Malaria is still a very real threat to health in S.E. Asia including Malaysia. While there has been a dramatic fall in the number of cases and also the number of deaths from the disease in Malaysia cases are still occurring and there has actually been a rise in the number of deaths in the past year. Parts of Perak and the East Coast states are still high risk areas in Peninsular Malaysia. While 95 percent of the population of Peninsular Malaysia is now malaria-free there has also been a concomitant loss of herd immunity which means that if a non-immune person contracts falciparum malaria he stands a greater chance of a fatal outcome. Doctors and other health personnel should be more malaria conscious and make a practice of making blood films of all cases of fever. This is especially important in the rural areas and Estate Hospital Assistants must be encouraged to look for malaria parasites in their fever patients. The younger generation of EHAs have little experience of malaria and a definite policy of education to bring them up to date in antimalarial work and microscopic detection of the parasite should be under taken by the industry. Some problems of chemotherapy and drug resistance are discussed.
Simian malaria is a zoonotic disease caused by Plasmodium knowlesi infection. The common natural reservoir of the parasite is the macaque monkey and the vector is the Anopheles mosquito. Human cases of P. knowlesi infection has been reported in all South East Asian countries in the last decade, and it is currently the most common type of malaria seen in Malaysia and Brunei. Between 2007-2017, 73 cases of P. knowlesi infection were notified and confirmed to the Ministry of Health in Brunei. Of these, 15 cases (21%) were documented as work-related, and 28 other cases (38%) were classified as probably related to work (due to incomplete history). The occupations of those with probable and confirmed work related infections were border patrol officers, Armed Forces and security personnel, Department of Forestry officers, boatmen and researchers. The remaining cases classified as most likely not related to work were possibly acquired via peri-domestic transmission. The risk of this zoonotic infection extends to tourists and overseas visitors who have to travel to the jungle in the course of their work. It can be minimised with the recommended use of prophylaxis for those going on duty into the jungles, application of mosquito/insect repellants, and use of repellant impregnated uniforms and bed nets in jungle camp sites.
Due to their unusual life cycle that includes parasitic larval and free living adult stages, gnathiid isopods are typically overlooked in biodiversity surveys, even those that focus on parasites. While the Philippines sits within the region of highest marine biodiversity in the world, the coral triangle, no gnathiid species have been identified or described from that region. Here we present the first records of two gnathiid species collected from the Visayas, central Philippines: Gnathia malaysiensis Müller, 1993, previously described from Malaysia, and G. camuripenis Tanaka, 2004, previously described from southern Japan. This paper provides detailed morphological redescriptions, drawings and scanning electron microscope images as well as the first molecular characterisation of both species, Furthermore, a summary of the Central-Indo Pacific Gnathia species is provided.
Food safety issues associated with aquatic food products become more important with the increasing consumption and followed by its ongoing challenges. The objective of this paper is to review the food safety hazards and health risks related to aquatic food products for the Southeast Asian region. These hazards can be categorized as microplastics (MPs) hazard, biological hazards (pathogenic bacteria, biogenic amines, viruses, parasites), and chemical hazards (antimicrobial, formaldehyde, heavy metal). In different Southeast Asian countries, the potential health risks of aquatic food products brought by food hazards to consumers were at different intensity and classes. Among all these hazards, pathogenic bacteria, antimicrobials, and heavy metal were a particular concern in the Southeast Asian region. With environmental changes, evolving consumption patterns, and the globalization of trade, new food safety challenges are created, which put forward higher requirements on food technologies, food safety regulations, and international cooperation.
Protein kinases (PKs) are regulators of protein phosphorylation in many infectious diseases, including malaria. How- ever, the cellular functions of majority of PKs in Plasmodium falciparum remain unknown. The mechanisms involved in P. falciparum cell cycle progress are not fully understood. The activation of cyclin-dependent kinases (CDKs), which constitute a PK family that includes crucial regulators of cell cycle progression in eukaryotes, is strictly being coordinated by the interaction with specific cyclins at well-defined points within the cell cycle. These cyclin/CDK complexes are very well characterised in humans, but little is known in P. falciparum. This review expand our un- derstanding of the characteristic of CDKs and cyclins in P. falciparum, and paves the way for further investigations on the precise molecular role of these crucial regulatory proteins in mosquito and human. This represents a valuable step towards the elucidation of cell cycle control mechanisms in malaria parasites.
