50 research outputs found
Occurrence of Blastocystis in Water of Two Rivers from Recreational Areas in Malaysia
This study reports the occurrence of Blastocystis in water from two rivers, Sungai Congkak and Sungai Batu, located in recreational areas in Malaysia. This protozoan was detected in samples from both rivers with an average of 33.3% and 22.1%, respectively. It was detected highest at the downstream (73.8% and 33.8%) followed by midstream (17.5% and 25.0%) and upstream (8.8% and 7.5%) stations, with additionally higher detection during holidays (with average 47.5% and 30.8%) than week days (with average 19.2% and 13.3%), in both rivers, respectively. There was a strong association with the daily activities of locals and visitors, who came for water recreational activities, mainly located between midstream and downstream and was observed to be higher at Sungai Congkak. The detection of Blastocystis in these rivers' water implies that this protozoan could potentially be transmitted to humans by the waterborne route. Pearson correlation analysis showed that their occurrence was significantly correlated with faecal coliforms count; inconsistent correlation with dissolved oxygen, temperature and turbidity and no correlation with pH, conductivity and rainfall for both rivers. The correlation of coliforms and Blastocystis suggests the source of the Blastocystis in the water body is likely to be faecal
Drinking water is a significant predictor of Blastocystis infection among rural Malaysian primary schoolchildren
Blastocystis infection has a worldwide distribution especially among the disadvantaged population and immunocompromised subjects. This study was carried out to determine the prevalence and the association of Blastocystis infection with the socio-economic characteristics among 300 primary schoolchildren, living in rural communities in Lipis and Raub districts of Pahang state, Malaysia. Stool samples were collected and examined for the presence of Blastocystis using direct smear microscopy after in vitro cultivation in Jones' medium. The overall prevalence of Blastocystis infection was found to be as high as 25·7%. The prevalence was significantly higher among children with gastrointestinal symptoms as compared to asymptomatic children (x2=4·246; P=0·039). Univariate and multivariate analyses showed that absence of a piped water supply (OR=3·13; 95% CI=1·78, 5·46; P<0·001) and low levels of mothers’ education (OR=3·41; 95% CI=1·62, 7·18; P<0·01) were the significant predictors of Blastocystis infection. In conclusion, Blastocystis is prevalent among rural children and the important factors that determine the infection were the sources of drinking water and mothers' educational level. Interventions with provision of clean water supply and health education especially to mothers are required
Aquatic biomonitoring of Giardia cysts and Cryptosporidium oocysts in peninsular Malaysia
An aquatic biomonitoring of Giardia cysts and
Cryptosporidium oocysts in river water corresponding to
five villages situated in three states in peninsular Malaysia
was determined. There were 51.3 % (20/39) and 23.1 %
(9/39) samples positive for Giardia and Cryptosporidium
(oo)cysts, respectively. Overall mean concentration between
villages for Giardia cysts ranged from 0.10 to 25.80 cysts/l
whilst Cryptosporidium oocysts ranged from 0.10 to 0.90
oocysts/l. Detailed results of the river samples from five
villages indicated that Kuala Pangsun 100 % (9/9),
Kemensah 77.8 % (7/9), Pos Piah 33.3 % (3/9) and Paya
Lebar 33.3 % (1/3) were contaminated with Giardia cysts
whilst Cryptosporidium (oo)cysts were only detected in
Kemensah (100 %; 9/9) and Kuala Pangsun (66.6 %; 6/9).
