The vaccine is now in a phase one trial; healthy adult volunteers with documented evidence of previous infection in Brazil are being given the same dose concentration on the same schedule used in the initial study. If this study is successful, the next step would be to conduct a phase two trial to assess the rate and intensity of hookworm infection among vaccinated persons. Because the Na-ASP-2 vaccine only targets the larval stage, it is critical that all subjects enrolled in the study be treated with antihelminthic drugs to eliminate adult worms prior to vaccination. Adult hookworm antigens have also been identified as potential candidates for vaccines. When adult worms attach to the intestinal mucosa of the human host, erythrocytes are ruptured in the worms digestive tract which causes the release of free hemoglobin which is subsequently degraded by a proteolytic cascade. Several of these proteins that are responsible for this proteolytic cascade are also essential for the worms nutrition and survival. Therefore, a vaccine that could induce antibodies for these antigens could interfere with the hookworms digestive pathway and impair the worms survival. Three proteins have been identified: the aspartic protease-hemoglobinase APR-1, the cysteine protease-hemoglobinase CP-2, and a glutathione S-transferase. Vaccination with APR-1 and CP-2 led to reduced host blood loss and fecal egg counts in dogs. With APR-1, vaccination even led to reduced worm burden. Research is currently stymied at the development of at least one of these antigens as a recombinant protein for testing in clinical trials.
If the fecal sample is left for a day or more under tropical conditions, the larvae will have hatched out, so eggs might no longer be evident. In such a case, it is essential to distinguish hookworms from Strongyloides larvae, as infection with the latter has more serious implications and requires different management. The larvae of the two hookworm species can also be distinguished microscopically, although this would not be done routinely, but usually for research purposes. Adult worms are rarely seen (except via endoscopy, surgery or autopsy), but if found, would allow definitive identification of the species. Classification can be performed based on the length of the buccal cavity, the space between the oral opening and the esophagus: hookworm rhabditoform larvae have long buccal cavities whereas Strongyloides rhabditoform larvae have short buccal cavities.Recent research has focused on the development of DNA-based tools for diagnosis of infection, specific identification of hookworm, and analysis of genetic variability within hookworm populations. Because hookworm eggs are often indistinguishable from other parasitic eggs, PCR assays could serve as a molecular approach for accurate diagnosis of hookworm in the feces. Prevention
The infective larvae develop and survive in an environment of damp dirt, particularly sandy and loamy soil. They cannot survive in clay or muck. The main lines of precaution are those dictated by good hygiene behaviors:

Do not defecate in the open, but rather in toilets. Do not use untreated human excreta or raw sewage as fertilizer in agriculture. Do not walk barefoot in known infected areas. Deworm pet dogs and cats.