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Fulltext The prevalence of simian malaria in wild long-tailed macaques throughout Peninsular Malaysia

Shahari S, Bin Abdullah ML, Binti Isman Rohimly AA, Binti Ashrat N, Amir A, Atroosh WMM, et al.

Sci Rep, 2024 Mar 12;14(1):6023.
PMID: 38472278 DOI: 10.1038/s41598-024-54981-2

The parasite Plasmodium knowlesi has been the sole cause of malaria in Malaysia from 2018 to 2022. The persistence of this zoonotic species has hampered Malaysia's progress towards achieving the malaria-free status awarded by the World Health Organisation (WHO). Due to the zoonotic nature of P. knowlesi infections, it is important to study the prevalence of the parasite in the macaque host, the long-tailed macaque (Macaca fascicularis). Apart from P. knowlesi, the long-tailed macaque is also able to harbour Plasmodium cynomolgi, Plasmodium inui, Plasmodium caotneyi and Plasmodium fieldi. Here we report the prevalence of the 5 simian malaria parasites in the wild long-tailed macaque population in 12 out of the 13 states in Peninsular Malaysia using a nested PCR approach targeting the 18s ribosomal RNA (18s rRNA) gene. It was found that all five Plasmodium species were widely distributed throughout Peninsular Malaysia except for states with major cities such as Kuala Lumpur and Putrajaya. Of note, Pahang reported a malaria prevalence of 100% in the long-tailed macaque population, identifying it as a potential hotspot for zoonotic transmission. Overall, this study shows the distribution of the 5 simian malaria parasite species throughout Peninsular Malaysia, the data of which could be used to guide future malaria control interventions to target zoonotic malaria.

Matched MeSH terms: Parasites*
Fulltext Antiparasitic potential of Nephrolepis biserrata methanol extract against the parasitic leech Zeylanicobdella arugamensis (Hirudinea) and LC-QTOF analysis

Shah MD, Venmathi Maran BA, Haron FK, Ransangan J, Ching FF, Shaleh SRM, et al.

Sci Rep, 2020 12 16;10(1):22091.
PMID: 33328532 DOI: 10.1038/s41598-020-79094-4

Marine leech Zeylanicobdella arugamensis (Piscicolidae), an economically important parasite is infesting predominantly cultured groupers, hybrid groupers and other fish in Southeast Asian countries. In this study, we tested the anti-parasitic potential of a medicinal plant Nephrolepis biserrata found in Sabah, East Malaysia against Z. arugamensis. Various concentrations of methanol extracts of the plant were tested experimentally against Z. arugamensis and disinfestation of the leech from its primary host hybrid groupers. The composition of methanol extract of N. biserrata was determined through LC-QTOF analysis. The significant anti-parasitic activity of 100% mortality of leeches was observed with the exposure of N. biserrata extracts. The average time to kill the leeches at concentrations of 25, 50 and 100 mg/ml was 25.11 ± 3.26, 11.91 ± 0.99, and 4.88 ± 0.50 min., respectively. Further, at various low concentrations of N. biserrata 2.5, 5 and 10 mg/ml, hybrid groupers were disinfested in an average time of 108.33 ± 12.65, 65.83 ± 9.70 and 29.16 ± 5.85 min., respectively. The tandem mass spectrometry data from LC-QTOF indicated some hits on useful bioactive compounds such as terpenoids (ivalin, isovelleral, brassinolide, and eschscholtzxanthin), flavonoids (alnustin, kaempferol 7,4'-dimethyl ether, and pachypodol), phenolics (piscidic acid, chlorogenic acid, and ankorine), and aromatic (3-hydroxycoumarin). Thus N. biserrata can act as a potential biocontrol agent.