Haemosporidians infect a wide diversity of bat genera and species, yet little is known about their transmission cycles or epidemiology. Though several recent studies have focused on the genus Hepatocystis, an Old World parasite primarily infecting bats, monkeys, and squirrels, this group is still understudied with little known about its transmission and molecular ecology. These parasites lack an asexual erythrocytic stage, making them unique from the Plasmodium vertebrate life cycle. In this study, we detected a prevalence of 31% of Hepatocystis in short-nosed fruit bats (Cynopterus brachyotis) in Singapore. Phylogenetic reconstruction with a partial cytochrome b sequence revealed a monophyletic group of Hepatocystis from C. brachyotis in Malaysia, Singapore, and Thailand. There was no relationship with infection and bat age, sex, location, body condition or monsoon season. The absence of this parasite in the five other bat species sampled in Singapore indicates this Hepatocystis species may be host restricted.
Malaria, a mosquito-transmitted parasitic disease, has been targeted for elimination in many parts of the world. For many years, Plasmodium vivax, Plasmodium falciparum, Plasmodium ovale and Plasmodium malariae have been known to cause malaria in humans. Now, Plasmodium knowlesi is considered to be an important cause of malaria, especially in Southeast Asia. The emergence of P. knowlesi with zoonotic implication is a challenge in the elimination efforts of malaria in Southeast Asia. P. knowlesi is known to cause severe complicated malaria in humans. P. knowlesi parasite is transmitted between humans and wild macaque through mosquito vectors. It appears that the malaria disease severity and host immune evasion depend on antigenic variation exhibited at the surface of the infected erythrocyte. P. knowlesi is sensitive to antimalarial drug artemisinin. Identification of vector species, their biting behavior, timely correct diagnosis, and treatment are important steps in disease management and control. There is a need to identify and implement effective intervention measures to cut the chain of transmissions from animals to humans. The zoonotic malaria definitely poses a significant challenge in elimination and subsequent eradication of all types of malaria from this globe.
The Labroides dimidiatus is known as the "doctor fish" because of its role in removing parasites and infectious pathogens from the body of other fishes. This important role played both in wild and captive conditions could represent a novel form of parasitic transmission process mediated by the cleaning activity of the fish. Yet, there is a paucity of data on the microflora associated with this fish which is important for tracking disease infection and generally monitoring the health status of the fish. This article, therefore, represents the first dataset for the microbiota composition of wild and captive L. dimidiatus. Wild fish samples and carriage water were gotten in Terengganu Malaysia around the corals of the Karah Island. The captive sample, however, was obtained from well-known ornamental fish suppliers in Terengganu Malaysia. Thereafter, bacteria present on the skin, in the stomach and the aquarium water were enumerated using culture-independent approaches and Next Generation Sequencing (NGS) technology. Data obtained from the three metagenomic libraries using NGS analysis gave 1,426,740 amplicon sequence reads which are composed of 508 operational taxonomic units (OTUs) for wild samples and 3,238,564 valid reads and 828 OTUs for captive samples. All sequence reads were deposited in the GeneBank (Accession numbers SAMN14260247, SAMN14260248, SAMN14260249, SAMN14260250, SAMN14260251, and SAMN14260252). The dataset presented is associated with the research article "16S rDNA-Based Metagenomic Analysis of Microbial Communities Associated with Wild Labroides dimidiatus From Karah Island, Terengganu, Malaysia" [1]. The microbiota data presented in this article can be used to monitor the health and wellbeing of the ornamental fish, especially under captivity, hence preventing possible cross-infection.
The transmission of zoonotic filarial parasites by black flies has so far been reported in the Chiang Mai and Tak provinces, Thailand, and the bites of these infected black flies can cause a rare disease-human zoonotic onchocerciasis. However, species identification of the filarial parasites and their black fly vectors in the Chiang Mai province were previously only based on a morphotaxonomic analysis. In this study, a combined approach of morphotaxonomic and molecular analyses (mitochondrial cox1, 12S rRNA, and nuclear 18S rRNA (SSU HVR-I) genes) was used to clarify the natural filarial infections in female black flies collected by using human and swine baits from two study areas (Ban Lek and Ban Pang Dang) in the Chiang Mai province from March 2018 to January 2019. A total of 805 and 4597 adult females, belonging to seven and nine black fly taxa, were collected from Ban Lek and Ban Pang Dang, respectively. At Ban Lek, four of the 309 adult females of Simulium nigrogilvum were positive for Onchocerca species type I in the hot and rainy seasons. At Ban Pang Dang, five unknown filarial larvae (belonging to the same new species) were detected in Simulium sp. in the S. varicorne species-group and in three species in the S. asakoae species-group in all seasons, and three non-filarial larvae of three different taxa were also found in three females of the S. asakoae species-group. This study is the first to molecularly identify new filarial species and their vector black fly species in Thailand.
