The nurse has been charged with negligence causing death and perverting the cause of justice relating to the deaths of the two babies following measles, mumps and rubella immunisations last month.
The association's president, Solialofi Papali'i, said they were confused as to why the nurse has been arrested, and also why a second nurse, who apparently administered the vaccine, was not charged as well.
She also said that Commission of Inquiry into the matter was not complete and that the post mortem results, done by Australian experts, were not even in the country.