Matched MeSH terms: Parasites/drug effects*; Parasites/pathogenicity
Fulltext Plasmodium-a brief introduction to the parasites causing human malaria and their basic biology

Sato S

J Physiol Anthropol, 2021 Jan 07;40(1):1.
PMID: 33413683 DOI: 10.1186/s40101-020-00251-9

Malaria is one of the most devastating infectious diseases of humans. It is problematic clinically and economically as it prevails in poorer countries and regions, strongly hindering socioeconomic development. The causative agents of malaria are unicellular protozoan parasites belonging to the genus Plasmodium. These parasites infect not only humans but also other vertebrates, from reptiles and birds to mammals. To date, over 200 species of Plasmodium have been formally described, and each species infects a certain range of hosts. Plasmodium species that naturally infect humans and cause malaria in large areas of the world are limited to five-P. falciparum, P. vivax, P. malariae, P. ovale and P. knowlesi. The first four are specific for humans, while P. knowlesi is naturally maintained in macaque monkeys and causes zoonotic malaria widely in South East Asia. Transmission of Plasmodium species between vertebrate hosts depends on an insect vector, which is usually the mosquito. The vector is not just a carrier but the definitive host, where sexual reproduction of Plasmodium species occurs, and the parasite's development in the insect is essential for transmission to the next vertebrate host. The range of insect species that can support the critical development of Plasmodium depends on the individual parasite species, but all five Plasmodium species causing malaria in humans are transmitted exclusively by anopheline mosquitoes. Plasmodium species have remarkable genetic flexibility which lets them adapt to alterations in the environment, giving them the potential to quickly develop resistance to therapeutics such as antimalarials and to change host specificity. In this article, selected topics involving the Plasmodium species that cause malaria in humans are reviewed.

Matched MeSH terms: Parasites
Fulltext Migrant Workers in Malaysia: Current Implications of Sociodemographic and Environmental Characteristics in the Transmission of Intestinal Parasitic Infections

Sahimin N, Lim YA, Ariffin F, Behnke JM, Lewis JW, Mohd Zain SN

PLoS Negl Trop Dis, 2016 Nov;10(11):e0005110.
PMID: 27806046 DOI: 10.1371/journal.pntd.0005110

A cross-sectional study of intestinal parasitic infections amongst migrant workers in Malaysia was conducted. A total of 388 workers were recruited from five sectors including manufacturing, construction, plantation, domestic and food services. The majority were recruited from Indonesia (n = 167, 43.3%), followed by Nepal (n = 81, 20.9%), Bangladesh (n = 70, 18%), India (n = 47, 12.1%) and Myanmar (n = 23, 5.9.2%). A total of four nematode species (Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis and hookworms), one cestode (Hymenolepis nana) and three protozoan species (Entamoeba histolytica/dispar, Giardia sp. and Cryptosporidium spp.) were identified. High prevalence of infections with A. lumbricoides (43.3%) was recorded followed by hookworms (13.1%), E. histolytica/dispar (11.6%), Giardia sp. (10.8%), T. trichura (9.5%), Cryptosporodium spp. (3.1%), H. nana (1.8%) and E. vermicularis (0.5%). Infections were significantly influenced by socio-demographic (nationality), and environmental characteristics (length of working years in the country, employment sector and educational level). Up to 84.0% of migrant workers from Nepal and 83.0% from India were infected with intestinal parasites, with the ascarid nematode A. lumbricoides occurring in 72.8% of the Nepalese and 68.1% of the Indian population. In addition, workers with an employment history of less than a year or newly arrived in Malaysia were most likely to show high levels of infection as prevalence of workers infected with A. lumbricoides was reduced from 58.2% to 35.4% following a year's residence. These findings suggest that improvement is warranted in public health and should include mandatory medical screening upon entry into the country.

Matched MeSH terms: Parasites/classification; Parasites/genetics; Parasites/isolation & purification*
Fulltext STUDY OF MORPHOLOGY, PREVALENCE AND MEAN INTENSITY OF MONOGENEANS INFECTING POND REARED Pangasianodon hypophthalmus(STRIPED CATFISH) IN BESUT, TERENGGANU

