MyMedR

Displaying publications 1 - 20 of 30 in total

Abstract:

Sort:

Fulltext Is there a risk of suburban transmission of malaria in Selangor, Malaysia?

Braima KA, Sum JS, Ghazali AR, Muslimin M, Jeffery J, Lee WC, et al.

PLoS One, 2013;8(10):e77924.
PMID: 24194901 DOI: 10.1371/journal.pone.0077924

BACKGROUND: The suburban transmission of malaria in Selangor, Malaysia's most developed and populous state still remains a concern for public health in this region. Despite much successful control efforts directed at its reduction, sporadic cases, mostly brought in by foreigners have continued to occur. In addition, cases of simian malaria caused by Plasmodium knowlesi, some with fatal outcome have caused grave concern to health workers. The aim of this study was to investigate the possibility of local malaria transmission in suburban regions of Selangor, which are adjacent to secondary rainforests.
FINDINGS: A malaria survey spanning 7 years (2006 - 2012) was conducted in Selangor. A total of 1623 laboratory confirmed malaria cases were reported from Selangor's nine districts. While 72.6% of these cases (1178/1623) were attributed to imported malaria (cases originating from other countries), 25.5% (414/1623) were local cases and 1.9% (31/1623) were considered as relapse and unclassified cases combined. In this study, the most prevalent infection was P. vivax (1239 cases, prevalence 76.3%) followed by P. falciparum (211, 13.0%), P. knowlesi (75, 4.6%), P. malariae (71, 4.4%) and P. ovale (1, 0.06%). Mixed infections comprising of P. vivax and P. falciparum were confirmed (26, 1.6%). Entomological surveys targeting the residences of malaria patients' showed that the most commonly trapped Anopheles species was An. maculatus. No oocysts or sporozoites were found in the An. maculatus collected. Nevertheless, the possibility of An. maculatus being the malaria vector in the investigated locations was high due to its persistent occurrence in these areas.
CONCLUSIONS: Malaria cases reported in this study were mostly imported cases. However the co-existence of local cases and potential Plasmodium spp. vectors should be cause for concern. The results of this survey reflect the need of maintaining closely monitored malaria control programs and continuous extensive malaria surveillance in Peninsula Malaysia.

Matched MeSH terms: Monkey Diseases/epidemiology*
Helminth parasites occurrence in wild proboscis monkeys (Nasalis larvatus), endemic primates to Borneo Island

Adrus M, Zainuddin R, Ahmad Khairi NH, Ahamad M, Abdullah MT

J Med Primatol, 2019 12;48(6):357-363.
PMID: 31486088 DOI: 10.1111/jmp.12437

BACKGROUND: Nasalis larvatus are well-known attraction for tourists in the mangrove forest of Bako National Park (BNP). Little is known regarding the infestation of helminth parasites in proboscis monkeys. Therefore, the objectives of this study are to determine the prevalence species of major helminth parasites of public health importance in proboscis monkeys in BNP.
METHODS: A total of 65 faecal samples screened for helminth parasites via sodium nitrate floatation and faecal sedimentation techniques.
RESULTS: A total of 14 helminth parasite species comprising of eight genera of nematodes, two species of cestodes and two trematodes were identified. Eggs of Trichuris trichiura were the most frequently encountered in proboscis monkeys.
CONCLUSION: This is the first survey on the fauna of helminth parasites of proboscis monkeys living in mangrove forests, and therefore, it implies the important baseline information that increases our current knowledge for future research regarding parasite-host ecology in primates.

Matched MeSH terms: Monkey Diseases/epidemiology*
Gastrointestinal parasites of zoonotic importance observed in the wild, urban, and captive populations of non-human primates in Malaysia

Adrus M, Zainudin R, Ahamad M, Jayasilan MA, Abdullah MT

J Med Primatol, 2019 02;48(1):22-31.
PMID: 30370934 DOI: 10.1111/jmp.12389

BACKGROUND: A study was undertaken to determine gastrointestinal (GI) parasites commonly found in Malaysia's non-human primates (NHP) living in three different types of populations (wild, urban, and captive) and the basis of major GI parasites of zoonotic importance.
METHODS: A total of 308 samples was collected and microscopically screened from the NHP in the wild (n = 163), urban (n = 76), and captive (n = 69) populations. The samples were taken from 12 species of local NHPs.
RESULTS: At least, 44 species of GI parasites comprising of protozoans (seven species), nematodes (26 species), cestodes (five species), trematodes (five species), and pentastomida (one species) were detected. There were no significant differences for the overall prevalence and no great differences in GI parasite species among the wild, urban, and captive NHP populations.
CONCLUSION: The most common GI parasite was Ascaris spp. (49.7%), followed by Oesophagostomum spp. (26.9%), and 31 species discovered in this study are of known public health importance.

