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PLoS Neglected Tropical Diseases Nov 2023Neglected tropical diseases (NTDs) affect most impoverished communities in developing countries, like Myanmar in Southeast Asia. NTDs have been understudied and...
BACKGROUND
Neglected tropical diseases (NTDs) affect most impoverished communities in developing countries, like Myanmar in Southeast Asia. NTDs have been understudied and underreported in Myanmar.
METHODS
A systematic review of published and grey literature (1900-2023) on neglected tropical diseases (NTDs) in Myanmar was conducted. The literature search included five international databases: PubMed, EMBASE, Ovid Global Health, and Web of Science Core Collection and one national database: the Myanmar Central Biomedical Library (locally published papers and grey literature). The selection criteria included articles with all types of study designs of current or previous infections conducted in humans, that reported NTDs, recognised by WHO, US CDC, and listed in PLoS NTDs. We included melioidosis and rickettsioses which we consider also meet the definition of an NTD.
RESULTS
A total of 5941 records were retrieved and screened, of which, 672 (11%) met the selection criteria and were included in this review. Of the included articles, 449 (65%) were published after 2000 and 369 (55%) were from two regions (Yangon and Mandalay) of Myanmar. Of the included articles, 238 (35%) reported bacterial NTDs, 212 (32%) viral NTDs, 153 (23%) helminth NTDs, 25 (4%) protozoal NTDs and 39 (6%) reported more than one aetiology. Based on reported frequency in descending order, the bacterial NTDs were leprosy, Escherichia coli enteritis, salmonellosis, cholera, shigellosis, melioidosis, leptospirosis and rickettsioses; the viral NTDs were dengue, chikungunya and Japanese encephalitis virus (JEV) infection; the protozoal NTDs were amoebiasis, giardiasis and leishmaniasis, and the helminth NTDs were ascariasis, trichuriasis, hookworm disease, filariasis and strongyloidiasis.
CONCLUSION
This review summarises NTDs reported in Myanmar over the past 100 years. The findings suggest that most NTDs are likely to be under reported, especially from the majority of the country which is far from academic centres. Research capacity building together with strengthening of laboratory systems would lead to better understanding of the true burden of NTDs in Myanmar.
TRIAL REGISTRATION
PROSPERO registration ID: CRD42018092627.
Topics: Animals; Humans; Myanmar; Melioidosis; Ascariasis; Helminths; Neglected Diseases; Tropical Medicine; Encephalitis, Japanese; Rickettsia Infections
PubMed: 37910592
DOI: 10.1371/journal.pntd.0011706 -
Parasites & Vectors Oct 2021Necator americanus is one of the major etiological agents of human ancylostomiasis. Historically, the epidemiology of ancylostomiasis in Henan Province of central China... (Review)
Review
BACKGROUND
Necator americanus is one of the major etiological agents of human ancylostomiasis. Historically, the epidemiology of ancylostomiasis in Henan Province of central China and the molecular characteristics of N. americanus have been poorly understood.
METHODS
In this study, we report a case of ancylostomiasis in Zhengzhou city of Henan Province. We also review the epidemiology of ancylostomiasis in Henan Province from 1949 to 2020. In addition, the complete mitochondrial (mt) genome of one clinical isolate is fully characterized using Illumina sequencing. All available mt genomes of hookworms in GenBank were included to reconstruct the phylogeny using both maximum likelihood (ML) and Bayesian inference (BI) methods.
RESULTS
A total of three worms were collected from the patient. These worms were identified as N. americanus based on morphological characteristics as well as confirmed by genotyping with the barcoding gene cox1. Although ancylostomiasis cases have dropped substantially in recent years, hookworm infection is still a public health problem in underdeveloped areas and remote rural areas in Henan Province. The mt genome features of the N. americanus contained 12 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and a major non-coding region. The nad1 gene showed high sequence variability among isolates, which is worth considering for future genetic studies of N. americanus. Phylogenetic analyses support the monophyly of hookworm isolates from different hosts and distinct geographical locations.