Gastrointestinal myxosporean parasites from the genus Enteromyxum are known to cause severe disease, resulting in high mortalities in numerous species of cultured marine fishes globally. Originally described as Myxidium spp., they were transferred to a new genus, Enteromyxum, to emphasize their novel characteristics. Their retention in the family Myxidiidae at the time was warranted, but more comprehensive phylogenetic analyses have since demonstrated the need for a new family for these parasites. We discovered a novel Enteromyxum in wild fish from Malaysia and herein describe the fourth species in the genus and erect a new family, the Enteromyxidae n. fam., to accommodate them. Enteromyxum caesio n. sp. is described infecting the tissues of the stomach in the redbelly yellowtail fusilier, Caesio cuning, from Malaysia. The new species is distinct from all others in the genus, as the myxospores although morphologically similar, are significantly smaller in size. Furthermore, small subunit ribosomal DNA sequence data reveal that E. caesio is <84% similar to others in the genus, but collectively they form a robust and discrete clade, the Enteromyxidae n. fam., which is placed as a sister taxon to other histozoic marine myxosporeans. In addition, we describe, using transmission electron microscopy, the epicellular stages of Enteromyxum fugu and show a scanning electron micrograph of a mature myxospore of E. caesio detailing the otherwise indistinct sutural line, features of the polar capsules and spore valve ridges. The Enteromyxidae n. fam. is a commercially important group of parasites infecting the gastrointestinal tract of marine fishes and the histozoic species can cause the disease enteromyxosis in intensive finfish aquaculture facilities. Epicellular and sloughed histozoic stages are responsible for fish-to-fish transmission in net pen aquaculture systems but actinospores from an annelid host are thought to be necessary for transmission to fish in the wild.
Introduction:Plasmodium knowlesi(P.knowlesi) is a zoonotic malaria parasite, transmitted between non-factors” or “individual factors” or “ecological factors” and “P.knowlesi” and “human” including human primate hosts by the Anopheles (An.) mosquitos, and causing spill-over infections in humans where the parasite, vector, host, and human converge
Methods:The search was done electronically toexplore for appropriate papers viaPubMed, and Science Direct for articles published up to March 2020, containing the words “factors associated” or “environmental synonyms and Medical Subject Heading (MeSH) terms. A total of 27 articles from PubMed Databases and 18 articles from Science Direct were selected to be assessed for eligibility. Out of it, a total of 13 articles were selected to be analysed.
Results:Host factors such as sex and age, as well as occupation as individual factors, while environmental factors such as rainfall and geographic elevation have some association with P.knowlesiinfection in humans. This zoonotic malaria poses unique challenges that will need to be addressed if all forms of malaria are to be eliminated based on the sustainable development goal (SDG)
Conclusion:This article highlights the importance of disease ecologies such as climate and landscape and human-environment interactions such as the land use patterns, such as agriculture or infrastructure activities) to reduce the further increase of cases and mortality globally due to P.knowlesiinfection. This review focuses mainly on the host and environmental factors that influence P.knowlesiMalaria Infection in Humans
Cucullanus sp. is a genus of nematode infecting Barbonymus schwanenfeldii. It is categorized under Family Cucullunidae. The genus Cucullanus sp consists of various species around the world, parasitizing freshwater, brackish-water or marine fishes. Cucullanus sp are mainly found in internal organs like stomach, intestine, kidney, and spleen. This parasitic organism can cause an economic impact, especially for animals with high market value, which are commercialized and used for human consumption. The objectives of this study are to study the morphological characteristics of Cucullanus sp and to identify genus of Cucullanus sp which are found on tinfoil barb, Barbonymus schwanenfeldii at Kenyir Lake, Terengganu. There is not enough data on Cucullanus sp on B. schwanenfeldii. Six samples of tinfoil barb were collected at Kenyir Lake from 25 to 27 October 2018. Each sample of fish was measured and recorded for length and weight using ruler and weighing balance respectively. The fish were examined at camping site at Lawit Resort, Kenyir Lake. The nematode species found were brought back to Health of Aquatic Organism laboratory. The abdominal and gastrointestinal tracts of the fishes were dissected and placed in petri dishes. The nematodes found were collected and observed under the dissecting microscope. The nematode specimen was placed on a glass slide with a drop of lactophenol and observed under the compound microscope fitted with dino-eye. The sample was later fixed with 70% alcohol. The morphological characteristic was drawn using camera lucida fitted to a compound microscope. (40X magnification). The picture of nematode was captured by using Advanced Research Microscope (Nikon Eclipse 80i) and measurements of the nematode was also made. Hence, the nematode found was identified as male Cucullanus sp.