Matched MeSH terms: Monkey Diseases/epidemiology*
An epizootic of measles in captive silvered leaf-monkeys (Presbytis cristatus) in Malaysia

Montrey RD, Huxsoll DL, Hildebrandt PK, Booth BW, Arimbalam S

Lab. Anim. Sci., 1980 Aug;30(4 Pt 1):694-7.
PMID: 7421117

An epizootic of measles occurred in a group of 31 silvered leaf-monkeys (Presbytis cristatus) that had been in captivity for 4-12 months. Twenty-four of the monkeys exhibited a maculopapular rash that persisted for 6-9 days. A serous to mucopurulent nasal discharge and conjunctivitis were seen in some animals. Eight monkeys died during the epizootic; however, their deaths could not be directly attributed to measles. Serum samples from the surviving monkeys collected 1-2 months prior to, and 5 weeks after, the epizootic were examined by the complement-fixation and hemagglutination-inhibition tests for antibodies to measles virus. The preepizootic complement-fixation titers were all less than 1:4 and hemagglutination-inhibition titers, less than 1:10. The postepizootic complement-fixation titers in 21 of 23 surviving monkeys ranged from 1:8 to 1:128, and hemagglutination-inhibition titers in 22 of 23 monkeys ranged from 1:40 to 1:80 or greater.

Matched MeSH terms: Monkey Diseases/epidemiology*
Plasmodium inui-like infection producing a presumably fatal illness in a leaf monkey Presbytis johnii--a previously undescribed host

Das SK, Strauss JM, Chee CT

Med J Malaya, 1966 Jun;20(4):323.
PMID: 4224342
Matched MeSH terms: Monkey Diseases/epidemiology*
Occurrence of gastrointestinal nematodes in captive nonhuman primates at Matang Wildlife Centre, Sarawak

Teo SZ, Tuen AA, Madinah A, Aban S, Chong YL

Trop Biomed, 2019 Sep 01;36(3):594-603.
PMID: 33597481

Gastrointestinal nematodes can cause assorted health problems to human and other primates. The status of gastrointestinal nematodes in non-human primates remained less documented in Malaysia. This study aimed to determine the occurrence of gastrointestinal nematodes recovered from the fecal samples of captive non-human primates at the Matang Wildlife Centre (MWC), Sarawak. Fresh fecal samples were collected from 60 non-human primates of six species (i.e. Orangutan, Bornean gibbon, Silvered Leaf monkey, Slow loris, Pig-tailed macaque, and Long-tailed macaque) and processed using simple fecal floatation method and fecal sedimentation method. This study shows high prevalence of nematode infection (>=50%) and co-infection (22 from 45 infected individuals) in all species of captive non-human primates found in MWC, except one individual of young Silvered Leaf monkey was negative for nematode. From these, eight genera of 11 species and one unknown nematode larvae were recovered and among them Oesophagostomum sp., Ascaris sp., and Strongyloides sp. were the most common nematodes infecting the non-human primates. All the Bornean gibbon (n=7) were found to be infected with nematodes. Moreover, Long-tailed macaques at the centre were heavily infected by Ascaris sp. (number of total count, nt = 2132; total mean abundance, MA=113.70). This is the first report of high prevalence nematode infection on multiple species of captive non-human primates in a wildlife centre located in Sarawak. Some of the nematodes are of zoonotic potential. This information is important for health care management, both in-situ and ex-situ conservations of captive and free-ranging nonhuman primates.

Matched MeSH terms: Monkey Diseases/epidemiology
The simian malarias: zoonoses, anthroponoses, or both?

