16% without erythema migrans ("lyme rash") https://pubmed.ncbi.nlm.nih.gov/12543291/ https://pubmed.ncbi.nlm.nih.gov/12543291/ 80% develop EM https://www.aafp.

16% without erythema migrans ("lyme rash") https://pubmed.ncbi.nlm.nih.gov/12543291/ https://pubmed.ncbi.nlm.nih.gov/12543291/ 80% develop EM https://www.aafp.org/afp/2012/0601/p1086.html https://www.aafp.org/afp/2012/0601/p1086.html You can easily find a lot of sources in this ballpark.