However, the water samples from Bentong were all negative
for these waterborne parasites. Samples were collected from
lower point, midpoint and upper point. Midpoint refers to the
section of the river where the studied communities are highly
populated. Meanwhile, the position of the lower point is at
least 2 km southward of the midpoint and upper point is at
least 2 km northward of the midpoint. The highest mean
concentration for (oo)cysts was found at the lower points
[3.15±6.09 (oo)cysts/l], followed by midpoints [0.66±1.10
(oo)cysts/l] and upper points [0.66±0.92 (oo)cysts/l]. The
mean concentration of Giardia cysts was highest at Kuala
Pangsun (i.e. 5.97±7.0 cysts/l), followed by Kemensah
(0.83±0.81 cysts/l), Pos Piah (0.20±0.35 cysts/l) and Paya
Lebar (0.10±0.19 cysts/l). On the other hand, the mean
concentration of Cryptosporidium oocysts was higher at
Kemensah (0.31±0.19 cysts/l) compared to Kuala Pangsun (0.03±0.03cysts/l). All the physical and chemical parameters did not show significant correlation with both protozoa.
In future, viability status and molecular characterisation of Giardia and Cryptosporidium should be applied to identify
species and genotypes/subgenotypes for better understanding of the epidemiology of these waterborne parasites
Determination of diagnostic value of Toxoplasma gondii recombinant surface antigen (SAG1, P30) in mouse experimental model
The aim of this study was to test the potential diagnostic usefulness of recombinant Toxoplasma gondii SAG1 antigen and excretory-secretory antigen (ESA), with respect to toxoplasmosis detection and infection phase distinction in laboratory mouse by determining specifi c serum IgM and IgG antibodies with the use of indirect ELISA technique. The highest titre at the beginning of infection was demonstrated by immunoglobulin M while the highest titre at the end of the infection was displayed by immunoglobulin G. In contrast, sera of chronically infected mice, positive IgG titre was detected on day 14 p.i. for ESA or day seven p.i. with rSAG1 and increased thereafter until day 70 p.i. after which the titre stabilized. IgA antibody also showed similar kinetics as IgG. Potentially rSAG1 may be a suitable diagnostic antigen than ESA in the diagnosis of acute and chronic toxoplasmosis
Determining intestinal parasitic infections (IPIs) in inmates from Kajang Prison, Selangor, Malaysia for improved prison management
Background: The prison management in Malaysia is proactively seeking to improve the health status of the prison
inmates. Intestinal parasitic infections (IPIs) are widely distributed throughout the world and are still gaining great concern due to their significant morbidity and mortality among infected humans. In Malaysia, there is a paucity of information on IPIs among prison inmates. In order to further enhance the current health strategies employed, the present study aims to establish firm data on the prevalence and diversity of IPIs among HIV-infected and non-HIV-infected individuals in a
prison, an area in which informed knowledge is still very limited.
Methods: Samples were subjected to microscopy examination and serological test (only for Strongyloides). Speciation
for parasites on microscopy-positive samples and seropositive samples for Strongyloides were further determined via polymerase chain reaction. SPSS was used for statistical analysis. Results: A total of 294 stool and blood samples each were successfully collected, involving 131 HIV positive and 163 HIV negative adult male inmates whose age ranged from 21 to 69-years-old. Overall prevalence showed 26.5 % was positive for various IPIs. The IPIs detected included Blastocystis sp., Strongyloides stercoralis, Entamoeba spp., Cryptosporidium spp.,
Giardia spp., and Trichuris trichiura. Comparatively, the rate of IPIs was slightly higher among the HIV positive inmates (27.5 %) than HIV negative inmates (25.8 %). Interestingly, seropositivity for S. stercoralis was more predominant in HIV negative inmates (10.4 %) compared to HIV-infected inmates (6.9 %), however these findings were not statistically significant. Polymerase chain reaction (PCR) confirmed the presence of Blastocystis, Strongyloides, Entamoeba histolytica and E. dispar. Conclusions: These data will enable the health care providers and prison management staff to understand the trend and epidemiological situations in HIV/parasitic co-infections in a prison. This information will further assist in providing evidence-based guidance to improve prevention, control and management strategies of IPIs co-infections among both HIV positive and HIV negative inmates in a prison environment