SARAH SALEHAH

UMT Journal of Undergraduate Research, 2019;1(1):33-40.
MyJurnal

This study was conducted to determine the morphology, prevalence and mean intensity of monogeneans on gill filaments of striped catfish Pangasianodon hypophthalmus (Pangasiidae).P. hypophthalmus are important economic fish in Southeast Asia region and predominantly produced in Asian countries such as Malaysia, Bangladesh, Indonesia, Vietnam, Laos, China and Cambodia through aquaculture. Thirty fish were sampled from an earthen pond located in Kuala Besut, Terengganu, in the period from January to February, 2018. The monogenean parasites were removed from the gill filaments and counted. For the morphological study, the extracted monogeneanswere mounted on a slide by using drop of ammonium picrate-glycerin (APG) and then were observed under the Compound Advanced Research Microscope. The drawing was done with the aid of lucida camera attached to compound microscope. The monogenean parasite was identified as Thaparocleidussp based on the characteristics of the morphology and morphometrics of the parasite, which did not differ significantly from the previous descriptions of the same species discovered in other geographic locations. The prevalence and mean intensity levels were 100% and 106.07 parasites per fish, respectively. The monogenean parasites discovered throughout this examination were recorded and the data obtained was summarized.

Matched MeSH terms: Parasites
Fulltext Is it safe to prescribe triple drugs therapy for lymphatic filariasis infection in Epidermolysis Bullosa patient? a case report

S. Izuddin, Nur Dalila Zakaria, Nur L. A., Omar K. K.

Malaysian Journal of Medicine and Health Sciences, 2019;15(106):85-85.
MyJurnal

Introduction:Filariasis is an endemic infection in tropical and subtropical countries. The disease is caused by para-sites from the group filarodidae. Epidermolysis Bullosa, on the other hand is a group of rare genetic skin diseases that characterize by skin blister and erode facilely. Due to rarity of Epidermolysis Bullosa and uncommon occurrence of Filariasis, there is extremely limited case or paper reporting on safety profile of medication that are used to treat Filariasis patient with underlying Epidermolysis Bullosa.Serious adverse event that is anticipated in this cohort of patient are Stevens-Johnson syndrome and Mazotti reaction. Case description: Surveillance activity is necessary in high endemic localities in Sabah in order to control the spread of this mosquitoes-borne disease. The available tool is Brugia RapidTM kit, a test kit that detects filarial antibodies.A 13 year-old boy with underlying Epidemolysis Bullosa Simplex was detected during surveillance activities. It was further confirmed with night blood on microscopic slide that depicted high density of parasite (microfilaria count: 31). The WHO specifically exempted the following groups from the treatment - children under 5 years of age; pregnant women; and seriously ill individuals i.e. those who are having acute or chronic illness that makes them too sick or weak to get out of bed; and those with an illness who are life-dependent on medical intervention. This is because ingestion of the medications can result in adverse events due to the destruction of killed parasites. No guideline is available for treatment of lymphatic filariasis in rare genetic disorders. Conclusion: The recommended dosage for IDA is Ivermectin 3mcg/kg, Diethylcarbamazine 6mg/kg and Albendazole 400mg for positive patient yearly. Patient was admitted in hospital for observation treatment with the suggested dose. From the case study it shows it is safe to treat this cohort patient. However, it is advisable to treat such rare cases by case basis and in comparison to others where treatment is given in the community this patients should be treat in more control environment such in the hospital.

Matched MeSH terms: Parasites
Fulltext Filariasis of the axilla in a patient returning from travel abroad: a case report

Roethlisberger M, Wuerstlein R, Majores M, Müller-Stöver I, Seitz HM, Rhiem K, et al.

Breast care (Basel, Switzerland), 2012 Dec;7(6):487-9.
PMID: 24715832 DOI: 10.1159/000345471

BACKGROUND: The term filariasis comprises a group of parasitic infections caused by helminths belonging to different genera in the superfamily Filaroidea. The human parasites occur mainly in tropical and subtropical regions, but filariae are also found in temperate climates, where they can infect wild and domestic animals. Humans are rarely infected by these zoonotic parasites.
PATIENTS AND METHODS: A 55-year-old patient presented with a new-onset, subcutaneous, non-tender palpable mass in the right axilla. Ultrasonography showed a 1.3-cm, solid, singular encapsulated node. Sonography of the breast on both sides, axilla and lymphatic drainage on the left side, lymphatic drainage on the right side, and mammography on both sides were without pathological findings. The node was excised under local anesthesia as the patient refused minimal invasive biopsy.
RESULTS: On histopathological examination, the tail of a parasite of the group of filariae was found. The patient revealed that she had stayed in Africa and Malaysia for professional reasons. 6 months before the time of diagnosis, she had also suffered from a fever and poor general condition after a trip abroad. The patient was referred for further treatment to the Institute for Tropical Medicine at the University of Dusseldorf, where a treatment with ivermectin was conducted on the basis of positive staining with antibodies against filariae.
CONCLUSION: Our case demonstrates the importance of interdisciplinary collaboration between breast center, pathology, and other specialties such as microbiology and tropical medicine.

