As shown in Table 1, there are 37 countries with importation before the introduction of Brazil and 40 countries with importation after the introduction. But in Result part, para.1, it says, "After the introduction to Brazil in early 2015, 39 countries have experienced importation by the end of January 2016." and "Note that 39 countries which had already imported ZIKV prior to importation event in Brazil were excluded from the analysis." Why?

Also, the description of Table 1 says "In Zambia, ...Thus, the year of the acceptance of the article, 2015, was assumed as the year of importation". However, the importation year of Zambia is 2014 in Table 1 instead of 2015. Why?

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