Related by context. Frequent words. (Click for all words.) 84 influenza 82 H#N# flu 79 swine flu 79 Flu 78 H#N# 78 seasonal flu 76 H#N# virus 75 flu virus 69 mumps 69 whooping cough 67 pertussis 67 swine flu virus 66 Influenza 66 Swine Flu 65 flu vaccine 64 Swine flu 64 influenza virus 64 virus 64 bird flu 63 H#N# vaccine 63 pandemic flu 63 avian flu 63 measles 62 avian influenza 62 H#N# strain 61 swine flu vaccine 61 swine flu outbreak 61 flu vaccines 60 flu pandemic 59 pneumonia 58 vaccinations 58 rabies 58 meningitis 58 bird flu virus 58 influenza pandemic 58 vaccinated 58 West Nile virus 58 vaccination 57 influenza vaccine 57 vaccine 57 dengue 57 Tamiflu 56 pandemic 55 SARS 55 colds 55 West Nile Virus 54 West Nile 54 viral infection 54 immunizations 53 MRSA 53 infection 53 anti viral 53 H#N# bird flu 53 dengue fever 53 illness 52 Hepatitis 52 sore throat 51 bronchitis 51 hepatitis 51 TB 50 encephalitis 50 tuberculosis 50 smallpox 50 vaccines 50 Bird flu 50 allergy 50 bacterial infection 49 Lyme disease 49 vaccinate 49 infections 49 malaria 49 immunization 48 vaccinating 48 salmonella 48 chlamydia 48 cervical cancer 47 Ebola 47 hepatitis B 47 staph infection 47 HPV 47 disease 47 outbreak 47 fevers 47 infectious disease 47 polio 46 antibiotics 46 cholera 46 immunized 46 highly contagious 45 diarrhea 45 Tuberculosis 44 sexually transmitted disease 44 ailment 43 antibiotic 43 asthma 43 E. coli 43 Sars 43 illnesses 43 fever 42 SARS outbreak 42 sickness