Matched MeSH terms: Parasites
Fulltext Molecular Identification of Giardia duodenalis Isolates from Fars Province, Iran

Rayani M, Zasmy Unyah N, Hatam G

Iran J Parasitol, 2014 Mar;9(1):70-8.
PMID: 25642262

Giardia duodenalis is one of the most common human intestinal protozoan parasites worldwide and is endemic throughout the world with a vast range of mammalian hosts. The present study aimed to identify the prevalence of G. duodenalis isolates and determine the most common of its assemblages in the patients referring to health centers and hospitals in Fars province, Iran that will be subjected to further molecular investigation.

Matched MeSH terms: Parasites
Fulltext Genetic diversity and natural selection in the rhoptry-associated protein 1 (RAP-1) of recent Plasmodium knowlesi clinical isolates from Malaysia

Rawa MS, Fong MY, Lau YL

Malar J, 2016;15:62.
PMID: 26847346 DOI: 10.1186/s12936-016-1127-7

The Plasmodium rhoptry-associated protein 1 (RAP-1) plays a role in the formation of the parasitophorous vacuole following the parasite's invasion of red blood cells. Although there is some evidence that the protein is recognized by the host's immune system, study of Plasmodium falciparum RAP-1 (PfRAP-1) suggests that it is not under immune pressure. A previous study on five old (1953-1962) P. knowlesi strains suggested that RAP-1 has limited genetic polymorphism and might be under negative selection. In the present study, 30 recent P. knowlesi isolates were studied to obtain a better insight into the polymorphism and natural selection of PkRAP-1.

Matched MeSH terms: Parasites
Prevalence and intensity of helminths among inhabitants of the Chi River and Lahanna water reservoir areas of Northeastern Thailand

Rattanapitoon SK, Pechdee P, Boonsuya A, Meererksom T, Wakkhuwatapong P, Leng M, et al.

Trop Biomed, 2020 Sep 01;37(3):730-743.
PMID: 33612786 DOI: 10.47665/tb.37.3.730

Helminth infections (HIs) are an important public health problem in tropical countries, and the associated problems have been neglected in rural areas of Thailand. Therefore, this study reports the prevalence and intensity of HIs among inhabitants of the Khon Sawan district, Chaiyaphum province, and Kaeng Samnam Nang district, Nakhon Ratchasima province, which are located near the Chi River and Lahanna water reservoir, northeastern Thailand. A cross-sectional descriptive study was conducted between July 31, 2018, and June 30, 2019, among rural villagers from 40 rural villages in 4 subdistricts. The participants were selected from the village enrolment list after proportional allocation of the total sample size. Faecal samples from 691 inhabitants were prepared using solvent-free faecal parasite concentrator, and helminths were then detected using a light microscope. Statistical analysis included the Chi-square test with Yates correction, and multivariable logistic regression was performed. A P-value of <0.05 was considered statistically significant. The prevalence of HIs was 2.03%. The most prevalent helminths were Opisthorchis viverrini (1.31%), followed by Strongyloides stercoralis (0.44%), Ascaris lumbricoides (0.29%), hookworm (0.15%), Teania spp. (0.15%) and one minute intestinal fluke (0.15%). Coinfections were identified in 2 cases for S. stercoralis and hookworm and 1 case for O. viverrini and S. stercoralis infection. All infected participants had a light intensity of HI. There was no significant difference between general characteristics for all HIs. The prevalence of HIs was not significantly associated with general characteristics. This study indicates that the infections result mainly from foodborne helminths and skin-penetrating nematodes. Therefore, interventions should concentrate on the personal hygiene of the population and improving sanitation to reduce HIs in this area.