CONCLUSIONS
The mt genome of N. americanus presented here will serve as a useful data set for studying population genetics and phylogenetic relationships of hookworms. Positive measures for preventing and controlling ancylostomiasis are required by both health services and individuals in Henan Province.
Topics: Aged; Ancylostomiasis; Animals; China; DNA, Helminth; Female; Genome, Helminth; Humans; Molecular Diagnostic Techniques; Necator americanus; Necatoriasis
PubMed: 34649597
DOI: 10.1186/s13071-021-05035-3 -
Parasitology International Oct 2021Ancylostoma ceylanicum is recognized as the only zoonotic hookworm species that is able to mature into adult stage in the human intestine. While human infections caused...
Ancylostoma ceylanicum is recognized as the only zoonotic hookworm species that is able to mature into adult stage in the human intestine. While human infections caused by this hookworm species have been reported from neighboring countries and this hookworm is prevalent in dogs in Vietnam, human infection has never been reported in Vietnam. The present study, therefore, aimed to identify human infections with A. ceylanicum in Vietnam. A total of 526 fecal samples from the residents in Long An Province were collected and the presence of hookworm eggs was detected by the Kato-Katz method. The results indicated that the overall prevalence of human hookworm infection was 85/526 (16.2%). After filter paper culture, 3rd stage larvae were successfully obtained from 48 egg-positive samples. The larvae were identified for their species using semi-nested PCR-RLFP on the cox1 gene. As a result, two hookworm species were confirmed; single species infections with Necator americanus or A. ceylanicum, and mixed infections with both species were found in 47.9%, 31.3%, and 20.8% of the samples, respectively.
Topics: Ancylostoma; Ancylostomiasis; Animals; Electron Transport Complex IV; Helminth Proteins; Humans; Prevalence; Vietnam
PubMed: 34139361
DOI: 10.1016/j.parint.2021.102405 -
The Journal of Allergy and Clinical... Jul 2022Approximately 400 million individuals are infected with hookworms globally. Protective vaccines are needed to prevent reinfections, which often occur after drug...
BACKGROUND
Approximately 400 million individuals are infected with hookworms globally. Protective vaccines are needed to prevent reinfections, which often occur after drug treatment in endemic areas. Ideal vaccines are highly efficacious and well tolerated, and do not present risks to patient safety. Peptide vaccines can generate specific, highly protective responses because they focus on minimal antigenic target(s) with a specific immunoprotective mechanism. Necator americanus aspartyl protease 1 (Na-APR-1) is one of the most promising hookworm vaccine antigens. The neutralizing epitope p3 (TSLIAGPKAQVEAIQKYIGAEL), together with universal the T epitope P25 (KLIPNASLIENCTKAEL), has been used previously to produce peptide vaccines and was found to protect BALB/c mice against rodent hookworm infections, resulting in worm burden reductions of up to 98%. However, because of extensive digestion in the gastrointestinal tract, large oral vaccination doses were necessary to achieve this level of efficacy.
OBJECTIVE
We sought to overcome the limitations of oral vaccine delivery and to investigate protective efficacy and immune correlates of protection. Herein, we examined 5 different peptide vaccines following intraperitoneal injection, to compare their efficacy with that of the clinical protein antigen APR-1.
METHODS
BALB/c mice were immunized with p3-P25-based antigen that was adjuvanted with (1) lipid core peptide, (2) polymethyl methacrylate, (3) linear polyleucine, and (4) branched polyleucine (BL), or with (5) CpG/aluminum hydroxide adjuvant (alum)-adjuvanted control and protein-based (6) CpG/alum-adjuvanted Na-APR-1. The mice sera, saliva, and feces were sampled for immune response evaluation. The immunized mice were further challenged via hookworm larvae infection, and protection was evaluated by conducting intestinal hookworm counts.
