# Exploring Pandemics Events on Twitter by Using Sentiment Analysis and Topic Modelling
## 4 Exploring Data
According to the news, on 5 March 2022, the Kenyan Ministry of Health declared an outbreak of yellow fever in the country [39]. Like malaria, Zika tends to be associated with the term mosquito. It is also associated with dengue, which is another infectious disease caused by mosquitoes. The #malaria hashtag has the highest number as well as the highest number of malaria tweets collected. Although this study does not collect tweets for the COVID-19 keyword, there are a lot of hashtags about it. It means that COVID-19 always accounts for a significant proportion of the discussion about pandemics. Apart from hashtags related to specific viruses, there are also other kinds of hashtags: #EndTigraySiege, #Mekelle, and #Ethiopia. The Tigray region is the northernmost regional state in Ethiopia. Mekelle is the capital of the Tigray region. Because of the influence of the civil war in Ethiopia [40], Tigray has been under siege for a long period. There is not enough food and medicine supply, which leaves hundreds dying daily and millions risking death. So, there are many tweets appealing that Tigray needs urgent assistance to save lives. As for #AyderReferralHospital, due to limited medical resources, there are several patients infected due to pandemics who do not receive treatment. For example, at the Ayder Referral Hospital [41], babies with meningitis and tuberculosis and a 14-year-old boy with HIV have been turned away. Figure 6 shows the number of tweets over time for different virus subsets. There are approximately 1875 relevant tweets posted each day during this period. It is interesting to compare the number of tweets with the facts in our daily life. Figure 6 shows several peaks that can be put in relation to specific events in real life, e.g., 24 March was World Tuberculosis Day and 25 April was World Malaria Day. The peak for HIV/AIDS is a little higher, i.e., 1034, on 10 March 2022, because there was National Women and Girls HIV/AIDS Awareness Day. The peak of the tuberculosis tweets was 1238 on 29 April  
Figure 5: Word cloud and bar plot for cholera. 2022. Furthermore, the 24-30 April 2022, week was World Immunization Week 2022, when people's discussion about viruses increased for tuberculosis. For other peaks, there are corresponding events: on 23 June 2022, commonwealth leaders recommitted to ending malaria; on 21 July, Gavi, the Vaccine Alliance, funded 160 million EUR to increase malaria vaccine access in Africa; on 30 August 2022, a total of 75 cases of Cholera were reported in Nepal from Kathmandu, Lalitpur, Bhaktapur, Nuwakot, and Dhading cities; and on 8 September, new phase 2b findings showed the Oxford malaria vaccine maintains a high level of protection. Figure 7 shows an earth map with the location of some tweets by considering the attribute place id, which is a unique identifier (ID) for the location on Twitter. With this ID, we have been able to obtain detailed information about the place type, the full name of this place, and the country to which it belongs. Investigating the distribution of tweets around the world is an interesting point. In this case, let us just focus on geolocated tweets by filtering out those non-geolocated observations. The total size of the original dataset is 369,472, and after filtering, our research obtains just 6863 tweets located. For malaria, most of the geolocated tweets are from Nigeria, India, Uganda, the United States (US), and Kenya. For tuberculosis, tweets from India account for the biggest proportion. For influenza and HIV/AIDS, tweets from the United States are the most frequent. As for other viruses, there is no significant pattern in distribution. Because of the limit of the size, the result is not accurate enough. In the research, just English tweets are considered. So, it is not strange that the United States always has a high proportion of data. Figure 6: The number of tweets over time for the various epidemics. Figure 7: The location of tweets related to Malaria. Figure 8 shows a distribution of the breath symptom among the 11 viruses.