Coatney GR

Am J Trop Med Hyg, 1971 Nov;20(6):795-803.
PMID: 5002245
Matched MeSH terms: Monkey Diseases/epidemiology
Simian malarias in man: facts, implications, and predictions

Coatney GR

Am J Trop Med Hyg, 1968 Mar;17(2):147-55.
PMID: 4869108
Matched MeSH terms: Monkey Diseases/epidemiology
Fulltext Admixture in Humans of Two Divergent Plasmodium knowlesi Populations Associated with Different Macaque Host Species

Divis PC, Singh B, Anderios F, Hisam S, Matusop A, Kocken CH, et al.

PLoS Pathog, 2015 May;11(5):e1004888.
PMID: 26020959 DOI: 10.1371/journal.ppat.1004888

Human malaria parasite species were originally acquired from other primate hosts and subsequently became endemic, then spread throughout large parts of the world. A major zoonosis is now occurring with Plasmodium knowlesi from macaques in Southeast Asia, with a recent acceleration in numbers of reported cases particularly in Malaysia. To investigate the parasite population genetics, we developed sensitive and species-specific microsatellite genotyping protocols and applied these to analysis of samples from 10 sites covering a range of >1,600 km within which most cases have occurred. Genotypic analyses of 599 P. knowlesi infections (552 in humans and 47 in wild macaques) at 10 highly polymorphic loci provide radical new insights on the emergence. Parasites from sympatric long-tailed macaques (Macaca fascicularis) and pig-tailed macaques (M. nemestrina) were very highly differentiated (FST = 0.22, and K-means clustering confirmed two host-associated subpopulations). Approximately two thirds of human P. knowlesi infections were of the long-tailed macaque type (Cluster 1), and one third were of the pig-tailed-macaque type (Cluster 2), with relative proportions varying across the different sites. Among the samples from humans, there was significant indication of genetic isolation by geographical distance overall and within Cluster 1 alone. Across the different sites, the level of multi-locus linkage disequilibrium correlated with the degree of local admixture of the two different clusters. The widespread occurrence of both types of P. knowlesi in humans enhances the potential for parasite adaptation in this zoonotic system.

Matched MeSH terms: Monkey Diseases/epidemiology*
Fulltext Macacine Herpesvirus 1 in Long-Tailed Macaques, Malaysia, 2009-2011

Lee MH, Rostal MK, Hughes T, Sitam F, Lee CY, Japning J, et al.

Emerg Infect Dis, 2015 Jul;21(7):1107-13.
PMID: 26080081 DOI: 10.3201/eid2107.140162

Macacine herpesvirus 1 (MaHV1; B virus) naturally infects macaques (Macaca spp.) and can cause fatal encephalitis in humans. In Peninsular Malaysia, wild macaques are abundant, and translocation is used to mitigate human-macaque conflict. Most adult macaques are infected with MaHV1, although the risk for transmission to persons who handle them during capture and translocation is unknown. We investigated MaHV1 shedding among 392 long-tailed macaques (M. fascicularis) after capture and translocation by the Department of Wildlife and National Parks in Peninsular Malaysia, during 2009-2011. For detection of MaHV1 DNA, PCR was performed on urogenital and oropharyngeal swab samples. Overall, 39% of macaques were shedding MaHV1 DNA; rates of DNA detection did not differ between sample types. This study demonstrates that MaHV1 was shed by a substantial proportion of macaques after capture and transport and suggests that persons handling macaques under these circumstances might be at risk for exposure to MaHV1.

Matched MeSH terms: Monkey Diseases/epidemiology
Serological evidence of infection with Tana and Yaba pox viruses among several species of monkey

Downie AW

J Hyg (Lond), 1974 Apr;72(2):245-50.
PMID: 4362411

Sera from cynomolgus monkeys from Malaysia, from Indian rhesus monkeys, from various species of monkeys from Africa and from South America have been examined for neutralizing antibody to Tanapox and Yaba viruses. No antibody was found to either virus in the sera of rhesus monkeys or South American monkeys. A certain proportion of sera from cynomolgus monkeys and various species of African monkey showed antibody to one or other of the viruses, but few of the positive sera showed antibody to both. The results would seem to suggest that infection with the two viruses is endemic in African and Malaysian monkeys but does not occur or is very rare in Indian rhesus and New World monkeys.