RESULTS
BL and lipid core peptide generated the highest serum anti-Na-APR-1 IgG and fecal anti-APR-1 IgG titers, but only BL generated significant fecal anti-Na-APR-1 IgA titers. Upon challenge, immunization with CpG/alum-adjuvanted p3-P25, BL, and lipid core peptide provided the highest worm burden reductions of 75%, 77%, and 59%, respectively, whereas the group immunized with Na-APR-1 had only modest worm reduction of 26%. The relationships between serum anti-Na-APR-1 IgG, fecal anti-Na-APR-1 IgA and IgG, and worm burden reduction were established with R values greater than or equal to 0.9, and the crucial role of both anti-Na-APR-1 IgG and IgA responses was identified.
CONCLUSIONS
We demonstrated for the first time that p3-based vaccine candidates are safer and can deliver higher protection against hookworm infection compared with the clinical vaccine candidate, Na-APR-1.
Topics: Adjuvants, Immunologic; Aluminum Hydroxide; Animals; Epitopes; Hookworm Infections; Immunoglobulin A; Immunoglobulin G; Lipids; Mice; Mice, Inbred BALB C; Necator americanus; Vaccines, Subunit
PubMed: 35278494
DOI: 10.1016/j.jaci.2022.02.020 -
PloS One 2022In Malaysia, soil-transmitted helminth (STH) infections still persist among indigenous communities. In the past, local studies have focused mostly on epidemiologic...
In Malaysia, soil-transmitted helminth (STH) infections still persist among indigenous communities. In the past, local studies have focused mostly on epidemiologic aspects of STH infections with a scarcity of information on the efficacy of deworming treatment. The present study consisted of 2 phases: a cross-sectional phase on current epidemiological status and risk factors of STH infections and a longitudinal study over 6 weeks on triple dose albendazole efficacy against STH infections. A total of 253 participants were recruited at baseline and a pre-tested questionnaire was administered to obtain information on socio-demographics, environmental and behavioural risk factors. Stool samples were evaluated using a modified Kato-Katz technique. Cure rate (CR) and egg reduction rate (ERR) were assessed at 3 weeks following a 3-day course of 400mg albendazole treatment and infection status were observed again at 6 weeks. Baseline positivity of trichuriasis, ascariasis and hookworm infections were 56.1%, 11.9% and 20.2%, respectively. Multivariate analysis showed age below 18 years old (P = 0.004), without latrine in house (P = 0.042) and indiscriminate defecation (P = 0.032) were associated with STH infections. In the longitudinal study (N = 89), CR for trichuriasis was 64.6%, while CR of 100% was observed for both ascariasis and hookworm. ERR was above 90% for all three STH species. A rapid increased of Trichuris trichiura egg output was observed at 6 weeks. In conclusion, STH infections are highly prevalent among indigenous communities. Children and teenagers, poor sanitation and hygiene behaviour were determinants for STH infections. Triple dose albendazole is found to be efficacious against Ascaris lumbricoides and hookworm infections but has moderate curative effect with high ERR against T. trichiura. Although triple dose albendazole regimen has logistic challenges and may not be a routine option, consideration of this treatment regime may still be necessary in selective communities to reduce high intensity of T. trichiura infection.
Topics: Adolescent; Albendazole; Animals; Anthelmintics; Ascariasis; Ascaris lumbricoides; Child; Cross-Sectional Studies; Feces; Helminthiasis; Hookworm Infections; Humans; Longitudinal Studies; Soil; Trichuriasis; Trichuris
PubMed: 35960935
DOI: 10.1371/journal.pone.0272821 -
The American Journal of the Medical... Apr 2020
Topics: Adult; Albendazole; Animals; Anthelmintics; Female; Hookworm Infections; Humans; India; Iron; Treatment Outcome
PubMed: 31902519
DOI: 10.1016/j.amjms.2019.11.012 -
The American Journal of Tropical... Aug 2020We reported 865 cases of soil-transmitted nematodiasis occurring in Japan during 2000-2017. The predominant nematode was ( = 279, 32.3% of all cases), and other species...
