Table 2.
Topics, their classification, and key words.
| Topic | Main words | Group classification |
| Topic 1 | immune, immune_system, study, cell, system, researcher, cancer, antibody, virus, memory | Education |
| Topic 2 | child, measles, hospital, Samoa, epidemic, Sweden, people, disease, campaign, patient | World |
| Topic 3 | county, York, measles, city, orthodox, Jewish, disease, USA, Brooklyn, confirm | World |
| Topic 4 | measles, rash, symptom, fever, infection, disease, day, infect, cough, virus | Education |
| Topic 5 | vaccine, parent, autism, child, ani, polio, Wakefield, diphtheria, study, vaccinate_child | Education |
| Topic 6 | MMR, GP, December, England, measles, UK, dose_MMR, jab, HSE, NHS | Europe |
| Topic 7 | vaccination, school, federal, Spahn, measles_vaccination, Germany, day_care, measles, CDU, mandatory | Europe |
| Topic 8 | DGS, health, confirm, directorate, measles, outbreak, age, Portugal, UK, Lisbon | Europe |
| Topic 9 | hospital, measles, Italy, health, Catania, ship, vaccinate, Sicily, hospitalize, region | Europe |
| Topic 10 | country, world, Europe, organization, world_health, health_organization, European, measles, increase, Ukraine | Europe |
| Topic 11 | measles, Roma, CDC, health, dose, Greece, vaccine, population, diseases, Spain | Europe |
| Topic 12 | France, measles, health, agency, Aquitaine, epidemic, health_France, vaccinate, Poitiers, people | Europe |
| Topic 13 | obligation, dolphin, Cicciobello, decree, sport, doll, Burioni, certification, time, market | Europe |