Ancylostoma duodenale PCR test for primates

Ancylostoma duodenale is commonly known as the Old World hookworm. It primarily infects humans and can infect non-human primates, but paratenic infections of dogs, cats, pigs, and hamsters have been documented.

This parasite attaches to the wall of the small intestine, especially the jejunum, where it feeds on blood, leading to hookworm disease or ancylostomiasis. A. duodenale and Necator americanus are the main causes of intestinal hookworm infections worldwide, affecting an estimated 72.5 million people, mostly in tropical and subtropical regions like Asia, Africa, and parts of the Americas.

The adult worm is small and cylindrical, with a greyish-white or pinkish color. Adult males are about 8-11 mm long, while females are about 10-13 mm long. It has a hook-like bend at the head, which is equipped with cutting plates or teeth to latch onto the intestinal mucosa. The morphology is very similar to Necator americanus; thus, it is very difficult to differentiate the two parasites morphologically.

Adult females can shed thousands of eggs per day into feces. When these eggs are passed in the environment, especially in warm, moist soil, the eggs hatch into the infective larvae. These larvae can penetrate human skin (often through bare feet), enter the bloodstream, travel to the lungs, and then migrate to the small intestine, where they mature into adults. Transmission typically occurs in areas where sanitation is poor or where people walk barefoot on contaminated soil. Infection with A. duodenale can also occur via ingestion of larvae or possibly through breast milk in rare cases. The full cycle from infection to egg production takes about 5-9 weeks.

Infections are mostly asymptomatic in light cases, but heavy infestations can cause iron-deficiency anemia due to blood loss, abdominal pain, diarrhea, and fatigue. In children, stunted growth and cognitive impairment may result. Skin entry may cause an itchy rash called "ground itch," and lung migration can lead to cough or fever. In severe cases, it can result in gastrointestinal bleeding. Prevention relies on practicing good personal hygiene, wearing shoes in endemic areas, improving sanitation, and conducting mass deworming programs.

Although microscopic examination of feces to diagnose the parasitic infection has low cost and is simple to perform, it has low sensitivity and specificity. This method is also not suitable for environmental surveillance because the concentration of eggs is usually very low and non-homogeneous in environmental samples like soil. PCR is increasingly used to replace the traditional microscopic method because PCR can provide species-specific detection with minimal sample volume, even in complex matrices where viable eggs may be scarce or degraded (Barda et al., 2020; Miswan et al., 2022).

Utilities:

Help confirm the disease causing agent
Shorten the time required to confirm a clinical diagnosis of Ancylostoma duodenale infection
Help ensure that animal groups are free of Ancylostoma duodenale
Early prevention of spread of Ancylostoma duodenale between animals
Minimize human exposure to Ancylostoma duodenale

References:
Barda B, Schindler C, Wampfler R, Ame S, Ali SM, Keiser J. Comparison of real-time PCR and the Kato-Katz method for the diagnosis of soil-transmitted helminthiasis and assessment of cure in a randomized controlled trial. BMC Microbiol. 2020 Oct 2;20(1):298.

Miswan N, Singham GV, Othman N. Advantages and Limitations of Microscopy and Molecular Detections for Diagnosis of Soil-transmitted Helminths: An Overview. Helminthologia. 2022 Dec 30;59(4):321-340.

Specimen requirement: 2 ml of feces; or rectal swab; or 10 ml of soil; or environmental swabs or swipes; or 2 ml EDTA whole blood.

Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology: Qualitative real time PCR

Normal range: Nondetected