Matched MeSH terms: Monkey Diseases/epidemiology*
Fulltext Predicting the geographical distributions of the macaque hosts and mosquito vectors of Plasmodium knowlesi malaria in forested and non-forested areas

Moyes CL, Shearer FM, Huang Z, Wiebe A, Gibson HS, Nijman V, et al.

Parasit Vectors, 2016 Apr 28;9:242.
PMID: 27125995 DOI: 10.1186/s13071-016-1527-0

BACKGROUND: Plasmodium knowlesi is a zoonotic pathogen, transmitted among macaques and to humans by anopheline mosquitoes. Information on P. knowlesi malaria is lacking in most regions so the first step to understand the geographical distribution of disease risk is to define the distributions of the reservoir and vector species.
METHODS: We used macaque and mosquito species presence data, background data that captured sampling bias in the presence data, a boosted regression tree model and environmental datasets, including annual data for land classes, to predict the distributions of each vector and host species. We then compared the predicted distribution of each species with cover of each land class.
RESULTS: Fine-scale distribution maps were generated for three macaque host species (Macaca fascicularis, M. nemestrina and M. leonina) and two mosquito vector complexes (the Dirus Complex and the Leucosphyrus Complex). The Leucosphyrus Complex was predicted to occur in areas with disturbed, but not intact, forest cover (> 60% tree cover) whereas the Dirus Complex was predicted to occur in areas with 10-100% tree cover as well as vegetation mosaics and cropland. Of the macaque species, M. nemestrina was mainly predicted to occur in forested areas whereas M. fascicularis was predicted to occur in vegetation mosaics, cropland, wetland and urban areas in addition to forested areas.
CONCLUSIONS: The predicted M. fascicularis distribution encompassed a wide range of habitats where humans are found. This is of most significance in the northern part of its range where members of the Dirus Complex are the main P. knowlesi vectors because these mosquitoes were also predicted to occur in a wider range of habitats. Our results support the hypothesis that conversion of intact forest into disturbed forest (for example plantations or timber concessions), or the creation of vegetation mosaics, will increase the probability that members of the Leucosphyrus Complex occur at these locations, as well as bringing humans into these areas. An explicit analysis of disease risk itself using infection data is required to explore this further. The species distributions generated here can now be included in future analyses of P. knowlesi infection risk.

Matched MeSH terms: Monkey Diseases/epidemiology
[Incidence of diarrhea and antibiotic therapy in cynomolgus monkeys imported for medical use (author's transl)]

Takasaka M, Morota S, Kasono T, Abe M, Honjo S

Jikken Dobutsu, 1973 Jul;22(3):227-36.
PMID: 4204642
Matched MeSH terms: Monkey Diseases/epidemiology*
Natural Plasmodium infection in wild macaques of three states in peninsular Malaysia

Amir A, Shahari S, Liew JWK, de Silva JR, Khan MB, Lai MY, et al.

Acta Trop, 2020 Nov;211:105596.
PMID: 32589995 DOI: 10.1016/j.actatropica.2020.105596

Zoonotic cases of Plasmodium knowlesi account for most malaria cases in Malaysia, and humans infected with P. cynomolgi, another parasite of macaques have recently been reported in Sarawak. To date the epidemiology of malaria in its natural Macaca reservoir hosts remains little investigated. In this study we surveyed the prevalence of simian malaria in wild macaques of three states in Peninsular Malaysia, namely Pahang, Perak and Johor using blood samples from 103 wild macaques (collected by the Department of Wildlife and National Parks Peninsular Malaysia) subjected to microscopic examination and nested PCR targeting the Plasmodium small subunit ribosomal RNA gene. As expected, PCR analysis yielded significantly higher prevalence (64/103) as compared to microscopic examination (27/103). No relationship between the age and/or sex of the macaques with the parasitaemia and the Plasmodium species infecting the macaques could be identified. Wild macaques in Pahang had the highest prevalence of Plasmodium parasites (89.7%), followed by those of Perak (69.2%) and Johor (28.9%). Plasmodium inui and P. cynomolgi were the two most prevalent species infecting the macaques from all three states. Half of the macaques (33/64) harboured two or more Plasmodium species. These data provide a baseline survey, which should be extended by further longitudinal investigations that should be associated with studies on the bionomics of the anopheline vectors. This information will allow an accurate evaluation of the risk of zoonotic transmission to humans, and to elaborate effective strategies to control simian malaria.

