INCUBATION PERIOD AND LIFE SPAN:

Incubation period: 7-8 weeks (can be as long as 30 weeks in an Indian strain).

Lifespan: A. duodenale lives 1-5 years, N. americanus can live 15-18 years (Markell 285).

MORPHOLOGY:

  • A. duodenale: Head has a slight bend in relation to body.
  • N. americanus: Head is sharply bent in relation to body.
  • Distinguishable characteristics: N. americanus’s hook is more hooked, the buccal capsule of N. americanus has only cutting plates, while A. duodenale has teeth. N. americanus’s eggs are slightly larger, 64 – 76 mm by 36 – 40 mm.

Comparision Table

 
N. americanus
A. duodenale
Buccal Cavity
dorsal and ventral cutting plates
2 ventral plates and 2 large teeth
Size of Male
7 - 9 mm
8 - 11 mm
Size of Female
9 - 11 mm
10 - 13 mm
Position of Vulva
midbody
1/3 from posterior
Egg Production
9,000/day
25,000/day
Infection via Mouth?
No
Yes
Penetration through Skin?
Yes
Yes
Longevity
15 years
5 years

Source: http://martin.parasitology.mcgill.ca/jimspage/biol/hookworm.htm

Necator americanus                                 Ancylostoma duodenale

Source: http://www.dpd.cdc.gov/DPDx/HTML/imageLibrary/Hookworm_il.htm