Understanding Giardia infections among rural communities using the one health approach
The epidemiology of giardiasis in rural villages in Peninsular Malaysia was examined in the context of the One
Health triad that encompasses humans, animals and environment (i.e. river water). A cross-sectional study was
carried out among five rural communities in Malaysia to determine the prevalence of Giardia duodenalis in
humans, animals and river water. Fecal samples collected from humans and animals were examined by light
microscopy. Water was sampled from the rivers adjacent to the target communities and investigated for the
occurrence of Giardia cysts. The isolated cysts were further genotyped targeting the glutamate dehydrogenase
and triosephosphate isomerase genes. The overall prevalence of G. duodenalis was 6.7% (18/269) and 4.7% (8/
169) among humans and animals, respectively. Giardia cysts (mean concentration range: 0.10–5.97 cysts/L)
were also found in adjacent rivers at four out of the five villages examined. At Kemensah and Kuala Pangsun,
Giardia cysts were isolated from humans [rate: 3.7% each (of 54 each)], animals [rates: 6.3% (of 62) and 11.3%
(of 16), respectively] and river water [average concentration of 9 samples each: 0.83 ± 0.81 and 5.97 ± 7.00,
respectively]. For both villages at Pos Piah and Paya Lebar, 12.2% (of 98) and 6.1% (of 33) of collected human
samples were infected, respectively whilst none of the collected animals samples in these villages were found to
be positive. The river water samples of these two villages were also contaminated (average concentration:
0.20 ± 0.35 (of 9) and 0.10 ± 0.19 (of 3), respectively). In conclusion, Giardia cysts were simultaneously
observed in the human-animal-environment (i.e., river water) interfaces in at least two of five studied communities highlighting a vital need to improve understanding on the interplay of transmission dynamics, the role
of infected humans and animals in contaminating the water sources and the role of water as a vehicle of disease
transmission in these communities. Indeed, this study illustrates the One Health approach which is to recognize
that the optimal health of humans are interconnected with the well-being of animals and their environment
Detection of Schistosoma mansoni and Schistosoma haematobium by Real-Time PCR with High Resolution Melting Analysis
The present study describes a real-time PCR approach with high resolution melting-curve (HRM) assay developed for the detection and differentiation of Schistosoma mansoni and S. haematobium in fecal and urine samples collected from rural Yemen. The samples were screened by microscopy and PCR for the Schistosoma species infection. A pair of degenerate primers were designed targeting partial regions in the cytochrome oxidase subunit I (cox1) gene of S. mansoni and S. haematobium using real-time PCR-HRM assay. The overall prevalence of schistosomiasis was 31.8%; 23.8% of the participants were infected with S. haematobium and 9.3% were infected with S. mansoni. With regards to the intensity of infections, 22.1% and 77.9% of S. haematobium infections were of heavy and light intensities, respectively. Likewise, 8.1%, 40.5% and 51.4% of S. mansoni infections were of heavy, moderate and light intensities, respectively. The melting points were distinctive for S. mansoni and S. haematobium, categorized by peaks of 76.49 ± 0.25 °C and 75.43 ± 0.26 °C, respectively. HRM analysis showed high detection capability through the amplification of Schistosoma DNA with as low as 0.0001 ng/µL. Significant negative correlations were reported between the real-time PCR-HRM cycle threshold (Ct) values and microscopic egg counts for both S. mansoni in stool and S. haematobium in urine (p < 0.01). In conclusion, this closed-tube HRM protocol provides a potentially powerful screening molecular tool for the detection of S. mansoni and S. haematobium. It is a simple, rapid, accurate, and cost-effective method. Hence, this method is a good alternative approach to probe-based PCR assays
Detection of Naegleria Species in Environmental Samples from Peninsular Malaysia
