In the report "Guidance for Assessment of Poliovirus Vaccination Status and Vaccination of Children Who Have Received Poliovirus Vaccine Outside the United States," on page 24, under the section "Children with documentation of poliovirus vaccination." the first paragraph should have read as follows.

This paper serves as an errata for the article “P. W. Eloe, J. Henderson, Neugebauer, Electron. Qual. Theory Differ. Equ. 2020, No. 74, 1–15.” In particular, proof authors give in that of Theorem 3.6 is incorrect, and so, alleged theorem remains a conjecture. this erratum, state prove correct theorem.