The pig is a curiosity in Muslim Afghanistan, where pork and pig products are illegal because they are considered irreligious, and has been in quarantine since Sunday after visitors expressed alarm it could spread the new flu strain.
"For now the pig is under quarantine, we built it a room because of swine influenza," Aziz Gul Saqib, director of Kabul Zoo, told Reuters. "We've done this because people are worried about getting the flu."
Worldwide, more than 1,000 people have been infected with the virus, according to the World Health Organization, which also says 26 people have so far died from the strain. All but one of the deaths were in Mexico, the epicenter of the outbreak.
There are no pig farms in Afghanistan and no direct civilian flights between Kabul and Mexico.
"We understand that, but most people don't have enough knowledge. When they see the pig in the cage they get worried and think that they could get ill," Saqib said.
The pig was a gift to the zoo from China, which itself quarantined some 70 Mexicans, 26 Canadians and four Americans in the past week, but later released them.
Some visitors were not concerned about the fate of the pig and said locking it away was probably for the best.
"Influenza is quite contagious and if it passes between people and animals then there's no need for the pig to be here," zoo visitor Farzana said.
Shabby and rundown, Kabul Zoo is a far cry from zoos in the developed world, but has nevertheless come a long way since it suffered on the front line of Afghanistan's 1992-4 civil war.
Mujahideen fighters then ate the deer and rabbits and shot dead the zoo's sole elephant. Shells shattered the aquarium.
One fighter climbed into the lion enclosure but was immediately killed by Marjan, the zoo's most famous inhabitant. The man's brother returned the next day and lobbed a hand grenade at the lion leaving him toothless and blind.
The zoo now holds two lions who replaced Marjan who died of old age in 2002 as well as endangered local leopards. In all, it houses 42 species of birds and mammals and 36 types of fish and attracts up to 10,000 visitors on weekends.