, odours, smoke and chemicals that could be hazardous to the wellness. These small air purifier
  cleansers have different types such as the HEPA air cleanser, ozone air cleanser, or the ionic air cleanser.
  EVENTS: Miscellaneous: non event

  RAI News 24 reports that, as of January 7, Italy will go back to the colour-coded system sub-dividing Regions on the
  basis of Covid-19 restrictions. The government will decide on the colour zone for each Region on the basis of 21
  Covid-19-related criteria. However, the Regions are calling on the government to revise these criteria. Meanwhile,
  up until January 6, all of Italy will be in a red zone, meaning that bars and restaurants will stay closed
  EVENTS: Measure: authority regulation, Measure: facilities



Figure 7: Examples of text snippets annotated with event labels. The text fragments triggering the
respective events are underlined in blue.




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Figure 8: Event type co-occurrence matrix.




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