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Fulltext Evidence for Nipah virus recrudescence and serological patterns of captive Pteropus vampyrus

Sohayati AR, Hassan L, Sharifah SH, Lazarus K, Zaini CM, Epstein JH, et al.

Epidemiol Infect, 2011 Oct;139(10):1570-9.
PMID: 21524339 DOI: 10.1017/S0950268811000550

This study aimed to describe the transmission dynamics, the serological and virus excretion patterns of Nipah virus (NiV) in Pteropus vampyrus bats. Bats in captivity were sampled every 7-21 days over a 1-year period. The data revealed five NiV serological patterns categorized as high and low positives, waning, decreasing and increasing, and negative in these individuals. The findings strongly suggest that NiV circulates in wild bat populations and that antibody could be maintained for long periods. The study also found that pup and juvenile bats from seropositive dams tested seropositive, indicating that maternal antibodies against NiV are transmitted passively, and in this study population may last up to 14 months. NiV was isolated from the urine of one bat, and within a few weeks, two other seronegative bats seroconverted. Based on the temporal cluster of seroconversion, we strongly believe that the NiV isolated was recrudesced and then transmitted horizontally between bats during the study period.

Matched MeSH terms: Chiroptera/virology*; Henipavirus Infections/virology
Genetic variability and evolutionary analyses of the coat protein gene of Tomato mosaic virus

Rangel EA, Alfaro-Fernández A, Font-San-Ambrosio MI, Luis-Arteaga M, Rubio L

Virus Genes, 2011 Dec;43(3):435-8.
PMID: 21881940 DOI: 10.1007/s11262-011-0651-3

Tomato mosaic virus (ToMV), a member of the genus Tobamovirus, infects several ornamental and horticultural crops worldwide. In this study, the nucleotide sequences of the coat protein gene of worldwide ToMV isolates were analyzed to estimate the genetic structure and diversity of this virus and the involved evolutionary forces. The phylogenetic analysis showed three clades with high bootstrap support: Clade I contained three ToMV isolates from Brazil collected from pepper, Clade II comprised one Brazilian ToMV isolate from pepper, and Clade III was composed of ToMV isolates collected from different plant hosts (pepper, tomato, eggplant, lilac, camellia, dogwood, red spruce, etc.) and water (from melting ice, lakes and streams) from different countries: USA, Brazil, Korea, Germany, Spain, Denmark (Greenland), China, Taiwan, Malaysia, Iran, and Kazakhstan. With the exception of Brazil, nucleotide diversity within and between different geographic regions was very low, although statistical analyses suggested some gene flow between most of these regions. Our analyses also suggested a strong negative selection which could have contributed to the genetic stability of ToMV.

Matched MeSH terms: Plant Diseases/virology*; Lycopersicon esculentum/virology
Fulltext Molecular identification of adenovirus causing respiratory tract infection in pediatric patients at the University of Malaya Medical Center

Abd-Jamil J, Teoh BT, Hassan EH, Roslan N, Abubakar S

BMC Pediatr, 2010;10:46.
PMID: 20594359 DOI: 10.1186/1471-2431-10-46

There are at least 51 adenovirus serotypes (AdV) known to cause human infections. The prevalence of the different human AdV (HAdV) serotypes varies among different regions. Presently, there are no reports of the prevalent HAdV types found in Malaysia. The present study was undertaken to identify the HAdV types associated primarily with respiratory tract infections (RTI) of young children in Malaysia.

Matched MeSH terms: Adenovirus Infections, Human/virology*; Respiratory Tract Infections/virology*
Crude protein extraction protocol for phage N15 protelomerase in vitro enzymatic assays

Chen Q, Narayanan K

Anal Biochem, 2011 Jul 1;414(1):169-71.
PMID: 21396906 DOI: 10.1016/j.ab.2011.03.006

The phage N15 protelomerase enzyme (TelN) is essential for the replication of its genome by resolution of its telRL domain, located within a telomerase occupancy site (tos), into hairpin telomeres. Isolation of TelN for in vitro processing of tos, however, is a highly complex process, requiring multiple purification steps. In this study a simplified protocol for crude total protein extraction is described that retains the tos-cleaving activity of TelN for at least 4 weeks, greatly simplifying in vitro testing of its activity. This protocol may be extended for functional analysis of other phage and bacterial proteins, particularly DNA-processing enzymes.

