Infections in vaccinated Americans also may be as transmissible as those in unvaccinated people, the document said, and lead more often to severe illness.
R0 is the average amount of people a person infected with an illness will pass it on to/transmit too. It's exponential by nature. Original Covid strain had an R0 between 3 and 4, Covid delta has an to R0 between 5 and 9. Chicken pox has an R0 around 10. I'm just going to illustrate an example comparing an R0 of 3 Vs one of 6, imagine this is the difference between Covid original and Covid delta.
Example of an R0 of 3 (Original Covid)
1 person infects 3 people. Now 4 people have the the virus. Now those three people infect three people each (3x3). Now 13 people have the virus. Now those 9 new hosts infect 3 people each. (9x3) Now 40 people have the virus. Now those 27 new hosts infect 3 people each (27x3). Now 121 people have the virus. Now those 81 new hosts infect 3 people each (81x3). Now 324 people have the virus. Etc, etc etc
Example of an R0 of 6. (Delta variant)
1 person infects 6 people. Now 7 people have the virus. The 6 new hosts infect 6 people each. (6x6). Now 41 people have the virus. The 36 new hosts infect 6 people each. (36x6). Now 257 people have the virus. Now those 216 hew hosts infect 6 people each (216x6). Now 1512 people have the virus. Now those 1296 new hosts infect 6 people each (1296x6). Now 9288 people have the virus.
So just a doubling of the R0 from around 3 to around 6 increases infectivity of the virus 28 times, as R0 is exponential by nature.
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R0 is the average amount of people a person infected with an illness will pass it on to/transmit too. It's exponential by nature. Original Covid strain had an R0 between 3 and 4, Covid delta has an to R0 between 5 and 9. Chicken pox has an R0 around 10. I'm just going to illustrate an example comparing an R0 of 3 Vs one of 6, imagine this is the difference between Covid original and Covid delta.
Example of an R0 of 3 (Original Covid)
1 person infects 3 people. Now 4 people have the the virus. Now those three people infect three people each (3x3). Now 13 people have the virus. Now those 9 new hosts infect 3 people each. (9x3) Now 40 people have the virus. Now those 27 new hosts infect 3 people each (27x3). Now 121 people have the virus. Now those 81 new hosts infect 3 people each (81x3). Now 324 people have the virus. Etc, etc etc
Example of an R0 of 6. (Delta variant)
1 person infects 6 people. Now 7 people have the virus. The 6 new hosts infect 6 people each. (6x6). Now 41 people have the virus. The 36 new hosts infect 6 people each. (36x6). Now 257 people have the virus. Now those 216 hew hosts infect 6 people each (216x6). Now 1512 people have the virus. Now those 1296 new hosts infect 6 people each (1296x6). Now 9288 people have the virus.
So just a doubling of the R0 from around 3 to around 6 increases infectivity of the virus 28 times, as R0 is exponential by nature.