Thelohanellus nikolskii, Achmerov, 1955 is a well-known myxozoan parasite of the common carp (Cyprinus carpio L.). Infection regularly manifests in numerous macroscopic cysts on the fins of two to three month-old pond-cultured carp fingerlings in July and August. However, a Thelohanellus infection is also common on the scales of two to three year-old common carp in ponds and natural waters in May and June. Based on myxospore morphology and tissue specificity, infection at both sites seems to be caused by the same species, namely T. nikolskii. This presumption was tested with molecular biological methods: SSU rDNA sequences of myxospores from fins of fingerlings and scales of older common carp were analysed and compared with each other and with related species available in GenBank. Sequence data revealed that the spores from the fins and scales represent the same species, T. nikolskii. Our study revealed a dichotomy in both infection site and time in T. nikolskii-infections: the fins of young carp are infected in Summer and Autumn, whereas the scales of older carp are infected in Spring. Myxosporean development of the species is well studied, little is known, however about the actinosporean stage of T. nikolskii. A previous experimental study suggests that aurantiactinomyxon actinospores of this species develop in Tubifex tubifex, Müller, 1774. The description included spore morphology but no genetic sequence data (Székely et al., 1998). We examined >9000 oligochaetes from Lake Balaton and Kis-Balaton Water Reservoire searching for the intraoligochaete developmental stage of myxozoans. Five oligochaete species were examined, Isochaetides michaelseni Lastochin, 1936, Branchiura sowerbyi Beddard, 1892, Nais sp., Müller, 1774, Dero sp. Müller, 1774 and Aelosoma sp. Ehrenberg, 1828. Morphometrics and SSU rDNA sequences were obtained for the released actinospores. Among them, from a single Nais sp., the sequence of an aurantiactinomyxon isolate corresponded to the myxospore sequences of T. nikolskii.
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.
The fish health status and parasitic infection in paddy fields are understudied in Borneo. This study was done to compare the prevalence and abundance of parasites on freshwater fishes in the upstream and downstream rivers of paddy fields. Parasite study on freshwater fishes was done by collecting live fish samples using ten minnow traps with baits at each site in Serian and Padawan, Sarawak, from October 2017 until March 2018. A total of 120 freshwater fishes were examined during this study period. Cold anaesthesia was applied on live samples prior to ectoparasite and endoparasite microscopic screening, which involved scraping of outer body mucous and removal of fish intestines, respectively. No ectoparasites were recovered from the fish samples. A total of 19 (15.83%) fishes from Cyprinids were infected with endoparasites. From these, 58 individuals of endoparasites were recovered. Two groups of parasites, namely Nematoda (Cucullanus sp.) and Trematoda (unidentified), were recovered from the fish intestines. From this study, there was a significant difference between the upstream fishes and downstream fishes in their endoparasite infection at both Triboh Village (p = 0.035) and Annah Rais Village (p = 1.445 × 10-6) using two samples t-test. The endoparasite abundance in fish was higher in the streams where there was less human disturbance. This study may serve as a baseline study on the parasitic infections of freshwater fishes in streams near paddy fields or other agricultural area in Sarawak.