Matched MeSH terms: Parasites
Fulltext Prevalence of malaria and its risk factors in Sabah, Malaysia

Ramdzan AR, Ismail A, Mohd Zanib ZS

Int J Infect Dis, 2019 Nov 27;91:68-72.
PMID: 31785400 DOI: 10.1016/j.ijid.2019.11.026

OBJECTIVES: The aim of this study was to determine the prevalence of malaria in Sabah and its potential risk factors.
METHODS: This cross-sectional study analysed secondary data obtained from the health clinics in Sabah, Malaysia from January to August 2016. The Pearson Chi-square test was used to analyse the relationships between malaria infection and socio-demographic characteristics. Multivariable logistic regression was performed in order to determine the risk factors for malaria in Sabah.
RESULTS: Out of 1222 patients, 410 (33.6%) had a laboratory-confirmed malaria infection. Infection by Plasmodium knowlesi accounted for the majority of malaria reports in Sabah (n=340, 82.9%). Multivariable analysis indicated that males (prevalence odds ratio 0.023, 95% confidence interval 0.012-0.047) and those living in a rural area (prevalence odds ratio 0.004, 95% confidence interval 0.002-0.009) were at higher risk 24.0-95.9) and those living in a rural area (adjusted odds ratio 212.6, 95% confidence interval 105.8-427.2) were at higher risk of acquiring a malaria infection.
CONCLUSIONS: Malaria infections in Sabah, Malaysia are common, with P. knowlesi being the most common malaria parasite. The infection was associated with several socio-demographic and geographical factors. Thus, mitigation measures should be considered to address modifiable risk factors for malaria infection.

Matched MeSH terms: Parasites
Fulltext Neglected Intestinal Parasites, Malnutrition and Associated Key Factors: A Population Based Cross-Sectional Study among Indigenous Communities in Sarawak, Malaysia

Rajoo Y, Ambu S, Lim YA, Rajoo K, Tey SC, Lu CW, et al.

PLoS One, 2017;12(1):e0170174.
PMID: 28095446 DOI: 10.1371/journal.pone.0170174

Intestinal parasitic infections (IPIs) have been recognized as one of the most significant causes of illness among disadvantaged communities. Many studies have been conducted on the prevalence of IPIs in Malaysia. However, these studies mostly focused on the indigenous groups in Peninsular Malaysia. The present study was conducted to provide the current baseline data on prevalence of IPIs, anaemia, malnutrition and associated risk factors among the indigenous communities in Sarawak, situation at northwest Borneo island of Malaysia. A cross sectional study was conducted among the longhouses communities. Stool samples were obtained and examined for the presence of IPIs using microscopy technique. Haemoglobin measurement was done using a portable haemoglobin analyzer. Malnutrition (i.e., stunting, underweight and wasting) was assessed using the WHO Anthro software. Statistical analysis was carried out using SPSS software. A total of 341participants took part in this study. The overall prevalence of IPIs was 57.5%. Multivariate analysis indicated that the absence of toilets (OR = 1.6; 95% CI = 1.1-2.7; p = 0.002) and close contact with animals (OR = 1.8; 95% CI = 1.3-2.9; p = 0.027) as significant predictors for IPIs. The incidence of anaemia was 36.4%. The incidence of underweight, wasting and stunting were 22.2%, 5.6% and 35.4%, respectively. Multivariate analysis demonstrated that low level of parental education attainment (OR = 1.9; 95% CI = 1.2-3.0; p = 0.006) was identified as significant predictor for anaemia. The incidence of wasting was significantly associated with mild anaemia (OR = 1.2; 95% CI = 0.9-1.7; p = 0.024). Low household income was identified as significant predictor for stunting (OR = 2.1; 95% CI = 9.8-22.2; p = 0.001) and underweight (OR = 1.9; 95% CI = 5.6-18.7; p = 0.037), respectively. Essentially, the present study highlighted that intestinal parasitic infections, anaemia and malnutrition are still prevalent among rural indigenous community in Sarawak. Improvement of socioeconomic status, periodic mass deworming, iron supplementation and health education program should be included in the control and prevention of public health strategies.

