1.A case of severe hookworm infection.
Linghui MA ; Dibo NOUHOUM ; Wanni WANG ; Zhishan ZHANG ; Xunya HOU ; Xinling YU ; Weicheng DENG ; Jie GUAN ; Shuaiqin HUANG ; Xiang WU
Journal of Central South University(Medical Sciences) 2022;47(6):814-822
With the improvement of sanitation, the infection rate of hookworm is greatly reduced and the severe infected case is rarely reported. Combined morphological and molecular biological examinations, a severe hookworm infection patient was diagnosed in Department of Laboratorial Examination, Quanzhou First Affiliated Hospital of Fujian Medical University. The morphological methods such as direct fecal smear microscopy, saturated brine flotation and hookworm larvae culture methods were used to identify the eggs and larvae from stool samples of the patient. There were a large number of hookworm eggs in patient's stool samples, and the average count was 60 840 per gram by modified Kato method, which belonged to severe hookworm infection. Meanwhile, to distinguish the hookworm species, the semi-nested RT-PCR assay was employed to detect hookworm internal transcribed spacer series from eggs in patient's stool samples, and the result showed that the hookworm species was confirmed to be Necator americanus.
Ancylostomatoidea/genetics*
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Animals
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Feces
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Hookworm Infections/diagnosis*
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Humans
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Necator americanus/genetics*
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Polymerase Chain Reaction
2.Application of a real-time PCR method for detecting and monitoring hookworm Necator americanus infections in Southern China.
Jia-Xu WANG ; Cang-Sang PAN ; Li-Wang CUI
Asian Pacific Journal of Tropical Biomedicine 2012;2(12):925-929
OBJECTIVETo develop a quantitative PCR method for detecting hookworm infection and quantification.
METHODSA real-time PCR method was designed based on the intergenic region II of ribosomal DNA of the hookworm Necator americanus. The detection limit of this method was compared with the microscopy-based Kato-Katz method. The real-time PCR method was used to conduct an epidemiological survey of hookworm infection in southern Fujian Province of China.
RESULTSThe real-time PCR method was specific for detecting Necator americanus infection, and was more sensitive than conventional PCR or microscopy-based method. A preliminary survey for hookworm infection in villages of Fujian Province confirmed the high prevalence of hookworm infections in the resident populations. In addition, the infection rate in women was significantly higher than that of in men.
CONCLUSIONSA real-time PCR method is designed, which has increased detection sensitivity for more accurate epidemiological studies of hookworm infections, especially when intensity of the infection needs to be considered.
Animals ; China ; epidemiology ; DNA, Helminth ; genetics ; Female ; Humans ; Male ; Microscopy ; Necator americanus ; genetics ; isolation & purification ; Necatoriasis ; diagnosis ; epidemiology ; genetics ; Nucleic Acid Amplification Techniques ; Real-Time Polymerase Chain Reaction ; Sensitivity and Specificity ; Sentinel Surveillance ; Sequence Analysis, DNA ; Sex Distribution
3.Differential diagnosis of Trichostrongylus and hookworm eggs via PCR using ITS-1 sequence.
Tai Soon YONG ; Jong Ho LEE ; Seobo SIM ; Jongweon LEE ; Duk Young MIN ; Jong Yil CHAI ; Keeseon S EOM ; Woon Mok SOHN ; Soon Hyung LEE ; Han Jong RIM
The Korean Journal of Parasitology 2007;45(1):69-74
Trichostrongylus eggs observed in cellophane-thick smears are difficult, in practice, to distinguish from hookworm eggs. In order to overcome these limitations, a molecular approach was conducted. A Trichostrongylus colubriformis adult worm was obtained from a human in Laos, which was identified morphologically. ITS-1 sequence of this worm was determined, and found to be most similar with that of T. colubriformis among the Trichostrongylus spp. reported so far. Then, this sequence was compared with those of human hookworm species, Ancylostoma duodenale and Necator americanus, and species-specific oligonucleotide primers were designed. Polymerase chain reaction (PCR) using these primers evidenced specifically amplified PCR products of Trichostrongylus sp., A. duodenale and N. americanus from the eggs of each (520 bp, 690 bp, and 870 bp, respectively). A species-specific PCR technique can be developed in order to study the epidemiology of Trichostrongylus spp. and hookworms in endemic areas.
