Indonesia reported two outbreaks of FMD to the World Organisation for Animal Health (OIE) on May 9, after being free from it for 30 years.
Bali has about 16 million cattle, and now over 20,000 animals have been infected in 16 provinces on four Islands - Sumatra, Java, Kalimantan and Lombok.
FMD is also present in Malaysia and China.
"New Zealand has no direct flights to Bali, but MPI advises to not let overseas visitors near stock for a week after they were last near animals or infected places overseas," Langford said.
Frontline staff at the border are paying close attention to goods and any travellers arriving in the country with Indonesia as their point of departure.
"Our biosecurity defenders are doing their bit - we need you to do the same," Langford said.
"Bring back a tan - not Foot and Mouth disease."