Matched MeSH terms: Parasites/pathogenicity*
Fulltext Naturally Acquired Human Plasmodium cynomolgi and P. knowlesi Infections, Malaysian Borneo

Raja TN, Hu TH, Kadir KA, Mohamad DSA, Rosli N, Wong LL, et al.

Emerg Infect Dis, 2020 08;26(8):1801-1809.
PMID: 32687020 DOI: 10.3201/eid2608.200343

To monitor the incidence of Plasmodium knowlesi infections and determine whether other simian malaria parasites are being transmitted to humans, we examined 1,047 blood samples from patients with malaria at Kapit Hospital in Kapit, Malaysia, during June 24, 2013-December 31, 2017. Using nested PCR assays, we found 845 (80.6%) patients had either P. knowlesi monoinfection (n = 815) or co-infection with other Plasmodium species (n = 30). We noted the annual number of these zoonotic infections increased greatly in 2017 (n = 284). We identified 6 patients, 17-65 years of age, with P. cynomolgi and P. knowlesi co-infections, confirmed by phylogenetic analyses of the Plasmodium cytochrome c oxidase subunit 1 gene sequences. P. knowlesi continues to be a public health concern in the Kapit Division of Sarawak, Malaysian Borneo. In addition, another simian malaria parasite, P. cynomolgi, also is an emerging cause of malaria in humans.

Matched MeSH terms: Parasites
Gastrointestinal Parasites in Asian and African Elephants: A Systematic Review

Qurratul-Saadah Z, Che-Amat A, Syed-Hussain SS, Kamaludden J, Ariffin SMZ, Basripuzi NH, et al.

Trop Biomed, 2023 Mar 01;40(1):55-64.
PMID: 37356004 DOI: 10.47665/tb.40.1.012

Gastrointestinal parasites (GIPs) in elephants have been reported in several studies over the last decades. Nonetheless, comprehensive data on clinicopathology of elephant GIPs, parasite burden threshold value, and the effectiveness of conventional anthelmintic drugs are still lacking. Herein, we have systematically reviewed the available knowledge on elephant GIPs identified among different parts of the world based on their prevalence, epidemiology, pathology, diagnosis, treatment, and control. Two electronic databases were searched for publications that met the inclusion criteria. About19 English journal articles published between year of 2011- 2021 were included. The main GIPs reported in elephants were Cyathostomidae (at least 14 species), Ancylostomidae, Haemonchus contortus, Trichostrongylus colubriformis, Oesophagostomum columbianum, Oesophagostomum aceleatum, Ascarids, Trichurids, Strongyloides, Anophlocephalidae, flukes, and Coccidia across different parts of the world, including Malaysia, Indonesia, Thailand, Myanmar, Sri Lanka, India, Kenya, Nigeria, and South Africa. Most elephants show no clinical signs until the equilibrium between parasite and host is disturbed. The common diagnostic methods for GIPs are traditional direct smear, faecal floatation, sedimentation, and McMaster egg counting technique, all involving morphological identification. However, some articles described the use of molecular detection to characterise common GIPs of elephants. Although benzimidazoles and macrocyclic lactones group of anthelmintic are the most conventional GIPs treatment and control for captive and semi-captive elephants, there is limited data on the threshold value of faecal egg count as the baseline for treatment decision. Over the last decades, various studies regarding elephant GIPs have been conducted. However, more focused and systematic studies are required to enhance our knowledge in multiple aspects of elephant parasitology to find effective solutions and improve elephant health.

Matched MeSH terms: Parasites*
Fulltext Antibodies in children with malaria to PfEMP1, RIFIN and SURFIN expressed at the Plasmodium falciparum parasitized red blood cell surface

Quintana MDP, Ch'ng JH, Moll K, Zandian A, Nilsson P, Idris ZM, et al.