We reported 865 cases of soil-transmitted nematodiasis occurring in Japan during 2000-2017. The predominant nematode was ( = 279, 32.3% of all cases), and other species included (30.7%), (23.1%), and spp. (13.9%). was detected primarily in patients in Okinawa and Kagoshima prefectures, which are in the south of Japan and are endemic areas for this parasitic infection, and also in about half of the prefectures of all Japan. At least 15.5 cases of strongyloidiasis occurred on average each year. The period incidence rate of strongyloidiasis cases relative to the total population of Japan was 0.012 cases per 10 person-years. The male-to-female ratio was 2.1. The average age was 75.1 ± 16.9 years, and 96.1% of patients were older than 50 years. Several reasons may explain why this previously non-endemic outside of Okinawa region, serious nematode disease is now found in much of Japan, including the increased number of transmigration and sightseeing trips in Japan, use of immunosuppressive drugs, and lack of awareness of the risks. Thus, information of strongyloidiasis and its risks must be disseminated to travelers, residents, and physicians to prevent this life-threatening parasite infection.
Topics: Adult; Aged; Aged, 80 and over; Ancylostomiasis; Animals; Ascariasis; Ascaris lumbricoides; Female; Humans; Japan; Male; Middle Aged; Strongyloides stercoralis; Strongyloidiasis; Trichuriasis; Trichuris; Young Adult
PubMed: 32588800
DOI: 10.4269/ajtmh.19-0969 -
BMC Infectious Diseases Apr 2021Malaria and helminths diseases are co-endemic in most parts of sub-Saharan Africa. Immune responses from each of these pathogens interact, and these interactions may...
BACKGROUND
Malaria and helminths diseases are co-endemic in most parts of sub-Saharan Africa. Immune responses from each of these pathogens interact, and these interactions may have implications on vaccines. The GMZ2 malaria vaccine candidate is a fusion protein of Plasmodium falciparum merozoite surface protein 3 (MSP3) and glutamate rich protein (GLURP R0). GMZ2 has recently showed modest efficacy in a phase IIb multicenter trial. Here, we assessed the effect of hookworm (Necator americanus) infection and anthelmintic treatment on naturally acquired antibody responses against GMZ2 and constituent antigens.
METHODS
This longitudinal cross-sectional study was conducted in the Kintampo North Municipality of Ghana. Blood and stool samples were taken from 158 individuals (4-88 years old) infected with either P. falciparum alone (n = 59) or both hookworm and P. falciparum (n = 63) and uninfected endemic controls (n = 36). Stool hookworm infection was detected by the Kato-Katz method and PCR. Malaria parasitaemia was detected by RDT, light microscopy and P. falciparum-specific 18S rRNA gene PCR. Serum samples were obtained prior to hookworm treatment with a single dose of albendazole (400 mg) and 3 weeks (21 days) after treatment. Levels of IgG1, IgG3 and IgM against GMZ2, MSP3 and GLURP R0 were measured by ELISA and compared among the groups, before and after treatment.
RESULTS
Participants with P. falciparum and hookworm co-infection had significantly higher IgG3 levels to GMZ2 than those with only P. falciparum infection and negative control (p < 0.05) at baseline. Treatment with albendazole led to a significant reduction in IgG3 levels against both GMZ2 and GLURP R0. Similarly, IgM and IgG1 levels against MSP3 also decreased following deworming treatment.