Matched MeSH terms: Monkey Diseases/epidemiology
Fulltext Phylogeographic Evidence for 2 Genetically Distinct Zoonotic Plasmodium knowlesi Parasites, Malaysia

Yusof R, Ahmed MA, Jelip J, Ngian HU, Mustakim S, Hussin HM, et al.

Emerg Infect Dis, 2016 Aug;22(8):1371-80.
PMID: 27433965 DOI: 10.3201/eid2208.151885

Infections of humans with the zoonotic simian malaria parasite Plasmodium knowlesi occur throughout Southeast Asia, although most cases have occurred in Malaysia, where P. knowlesi is now the dominant malaria species. This apparently skewed distribution prompted an investigation of the phylogeography of this parasite in 2 geographically separated regions of Malaysia, Peninsular Malaysia and Malaysian Borneo. We investigated samples collected from humans and macaques in these regions. Haplotype network analyses of sequences from 2 P. knowlesi genes, type A small subunit ribosomal 18S RNA and cytochrome c oxidase subunit I, showed 2 genetically distinct divergent clusters, 1 from each of the 2 regions of Malaysia. We propose that these parasites represent 2 distinct P. knowlesi types that independently became zoonotic. These types would have evolved after the sea-level rise at the end of the last ice age, which separated Malaysian Borneo from Peninsular Malaysia.

Matched MeSH terms: Monkey Diseases/epidemiology
Fulltext Human Plasmodium knowlesi infections in South-East Asian countries

Zaw MT, Lin Z

J Microbiol Immunol Infect, 2019 Oct;52(5):679-684.
PMID: 31320238 DOI: 10.1016/j.jmii.2019.05.012

Plasmodium knowlesi is now regarded as the fifth malaria parasite causing human malaria as it is widely distributed in South-East Asian countries especially east Malaysia where two Malaysian states namely Sabah and Sarawak are situated. In 2004, Polymerase Chain Reaction (PCR) was applied for diagnosing knowlesi malaria in the Kapit Division of Sarawak, Malaysia, so that human P. knowlesi infections could be detected correctly while blood film microscopy diagnosed incorrectly as Plasmodium malariae. This parasite is transmitted from simian hosts to humans via Anopheles vectors. Indonesia is the another country in South East Asia where knowlesi malaria is moderately prevalent. In the last decade, Sarawak and Sabah, the two states of east Malaysia became the target of P. knowlesi research due to prevalence of cases with occasional fatal infections. The host species of P. knowlesi are three macaque species namely Macaca fascicularis, Macaca nemestrina and Macaca leonina while the vector species are the Leucosphyrus Complex and the Dirus Complex of the Leucophyrus Group of Anopheles mosquitoes. Rapid diagnostic tests (RDT) are non-existent for knowlesi malaria although timely treatment is necessary for preventing complications, fatality and drug resistance. Development of RDT is essential in dealing with P. knowlesi infections in poor rural healthcare services. Genetic studies of the parasite on possibility of human-to-human transmission of P. knowlesi were recommended for further studies.

Matched MeSH terms: Monkey Diseases/epidemiology
Prevalence of parasites in working pig-tailed Macaques (Macaca nemestrina) in Kelantan, Malaysia

Choong SS, Mimi Armiladiana M, Ruhil HH, Peng TL

J Med Primatol, 2019 08;48(4):207-210.
PMID: 31025372 DOI: 10.1111/jmp.12416

BACKGROUND: Coconut is an important commodity in Kelantan, and pig-tailed macaques (Macaca nemestrina) have been traditionally used for coconut-plucking for over a century. Most of these animals were sourced from the wild population, and the parasitic status of these macaques is unknown, plus the impacts caused by these parasites are usually underestimated by the owners.
METHODS: A total of 30 macaques were sampled for blood, faeces and hair plucks to detect parasite.
RESULTS: Out of 21 faecal samples examined, 11 (52%) were determined positive for one or more gastrointestinal parasites, namely Trichostrongylus spp., Strongyloides spp., Anatrichosoma spp., Capillaria spp., Trichuris spp. and Paramphisotomum spp. Filaria was detected in one (3%) of the blood samples. For ectoparasites, only lice, Pedicinus sp., were found in 9 (30%) macaques.
CONCLUSIONS: It is imperative that the parasitic status of these animals be determined so that necessary actions and preventive measures can be implemented to prevent zoonotic transmissions.