Sci Rep, 2018 02 19;8(1):3262.
PMID: 29459776 DOI: 10.1038/s41598-018-21026-4

Naturally acquired antibodies to proteins expressed on the Plasmodium falciparum parasitized red blood cell (pRBC) surface steer the course of a malaria infection by reducing sequestration and stimulating phagocytosis of pRBC. Here we have studied a selection of proteins representing three different parasite gene families employing a well-characterized parasite with a severe malaria phenotype (FCR3S1.2). The presence of naturally acquired antibodies, impact on rosetting rate, surface reactivity and opsonization for phagocytosis in relation to different blood groups of the ABO system were assessed in a set of sera from children with mild or complicated malaria from an endemic area. We show that the naturally acquired immune responses, developed during malaria natural infection, have limited access to the pRBCs inside a blood group A rosette. The data also indicate that SURFIN4.2 may have a function at the pRBC surface, particularly during rosette formation, this role however needs to be further validated. Our results also indicate epitopes differentially recognized by rosette-disrupting antibodies on a peptide array. Antibodies towards parasite-derived proteins such as PfEMP1, RIFIN and SURFIN in combination with host factors, essentially the ABO blood group of a malaria patient, are suggested to determine the outcome of a malaria infection.

Matched MeSH terms: Parasites
Sequence diversity and positive selection at the Duffy-binding protein genes of Plasmodium knowlesi and P. cynomolgi: Analysis of the complete coding sequences of Thai isolates

Putaporntip C, Kuamsab N, Jongwutiwes S

Infect Genet Evol, 2016 Oct;44:367-375.
PMID: 27480919 DOI: 10.1016/j.meegid.2016.07.040

Plasmodium knowlesi and P. cynomolgi are simian malaria parasites capable of causing symptomatic human infections. The interaction between the Duffy binding protein alpha on P. knowlesi merozoite and the Duffy-antigen receptor for chemokine (DARC) on human and macaque erythrocyte membrane is prerequisite for establishment of blood stage infection whereas DARC is not required for erythrocyte invasion by P. cynomolgi. To gain insights into the evolution of the PkDBP gene family comprising PkDBPα, PkDBPβ and PkDBPγ, and a member of the DBP gene family of P. cynomolgi (PcyDBP1), the complete coding sequences of these genes were analyzed from Thai field isolates and compared with the publicly available DBP sequences of P. vivax (PvDBP). The complete coding sequences of PkDBPα (n=11), PkDBPβ (n=11), PkDBPγ (n=10) and PcyDBP1 (n=11) were obtained from direct sequencing of the PCR products. Nucleotide diversity of DBP is highly variable across malaria species. PcyDBP1 displayed the greatest level of nucleotide diversity while all PkDBP gene members exhibited comparable levels of diversity. Positive selection occurred in domains I, II and IV of PvDBP and in domain V of PcyDBP1. Although deviation from neutrality was not detected in domain II of PkDBPα, a signature of positive selection was identified in the putative DARC binding site in this domain. The DBP gene families seem to have arisen following the model of concerted evolution because paralogs rather than orthologs are clustered in the phylogenetic tree. The presence of identical or closely related repeats exclusive for the PkDBP gene family suggests that duplication of gene members postdated their divergence from the ancestral PcyDBP and PvDBP lineages. Intragenic recombination was detected in all DBP genes of these malaria species. Despite the limited number of isolates, P. knowlesi from Thailand shared phylogenetically related domain II sequences of both PkDBPα and PkDBPγ with those from Peninsular Malaysia, consistent with their geographic proximity.

Matched MeSH terms: Parasites
Fulltext Capsid structure of Leishmania RNA virus 1

Procházková M, Füzik T, Grybchuk D, Falginella F, Podešvová L, Yurchenko V, et al.

