(3) 俄罗斯瑞士等33个国家 多国禁止中国月饼入境. 中国新闻网, Aug 18, 2011.
http://www.chinadaily.com.cn/dfpd/hainan/2011-08-19/content_3537513.html
(4) Traveling to the U.S. - Bringing baked goods (i.e. cakes, cookies, breads, etc). Customs and Border Protection (CBP), US Department of Homeland Security, undated.
https://help.cbp.gov/app/answers/detail/a_id/318/~/traveling-to-the-u.s.---bringing-baked-goods-(i.e.-cakes,-cookies,-breads,-etc)
(4) List of USDA-Recognized Animal Health Status of Countries/Regions Regarding Specific Livestock or Poultry Diseases, or Acceptable Commodities. Animal & Plant Health Inspection Service (APHIS), US Department of Agriculture, Jan 26, 2011.
http://www.aphis.usda.gov/import_export/animals/animal_disease_status.shtml
China is not free of
swine fever,
food-and-mouth disease (FMD),
swine vescicular disease,
Newcastle disease, or
avian influenza.
(5) Taiwan is not mentioned in the preceding "free of" list. However, it is unclear whether it is political, because Taiwan is tiny that it is overlooked.
In any event, mooncakes from Taiwan and Hong Kong (indigenous, not re-exported from Guangdong, for example) are free to mail or bring to US. HOWEVER, the mooncakes from these two will have to apply for approval in advance from US Food and Drug Administration (FDA).
Shelly Shum, Hub-Taiwan. Federal Express, October 2006.
http://www.fedex-hub.com/news/contents/pdf/2006Q3/hub_tw_en.pdf
(Home Base: Getting the moon cakes to the US on Time. Page 10)
Similarly, the mooncake from Hong Kong can come into Taiwan (by mail or in the carry-on luggage) but it has to clear Taiwan customs, which usually takes five days.
(6) List of Infectious Animal Diseases-free and infected Countries (Zones). Bureau of Animal and Plant Health Inspection and Quarantine (BAPHIQ), Council of Agriculture, Taiwan Executive Yuan 行政院 農業委員會 動植物防疫檢疫局, Apr 19, 2011 (Ref. No. Nung fang no. 1001478611).
http://www.baphiq.gov.tw/public/Attachment/14191521471.pdf
China is not on Taiwan's list, either.
What Taiwan does not allow is to bring in mooncake with meat inside. See
新聞發佈: 旅客返國切勿攜帶動植物或其產品 違禁闖關會受罰 主動丟棄沒煩惱. BAPHIQ, July 29, 2010.
http://www.baphiq.gov.tw/newsview.php?typeid=1056&menu=1054&news_id=3943