Matched MeSH terms: Monkey Diseases/epidemiology*
Malaria, arbovirus and hepatitis infections in Macaca fascicularis from Malaysia

Le Bras J, Larouze B, Geniteau M, Andrieu B, Dazza MC, Rodhain F

Lab. Anim., 1984 Jan;18(1):61-4.
PMID: 10628790

Naturally occurring malaria, arbovirus infection and hepatitis in monkeys can be a hazard for the investigator and might interfere with the outcome of experiments. 63 young adult Macaca fascicularis from Malaysia were screened for these infections. About 1 year after their arrival in France, parasitaemia due to Plasmodium spp., was present in 6.4% of the animals and specific antibodies in 55.5%. 19 of 35 initially positive monkeys were tested again 2 years later. Parasitaemia was found in 1 of 4 monkeys and antibodies in 11 of 19 monkeys which were initially positive. 9 of the monkeys initially tested had low titres of antibodies to the Flavivirus genus. All animals were negative for the hepatitis B surface antigen and anti-HBc. The prevalence of IgG antibodies against hepatitis A was 46.0%. The implications in terms of control are discussed.

Matched MeSH terms: Monkey Diseases/epidemiology*
Fulltext Little Evidence of Zika Virus Infection in Wild Long-Tailed Macaques, Peninsular Malaysia

Chua CL, Chan YF, Andu ESGS, Rovie-Ryan JJ, Sitam FT, Verasahib K, et al.

Emerg Infect Dis, 2019 02;25(2):374-376.
PMID: 30666941 DOI: 10.3201/eid2502.180258

We tested a sample of 234 wild long-tailed macaques (Macaca fascicularis) trapped in Peninsular Malaysia in 2009, 2010, and 2016 for Zika virus RNA and antibodies. None were positive for RNA, and only 1.3% were seropositive for neutralizing antibodies. Long-tailed macaques are unlikely to be reservoirs for Zika virus in Malaysia.

Matched MeSH terms: Monkey Diseases/epidemiology*
Fulltext Plasmodium knowlesi: reservoir hosts and tracking the emergence in humans and macaques

Lee KS, Divis PC, Zakaria SK, Matusop A, Julin RA, Conway DJ, et al.

PLoS Pathog, 2011 Apr;7(4):e1002015.
PMID: 21490952 DOI: 10.1371/journal.ppat.1002015

Plasmodium knowlesi, a malaria parasite originally thought to be restricted to macaques in Southeast Asia, has recently been recognized as a significant cause of human malaria. Unlike the benign and morphologically similar P. malariae, these parasites can lead to fatal infections. Malaria parasites, including P. knowlesi, have not yet been detected in macaques of the Kapit Division of Malaysian Borneo, where the majority of human knowlesi malaria cases have been reported. In order to extend our understanding of the epidemiology and evolutionary history of P. knowlesi, we examined 108 wild macaques for malaria parasites and sequenced the circumsporozoite protein (csp) gene and mitochondrial (mt) DNA of P. knowlesi isolates derived from macaques and humans. We detected five species of Plasmodium (P. knowlesi, P. inui, P. cynomolgi, P. fieldi and P. coatneyi) in the long-tailed and pig-tailed macaques, and an extremely high prevalence of P. inui and P. knowlesi. Macaques had a higher number of P. knowlesi genotypes per infection than humans, and some diverse alleles of the P. knowlesi csp gene and certain mtDNA haplotypes were shared between both hosts. Analyses of DNA sequence data indicate that there are no mtDNA lineages associated exclusively with either host. Furthermore, our analyses of the mtDNA data reveal that P. knowlesi is derived from an ancestral parasite population that existed prior to human settlement in Southeast Asia, and underwent significant population expansion approximately 30,000-40,000 years ago. Our results indicate that human infections with P. knowlesi are not newly emergent in Southeast Asia and that knowlesi malaria is primarily a zoonosis with wild macaques as the reservoir hosts. However, ongoing ecological changes resulting from deforestation, with an associated increase in the human population, could enable this pathogenic species of Plasmodium to switch to humans as the preferred host.

Matched MeSH terms: Monkey Diseases/epidemiology*

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links