Helminthiasis due to strongyles such as Haemonchus contortus, coccidiosis caused by Eimeria sp. and blood parasite diseases such as theileriosis by Theileria sp. have been reported to cause severe morbidity and mortality annually in small ruminants in Malaysia. The aims of this study were to investigate the prevalence of helminthiasis, coccidiosis and theileriosis and to determine the packed cell volume (PCV) value of small ruminants in Perak, Malaysia. Blood and faecal samples were obtained from a total of 175 animals from 7 small ruminant farms in Kampar, Larut Matang and Selama, Kuala Kangsar and Manjung districts in Perak; the samples were examined for parasitic infestations from April to July 2011. The results of this study show that H. contortus was found in 152 (86.86%) animals, Eimeria sp. was found in 162 (92.57%) animals and the blood protozoa Theileria sp. was found in 25 (14.30%) animals. The PCV values of all of these animals were recorded between 7% and 44%. A total of 42 (24%) animals were anaemic, with a PCV of less than 21%. Continuous monitoring of small ruminant farms will provide important information for assisting farmers with managing the spread of parasitic infections and maintaining the productivity of animals.
Fascioliasis, or trematode infestation, is an important disease caused by Fasciola hepatica and Fasciola gigantica. Both species are hepatic parasites that affect humans. We have examined the zoonotic aspects of fascioliasis. A total of 80 fresh liver samples were collected from 67 Kedah-Kelantan crossbred cattle and 13 Murrah buffalo at 4 local abattoirs in Perak, Malaysia. The samples were examined macroscopically to detect the presence of Fasciola spp. The results show 7.50% (6 of 80) of the animals were diagnosed with fascioliasis. Overall, 7.46% (5 of 67) and 7.69% (1 of 13) of cattle and buffalo samples were positive, respectively. There were only F. gigantica species identified in the samples. Our findings suggest that precautions should be taken because the disease has a zoonotic impact on public health.
A total of six wild broodstocks of tiger prawns, Penaeus monodon, were found positive for White Spot Virus (WSV) with an IQ2000 detection kit. Using histopathology, the intranuclear inclusion of haemocyte due to WSV infection was observed in the epithelium cells of the antennal gland, stomach and gills. This result confirmed that the wild broodstocks were positive with WSV without showing any white spot. Additionally, histopathological examination also revealed an accumulation of haemocytes around the hepatopancreatic tubules resulting from bacterial infection. Encapsulation and nodule formation, as well as related necrosis, were also observed around the hepatopancreatic tubules infected with a metazoan parasite. Encysted tylocephalum larval cestodes were observed in the hepatopancreas, with haemocytic aggregation being observed around the infected tubules. These findings showed some bacterial and parasitic infections which, in addition to the viral infection itself, could contribute to the 80% mortality rate in wild broodstocks infected with WSV.
Sarcosporidiosis is a disease caused by intracellular protozoan parasites, namely, Sarcocystis spp. In pigs, three species of Sarcocystis spp. have been recognised, including Sarcocystis meischeriana, Sarcocystis porcifelis and Sarcocystis suihominis. The aim of this study is to determine the prevalence of muscular sarcosporidiosis in pigs using the pepsin digestion technique. A total of 150 fresh heart, oesophagus and thigh muscle samples from 50 Yorkshire and Landrace pigs were collected from two local abattoirs in Perak from May to August 2014. All the fresh muscle samples were thoroughly examined for macrocyst-forming Sarcocystis spp. and processed using the peptic digestion technique to detect bradyzoites. The results from the muscle samples showed that 58% (29 out of 50) of the pigs were positive for Sarcocystis spp. These findings highlight the importance of implementing stringent measures for screening pigs in abattoirs for Sarcocystis spp. infection because this infection in pigs is a public health concern.
Intestinal parasitic infections are one of the most common causes of human diseases that result in serious health and economic issues in many developing and developed countries. Raw vegetables and fruits play an important role in transmitting parasites to humans. Hence, the aim of this study was to investigate the parasitological contamination of select commonly consumed local leafy vegetables and fruits in Kuantan, Malaysia. One kilogram of locally consumed raw vegetables and fruits were collected randomly from the Kuantan wet market (Pasar Tani) during the monsoon season (November 2014-January 2015) and the dry season (February 2015-April 2015). A standard wet mount procedure and modified Ziehl-Neelsen staining were used for the detection of parasites. In the present study, the examination of vegetables revealed five different parasite species. The vegetable samples collected from Kuantan's wet market were positive for both helminthes and protozoa. However, the fruits samples were negative for parasitic contamination. Pegaga was the most contaminated leafy vegetable in this study, and Strongyloides was the parasite found most frequently. Furthermore, there was a high diversity in the type of parasites observed during the dry season compared to the monsoon season. Therefore, further action should be taken to reduce the occurrence of parasitic contamination in vegetables by implementing the principles of good agricultural practice and improving water treatment efficacy.