There is concern over the threat of swine flu to Wellington Zoo's chimpanzees.

The capital now has 26 confirmed cases of the H1N1 virus, with the national total standing at 100.

Wellington Zoo's conservation and veterinary science manager Katja Geschke says Chimpanzees and great apes are highly susceptible to the normal influenza virus.

"We don't really know at this point around H1N1, if it infects other animals, or if it infects great apes. But I guess we have to assume, just because chimps are so close to us, that potentially a transfer would be possible."

Katja Geschke says if that were to happen they would have access to Tamiflu within hours for the animals.