| Keyword | CPC | PCC | Volume | Score |
|---|---|---|---|---|
| causes of the spanish flu | 0.21 | 0.9 | 218 | 20 |
| causes of the spanish flu epidemic | 1.43 | 0.3 | 2411 | 30 |
| what causes the spanish flu | 1.71 | 0.8 | 5356 | 55 |
| what were the causes of the spanish flu | 1.07 | 0.2 | 3129 | 8 |
| what type of pathogen causes spanish flu | 1.4 | 0.3 | 766 | 29 |
| known causes of the spanish flu | 0.9 | 0.6 | 9219 | 91 |
| origins of the spanish flu epidemic | 0.5 | 1 | 6690 | 24 |
| cause of spanish flu | 0.62 | 0.6 | 293 | 17 |
| what was the spanish flu caused by | 1.16 | 0.6 | 2888 | 42 |
| why did the spanish flu happen | 0.68 | 1 | 8028 | 9 |
| the spanish flu epidemic | 1.23 | 0.1 | 5089 | 2 |
| what caused the spanish influenza | 0.47 | 0.5 | 7162 | 83 |
| why did the spanish flu start | 0.18 | 0.7 | 6765 | 37 |
| how did the spanish flu began | 0.32 | 0.4 | 5921 | 30 |
| how did the spanish flu begin | 0.12 | 0.3 | 7214 | 26 |
| what virus caused the spanish flu | 1.01 | 0.3 | 4219 | 46 |
| did the spanish flu originate in spain | 0.21 | 1 | 1739 | 76 |
| what started the spanish flu | 0.97 | 1 | 3978 | 26 |
