The infection of fish with zoonotic nematodes, particularly anisakid nematodes is of great interest to many researcherswho
study food safety, human or animal health orwho use themas biological tags for stock assessment
studies. Accurate examination of fish for infection with anisakid larvae is crucial inmaking accurate estimates of
their occurrence, abundance and prevalence in their fish hosts. Here we describe a newmethod of examining fish
for infection with these parasites. In 2015, a total of 261 fish were purchased from a fish market in New South
Wales, Australia. All fishwere first examined by routine visual examination for infectionwith zoonotic nematode
larvae and all data were recorded. Subsequently all internal organs were placed in a container and filled with
water and incubated in the room temperature overnight. The prevalence, mean intensity and mean abundance
of anisakids were significantly higher (p b 0.05) when the revised method of examination, i.e., combining visual
examination and overnight incubation in room temperature, was employed (63.98, 8.23 and 5.27, respectively)
compared to routine visual examination with orwithout the aid of a microscope (8.81, 3.78 and 0.33, respectively).
The proposed method is effective and has several advantages, such as: not using UV or HCl for fish examination,
allowing the examination of a larger number of fish in shorter time; larval specimens collected being
suitable for both morphological and DNA sequencing; and being simple and inexpensive. The disadvantages
would be the odour of the specimens after overnight incubation as well as not being suitable for use with frozen
fish.We suggest that results, conclusions or recommendations made in studies that claimno anisakid/ascaridoid
larvae were found in a fish should be approached carefully if it is only based on visual examination of the fish.