Ancylostoma/*genetics/isolation & purification
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Ancylostomiasis/*diagnosis/parasitology
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Animals
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Base Sequence
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DNA, Intergenic/genetics
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DNA, Protozoan/genetics
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DNA, Ribosomal Spacer/genetics
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Diagnosis, Differential
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Humans
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Molecular Sequence Data
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Necator americanus/*genetics/isolation & purification
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Phylogeny
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Polymerase Chain Reaction/*methods
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Sequence Alignment
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Trichostrongylosis/*diagnosis/parasitology
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Trichostrongylus/*genetics/isolation & purification
4.Differential diagnosis of Trichostrongylus and hookworm eggs via PCR using ITS-1 sequence.
Tai Soon YONG ; Jong Ho LEE ; Seobo SIM ; Jongweon LEE ; Duk Young MIN ; Jong Yil CHAI ; Keeseon S EOM ; Woon Mok SOHN ; Soon Hyung LEE ; Han Jong RIM
The Korean Journal of Parasitology 2007;45(1):69-74
Trichostrongylus eggs observed in cellophane-thick smears are difficult, in practice, to distinguish from hookworm eggs. In order to overcome these limitations, a molecular approach was conducted. A Trichostrongylus colubriformis adult worm was obtained from a human in Laos, which was identified morphologically. ITS-1 sequence of this worm was determined, and found to be most similar with that of T. colubriformis among the Trichostrongylus spp. reported so far. Then, this sequence was compared with those of human hookworm species, Ancylostoma duodenale and Necator americanus, and species-specific oligonucleotide primers were designed. Polymerase chain reaction (PCR) using these primers evidenced specifically amplified PCR products of Trichostrongylus sp., A. duodenale and N. americanus from the eggs of each (520 bp, 690 bp, and 870 bp, respectively). A species-specific PCR technique can be developed in order to study the epidemiology of Trichostrongylus spp. and hookworms in endemic areas.
Ancylostoma/*genetics/isolation & purification
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Ancylostomiasis/*diagnosis/parasitology
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Animals
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Base Sequence
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DNA, Intergenic/genetics
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DNA, Protozoan/genetics
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DNA, Ribosomal Spacer/genetics
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Diagnosis, Differential
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Humans
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Molecular Sequence Data
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Necator americanus/*genetics/isolation & purification
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Phylogeny
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Polymerase Chain Reaction/*methods
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Sequence Alignment
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Trichostrongylosis/*diagnosis/parasitology
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Trichostrongylus/*genetics/isolation & purification
5.Molecular Detection of Ancylostoma duodenale, Ancylostoma ceylanicum, and Necator americanus in Humans in Northeastern and Southern Thailand.
Issarapong PHOSUK ; Pewpan M INTAPAN ; Tongjit THANCHOMNANG ; Oranuch SANPOOL ; Penchom JANWAN ; Porntip LAUMMAUNWAI ; Witthaya AAMNART ; Nimit MORAKOTE ; Wanchai MALEEWONG
The Korean Journal of Parasitology 2013;51(6):747-749
The 2 principal species of hookworms infecting humans are Necator americanus and Ancylostoma duodenale. Case studies on zoonotic hookworm infections with Ancylostoma ceylanicum and/or Ancylostoma caninum are known mainly from Asian countries. Of these 2 zoonotic species, only A. ceylanicum can develop to adulthood in humans. In the present study, we report a molecular-based survey of human hookworm infections present in southern and northeastern Thailand. Thirty larval hookworm samples were obtained from fecal agar plate cultures of 10 patients in northeastren Thailand and 20 in southern Thailand. Partial ITS1, 5.8S, and ITS2 regions of the ribosomal DNA genes were amplified using PCR. The amplicons were sequenced, aligned, and compared with other hookworm sequences in GenBank database. The results showed that, in Thailand, N. americanus is more prevalent than Ancylostoma spp. and is found in both study areas. Sporadic cases of A. ceylanicum and A. duodenale infection were seen in northeastern Thailand.
Ancylostoma/classification/genetics/*isolation & purification
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Ancylostomiasis/*epidemiology
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Animals
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Cluster Analysis
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DNA, Ribosomal Spacer/chemistry/genetics
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Feces/parasitology
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Humans
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Molecular Sequence Data
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Necator americanus/classification/genetics/*isolation & purification
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Necatoriasis/*epidemiology
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Phylogeny
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Polymerase Chain Reaction
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Prevalence
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RNA, Ribosomal, 5.8S/genetics
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Sequence Analysis, DNA
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Sequence Homology, Nucleic Acid
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Thailand/epidemiology