DNA technological progress toward advanced diagnostic tools to support human hookworm control.

Blood-feeding hookworms are parasitic nematodes of major human health importance. Currently, it is estimated that 740 million people are infected worldwide, and more than 80 million of them are severely affected clinically by hookworm disease. In spite of the health problems caused and the advances toward the development of vaccines against some hookworms, limited attention has been paid to the need for improved, practical methods of diagnosis. Accurate diagnosis and genetic characterization of hookworms is central to their effective control. While traditional diagnostic methods have considerable limitations, there has been some progress toward the development of molecular-diagnostic tools. The present article provides a brief background on hookworm disease of humans, reviews the main methods that have been used for diagnosis and describes progress in establishing polymerase chain reaction (PCR)-based methods for the specific diagnosis of hookworm infection and the genetic characterisation of the causative agents. This progress provides a foundation for the rapid development of practical, highly sensitive and specific diagnostic and analytical tools to be used in improved hookworm prevention and control programmes.

First report and characterization of adult Uncinaria spp. in New Zealand Sea Lion (Phocarctos hookeri) pups from the Auckland Islands, New Zealand.

Two species of hookworms (Uncinaria lucasi and Uncinaria hamiltoni) have been formally described from pinnipeds, but dissimilar types are noted from these hosts. This report is the first description of hookworms (Uncinaria spp.) from the New Zealand sea lion, Phocarctos hookeri. The nematodes were collected from dead pups on Enderby Island (Auckland Islands, 50 degrees 30', 166 degrees 17') during January and February, 2004. Standard measurements of male and female hookworms were obtained, providing a general morphometric characterization of the hookworm species in P. hookeri. Considerable variations in the body length of adult hookworms were noted within the same host. The arrangement of some of the bursal rays differs from that described for U. lucasi and U. hamiltoni.

[Molecular and morphological comparison of hookworms from genus Uncinaria invading red fox (Vulpes vulpes) and dog (Canis familiaris)]. / Morfologiczne i molekularne porównanie nicieni z rodzaju Uncinaria pasozytujacych u lisa (Vulpes vulpes) i psa (Canis familiaris).

Two species of hookworms from genus Uncinaria have been found so far in Poland. Uncinaria stenocephala infects mainly dog, wolf and red fox, whereas Uncinaria criniformis is a parasite of mustelids (but it was also reported from red fox). 19 male and 29 female hookworms from red foxes have been compared with 10 male and 12 female worms from dogs. Hookworms from dogs were generally smaller than these from foxes, but no other morphological differences could be found. These hookworms were qualified to species Uncinaria stenocephala on the ground of morphology of male. Genomic DNA samples have been isolated from these hookworms and segments of rDNA including part of small subunit of ribosomal RNA gene; internal transcribed spacer 1 (ITS1); 5.8 S ribosomal RNA; internal transcribed spacer 2 (ITS2) and part of large subunit of ribosomal RNA have been amplified and sequenced. Sequences from Uncinaria obtained both from foxes and dogs have shown very high similarity to the sequence of Uncinaria stenocephala, so all examined hookworms have been classified as belonging to this species.

Photomicrographic images of some features of Uncinaria spp (Nematoda: Ancylostomatidae) from otariid pinnipeds.

Photomicrographs of several morphologic features of hookworms (Uncinaria spp) from northern fur seal (Callorhinus ursinus) and California sea lion (Zalophus californianus) pups are presented. The main purpose is to show and describe some physical characteristics of hookworms from the two hosts; it is not to decide from these attributes whether the Uncinaria spp are the same species. The number of species of Uncinaria in pinnipeds is uncertain and specimens need to be examined from the various infected seals and sea lions before the taxonomy of these parasites can be clarified. Information in the present paper should aid in this determination.

Ultrastructure of the adults of Bunostomium phlebotomum (Nematoda: Ancylostomatidae).

The morphology of the male and female of Bunostomum phlebotomum are described based on scanning electron microscope (SEM) observations. The attachment of the worms to the small intestinal mucosa and during the copula were observed. Structures of the buccal capsule and genital organs were also studied.

Scanning electron microscopy of Bunostomum phlebotomum (Railliet, 1900).

Live specimens of Bunostomum phlebotomum were collected from the small intestine of a calf and processed for scanning electron microscopy using standard methods. This paper describes the surface morphology of adult worms. All these hookworms showed a dorsally bent anterior end with its buccal capsule, which opens antero-dorsally with a pair of chitinous cutting plates on the ventral margin. Prominent cervical papillae and a well developed male bursa with a dorsal and 2 lateral lobes, were observed. The female tail is slender and pointed with the anal opening close to the tip. Further studies are necessary to demonstrate morphological differences from other hookworms and to obtain more detail of the male bursa and female tail.

Light microscopy and scanning electron microscopy of Bathmostomum sangeri Cobbold, 1879, of elephants.

Bathmostomum sangeri is an intestinal parasite of the elephant. Males measured 12.15-14.25 mm in length; females measured 14.98-17.68 mm in length. Buccal capsule is well-developed and funnel-shaped. There is a raised and transverse fissure ridge around the oral margin. The internal wall of the buccal capsule is raised into a series of circular ridges or lamellae. Teeth or cutting plates could not be seen. Spicules are stout, wing-like structures. The telamon is pear-shaped, but a gibernaculum is not present. There are two pairs of papillae on the either side of the cloacal opening. The female tail is gradually tepering.