J Virol, 2020 Nov 18.
PMID: 33208443 DOI: 10.1128/JVI.01957-20

Leishmania parasites cause a variety of symptoms, including mucocutaneous leishmaniasis, which results in the destruction of the mucous membranes of the nose, mouth, and throat. The species of Leishmania carrying Leishmania RNA virus 1 (LRV1), from the family Totiviridae, are more likely to cause severe disease and are less sensitive to treatment than those that do not contain the virus. Although the importance of LRV1 for the severity of leishmaniasis was discovered a long time ago, the structure of the virus remained unknown. Here, we present a cryo-electron microscopy reconstruction of the virus-like particle of LRV1 determined to a resolution of 3.65 Å. The capsid has icosahedral symmetry and is formed by 120 copies of a capsid protein assembled in asymmetric dimers. RNA genomes of viruses from the family Totiviridae are synthetized, but not capped at the 5' end, by virus RNA-polymerases. To protect viral RNAs from degradation, capsid proteins of totivirus L-A cleave the 5' caps of host mRNAs, creating decoys to overload the cellular RNA quality control system. Capsid proteins of LRV1 form positively charged clefts, which may be the cleavage sites for the 5' cap of Leishmania mRNAs. Capsid proteins of LRV1 contain a putative RNA binding site distinct from that of the related L-A virus. The structure of the LRV1 capsid enables the rational design of compounds targeting the putative de-capping site. Such inhibitors may be developed into a treatment for mucocutaneous leishmaniasis caused by LRV1-positive species of LeishmaniaIMPORTANCE Twelve million people worldwide suffer from leishmaniasis, resulting in more than thirty thousand deaths annually. The disease has several variants that differ in their symptoms. The mucocutaneous form, which leads to disintegration of the nasal septum, lips, and palate, is predominantly caused by Leishmania parasites carrying Leishmania RNA virus 1 (LRV1). Here, we present the structure of the LRV1 capsid determined using cryo-electron microscopy. Capsid proteins of a related totivirus L-A protect viral RNAs from degradation by cleaving the 5' caps of host mRNAs. Capsid proteins of LRV1 may have the same function. We show that the LRV1 capsid contains positively charged clefts that may be sites for the cleavage of mRNAs of Leishmania cells. The structure of the LRV1 capsid enables the rational design of compounds targeting the putative mRNA cleavage site. Such inhibitors may be used as treatments for muco-cutaneous leishmaniasis.

Matched MeSH terms: Parasites
Pentastomiasis: a common finding at autopsy among Malaysian aborigines

Prathap K, Lau KS, Bolton JM

Am J Trop Med Hyg, 1969 Jan;18(1):20-7.
PMID: 5812657
Matched MeSH terms: Parasites*
Fulltext The health of Malaysia’s “Orang Asli” peoples: a review of the scientific evidence on nutritional outcome, parasite infestations, and discussion on implications for clinical practice

Phua, K.L.

Malaysian Journal of Public Health Medicine, 2015;15(1):0-0.
MyJurnal

The Orang Asli of Malaysia continue to experience poor health. There appears to be stagnation of certain aspect of their health status. Underweight (low weight-for-age) and stunting (low height-for-age) are significant amongst Orang Asli children. Worm infestation such as Ascaris, Trichuris and hookworm continue to afflict Orang Asli communities in Malaysia. Orang Asli communities can also be afflicted by other kinds of parasites, e.g. malaria parasites, microsporida parasites and Cryptosporidium parasites. Thus, primary care doctors who treat Orang Asli patients should be on the lookout for malnutrition and its effects (including anaemia, iodine deficiency, Vitamin A deficiency) as well as worm and parasite infestations. Such patients may need to undergo de-worming at regular intervals because of the tendency to get re-infected. Primary care doctors also need to be aware of possible interactions between infestations and nutritional deficiencies.

Matched MeSH terms: Parasites
Fulltext Maggots from tracheostoma

Periasamy, Chentilnathan, Irfan Mohamad, Khairul Bariah Johan, Nik Fariza Husna Nik Hassan

Archives of Orofacial Sciences, 2013;8(1):41-43.
MyJurnal

Tracheostomy is a life saving surgical procedure performed to maintain upper airway ventilation. The
indications include providing relief of upper airway obstruction, to replace endotracheal intubation in patients needing prolonged assisted ventilation, protection of tracheobronchial tree and facilitates tracheobronchial toilet.More importantly, post operative tracheostomy care is very crucial for the success of the treatment and avoiding complications. We report a rare case of an obligate parasite which had infested the tracheal stoma due to poorhygiene.

Matched MeSH terms: Parasites

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