Related by context. Frequent words. (Click for all words.) 75 pandemics 64 influenza pandemic 63 flu pandemic 60 pandemic 59 epidemics 54 pandemic flu 54 flu epidemic 53 H#N# pandemic 53 influenza viruses 52 flu strains 52 pandemic influenza 52 outbreaks 51 flu viruses 51 influenza virus 50 avian flu 49 influenza 49 tsunamis 49 pandemic strain 49 swine flu pandemic 49 flu virus 48 H#N# avian influenza 47 H#N# strain 47 seasonal flu 47 seasonal influenza 47 disasters 47 earthquakes 46 H#N# swine flu 46 H#N# 46 natural catastrophes 46 H#N# influenza virus 46 bird flu outbreaks 46 bird flu 46 bird flu pandemic 46 natural disasters 45 extinctions 45 Ebola 45 avian influenza 45 smallpox 45 Avian flu 45 outbreak 45 bubonic plague 45 catastrophes 44 H#N# virus 44 infectious diseases 44 bird flu outbreak 43 quakes 43 bird flu virus 43 infectious disease 43 H#N# bird flu 43 H#N# flu 43 flu 43 recessions 43 viruses 43 mass extinction 43 cyclones 43 swine flu virus 43 epidemic 42 genocides 42 famines 42 Flu 42 antiviral drugs 41 food borne illnesses 41 hurricanes 41 calamities 41 crises 41 Severe Acute Respiratory Syndrome 41 typhoons 41 H#N# influenza 41 rotavirus 41 swine flu outbreak 41 mosquito borne disease 41 vCJD 41 temblors 41 swine flu 41 infections 40 virulent strain 40 monkeypox 40 floods 40 diseases 40 whooping cough 40 Influenza 40 Bird flu 40 pathogens 40 mutations 40 encephalitis 40 malaria parasite 39 vaccines 39 El Nino 39 Outbreaks 39 disease 39 volcanic eruptions 39 downturns 39 malaria 39 influenza vaccines 39 SARS outbreak 39 antibiotic resistance 39 tropical cyclones 39 tornadoes 39 contagious diseases 39 drug resistant strains 39 virus