In Malaysia, researchers and medical practitioners are unfamiliar with Naegleria infections. Thus little is known about the existence of pathogenic Naegleria fowleri, and the resultant primary amoebic meningoencephalitis (PAM) is seldom included in the differential diagnosis of central nervous system infections. This study was conducted to detect the presence of Naegleria species in various environmental samples.A total of 41 Naegleria-like isolates were isolated from water and dust samples. All these isolates were subjected to PCR using two primer sets designed from the ITS1-ITS2 regions. The N. fowleri species-specific primer set failed to produce the expected amplicon. The Naegleria genus-specific primers produced amplicons of 408 bp (35), 450 bp (2), 457 bp (2) or 381 bp (2) from all 41 isolates isolated from aquatic (33) and dust (8) samples. Analysis of the sequences from 10 representative isolates revealed that amplicons with fragments 408, 450 and 457 bp showed homology with non-pathogenic Naegleria species, and 381 bp showed homology with Vahlkampfia species. These results concurred with the morphological observation that all 39 isolates which exhibited flagella were Naegleria, while 2 isolates (AC7, JN034055 and AC8, JN034056) that did not exhibit flagella were Vahlkampfia species.To date, pathogenic species of N. fowleri have not been isolated from Malaysia. All 39 isolates that produced amplicons (408, 450 and 457 bp) from the genus-specific primers were identified as being similar to nonpathogenic Naegleria. Amplicon 408 bp from 5 representative isolates showed 100% and 99.7% identity to Naegleria philippinensis isolate RJTM (AM167890) and is thus believed to be the most common species in our environment. Amplicons 450 bp and 457 bp were respectively believed to be from 2 new species of Naegleria, since representative isolates showed lower homology and had a longer base pair length when compared to the reference species in the Genbank, Naegleria schusteri (AJ566626) and Naegleria laresi (AJ566630), respectively
PREVALENCE AND RISK FACTORS OF SCHISTOSOMIASIS AMONG HAUSA COMMUNITIES IN KANO STATE, NIGERIA
SUMMARY Schistosomiasis remains one of the most prevalent neglected tropical diseases especially in Nigeria which has the greatest number of infected people worldwide. A cross-sectional study was conducted among 551 participants from Kano State, North Central Nigeria. Fecal samples were examined for the presence of Schistosoma mansoni eggs using the formalin-ether sedimentation method while the urine samples were examined using the filtration technique for the presence of S. haematobium eggs. Demographic, socioeconomic and environmental information was collected using a pre-validated questionnaire. The overall prevalence of schistosomiasis was 17.8%, with 8.9% and 8.3% infected with S. mansoni and S. haematobium, respectively and 0.5% presenting co-infection with both species. The multiple logistic regression analysis revealed that age < 18 years (OR = 2.13; 95% CI; 1.34- 3.41), presence of infected family members (OR = 3.98; 95% CI; 2.13-7.46), and history of infection (OR = 2.87; 95% CI; 1.87- 4.56) were the significant risk factors associated with schistosomiasis in these communities. In conclusion, this study revealed that schistosomiasis is still prevalent among Hausa communities in Nigeria. Mass drug administration, health education and community mobilization are imperative strategies to significantly reduce the prevalence and morbidity of schistosomiasis in these communities
Strain differences in Blastocystis isolates as detected by a single set of polymerase chain reaction primers
A total of 20 isolates of Blastocystis were characterized using a single set of polymerase chain reaction (PCR) primers. The amplification product revealed five types of pattern. All four isolates from Singapore yielded PCR products quite different from those of the local isolates. However, most of the local isolates showed a major product at either 280 or 500 bp, or both. We also suspected that the amplification product detected at 280 bp might be an indicator of the pathogenicity of this parasite. One isolate (M12) obtained from a monkey showed patterns similar to those of human isolates (10203 and KP1) and probably belongs to the same strain. The results indicate that the intraspecific or interstrain variations in these 20 Blastocystis isolates belong to 5 different patterns. The differences among isolates of the same strain revealed by the presence or absence of certain amplification products showed further intrastrain variations in this parasite