CONCLUSION
Individuals with co-infection had higher antibody responses to GMZ2 antigen. Treatment of hookworm/malaria co-infection resulted in a reduction in antibody responses against GMZ2 and constituent antigens after albendazole treatment. Thus, hookworm infection and treatment could have a potential implication on malaria vaccine efficacy.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Albendazole; Anthelmintics; Antibodies, Protozoan; Antigens, Protozoan; Case-Control Studies; Child; Child, Preschool; Cross-Sectional Studies; Female; Hookworm Infections; Humans; Immunoglobulin G; Longitudinal Studies; Malaria Vaccines; Malaria, Falciparum; Male; Middle Aged; Parasitemia; Protozoan Proteins; Young Adult
PubMed: 33832450
DOI: 10.1186/s12879-021-06027-5 -
Tropical Doctor Apr 2022Hookworm is one of the soil-transmitted nematodes causing anaemia and low birth weight in pregnant women. This study aimed to assess albendazole efficacy and... (Clinical Trial)
Clinical Trial
Hookworm is one of the soil-transmitted nematodes causing anaemia and low birth weight in pregnant women. This study aimed to assess albendazole efficacy and re-infection rate among pregnant women. A community-based cross-sectional study was conducted from February to September 2021 in Debre Elias District. Albendazole (400mg) was administered to assess efficacy and hookworm re-infection rate. Though the cure rate of single-dose albendazole was 81.7%, with an overall egg reduction rate of 92.5%, the re-infection rate of hookworm 18-24 weeks post-treatment was substantial at 21.4%. More effective intervention measures are thus needed.
Topics: Albendazole; Ancylostomatoidea; Animals; Anthelmintics; Cross-Sectional Studies; Ethiopia; Female; Hookworm Infections; Humans; Pregnancy; Pregnant Women; Reinfection
PubMed: 35156859
DOI: 10.1177/00494755221080593 -
Tropical Biomedicine Dec 2022Many species of helminths and protozoa caused intestinal parasitic infections (IPIs). It belongs to neglected tropical diseases (NTDs) and remains a major public health...
Many species of helminths and protozoa caused intestinal parasitic infections (IPIs). It belongs to neglected tropical diseases (NTDs) and remains a major public health problem in several Southeast Asian countries. The present study aimed to investigate the prevalence of IPIs and associated risk factors among the population in Kratie Province in northeastern Cambodia and Phnom Penh is the capital that locates in southern Cambodia. Fecal specimens (n=366) were collected in 10 villages in Kratie Province and Phnom Penh from 2019 to 2021. They were processed using the formalin ethyl-acetate concentration technique (FECT) to investigate parasites at egg and cyst stages and then examined under a light microscope. The results revealed that the prevalence of IPIs among the population in Kratie Province (n=317) and Phnom Penh (n=49) was 16.12% (n=59); of Kratie Province (n=50, 13.66%) and Phnom Penh (n=9, 2.46%), 12.02% (n=44) were helminths and 4.10% (n=15) were protozoa. The parasitic infection rate was higher in males (9.02%) than in females (7.10%) and more likely to be due to helminths (7.38%) than protozoa (1.64%). Prevalence of Opisthorchis viverrini was the highest (5.74%), followed by those of Entamoeba coli (4.10%), hookworm (3.83%), Ascaris lumbricoides (1.10%), Hymenolepis nana (1.09%), Taenia spp. (0.54%), Trichuris trichiura (0.55%), and Enterobius vermicularis (0.27%), respectively. Moreover, O. viverrini infection was the most common infection in the <20-year age group in Kratie Province. In addition, the bivariate and multivariate analyses showed that the association between gender. Gender was a significant risk factor positively associated with O. viverrini and hookworm infections (OR=0.318, 95% CI=0.122-0.8270, P=0.019 and OR=0.085, 95% CI=0.017-0.436, P=0.003, respectively). In conclusion, the IPIs were highly prevalent, especially O. viverrini and hookworm infections, among the population in Cambodia. These IPIs impact the public health burden but can be prevented by education regarding good sanitary practices in this community.
Topics: Humans; Male; Animals; Female; Cambodia; Feces; Intestinal Diseases, Parasitic; Helminths; Risk Factors; Prevalence
PubMed: 36602213
DOI: 10.47665/tb.39.4.009