TABLE 1.

Comparison of conventional and real-time PCR for detection of Angiostrongylus cantonensis in mollusks and nematode samples

Biological origin of DNA sample	Geographic origin	No. of samples tested	No. of samples positive by:
			18S rRNA-based conventional PCR	ITS1-based TaqMan PCR
Parmarion martensi	Hawaii	112	75	83
Veronicella cubensis	Hawaii	50	23a	22
Laevicaulis alte	Hawaii	5	3	4
Achatina fulica	Hawaii	6	4	5
Other/unidentified mollusks	Hawaii	16	4	5
Flatworms	Hawaii	2	2	2
Slime from infected slugs	Hawaii	13	1	1
Pomacea insularum	Louisiana	31	5	5
A. costaricensis	Brazil, Costa Rica	2	2b	0
A. vasorum	United Kingdom	2	2b	0
Other nematodesc	CDC collection	14	0	0
Total		253	121	127

^aThis number includes three samples positive by PCR but later identified as non-Angiostrongylus nematodes by DNA sequencing analysis of the amplicons (20). These three samples were negative in the real-time PCR assay.

^bThe conventional PCR detects other Angiostrongylus species besides A. cantonensis.

^cTwo stool samples containing Strongyloides worms, eight environmental samples containing unclassified free-living nematodes and one of each of the following parasitic nematodes: Dipetalonema sp., Toxocara cati, Dracunculus medinensis, and Ascaris lumbricoides.