Matched MeSH terms: Bacteria/virology; Escherichia coli/virology
Fulltext Pandemic influenza A (H1N1) 2009 in Malaysia--the next phase

Sam IC, Abu Bakar S

Med J Malaysia, 2009 Jun;64(2):105-7.
PMID: 20058566

In recent years, zoonotic RNA viruses such as Nipah, SARS coronavirus, avian influenza (H5N1) and Chikungunya have emerged with global impact. The latest has now been designated by World Health Organization (WHO) as pandemic (H1N1) 2009 virus. It was first reported as an outbreak in Mexico in April, and has now caused the first influenza pandemic since 1968. By July 11, 2009, there were 105,304 confirmed cases and 463 deaths in 143 countries, including 627 cases in Malaysia1 . The rapid spread of the disease has been matched by the speed of dissemination of information and protocols, co-ordinated by WHO. The experiences of SARS and H5N1 have been enormously beneficial in preparing the world for a pandemic.

Matched MeSH terms: Influenza, Human/virology; Swine/virology
Fulltext Transmission of human infection with Nipah virus

Luby SP, Gurley ES, Hossain MJ

Clin Infect Dis, 2009 Dec 1;49(11):1743-8.
PMID: 19886791 DOI: 10.1086/647951

Nipah virus (NiV) is a paramyxovirus whose reservoir host is fruit bats of the genus Pteropus. Occasionally the virus is introduced into human populations and causes severe illness characterized by encephalitis or respiratory disease. The first outbreak of NiV was recognized in Malaysia, but 8 outbreaks have been reported from Bangladesh since 2001. The primary pathways of transmission from bats to people in Bangladesh are through contamination of raw date palm sap by bats with subsequent consumption by humans and through infection of domestic animals (cattle, pigs, and goats), presumably from consumption of food contaminated with bat saliva or urine with subsequent transmission to people. Approximately one-half of recognized Nipah case patients in Bangladesh developed their disease following person-to-person transmission of the virus. Efforts to prevent transmission should focus on decreasing bat access to date palm sap and reducing family members' and friends' exposure to infected patients' saliva.

Matched MeSH terms: Chiroptera/virology; Henipavirus Infections/virology
[Identification and sequence analysis of E gene of Dengue virus type 2 strain isolated from patient serum in Shenzhen]

Yang F, He JF, Xian HX, Zhang HL, He YQ, Yang H, et al.

Zhonghua Yu Fang Yi Xue Za Zhi, 2009 Sep;43(9):798-802.
PMID: 20137564

To isolate and identify the pathogen of Dengue fever from Shenzhen city in 2005 - 2006, and to analyze the molecular characteristics of the isolated Dengue virus strain as well as to explore its possible origin.

Matched MeSH terms: Aedes/virology; Dengue/virology*
An optimized method for extraction and detection of Coconut cadang-cadang viroid(CCCVd) from oil palm

Mohammadi MR, Vadamalai G, Joseph H

Commun. Agric. Appl. Biol. Sci., 2010;75(4):777-81.
PMID: 21534490

Coconut cadong-cadong viroid (CCCVd) causes the Lethal cadang-cadang disease of coconut palms in the Philippines and it is recently reported to be associated with the orange spotting disease on oil palm in Malaysia. The low concentration of the viroid RNA in oil palm as well as the high content of polyphenols and polysaccharides in this plant which interfere with the purification steps makes it difficult to extract and detect this viroid from oil palm. A previously described method was modified and optimized for extraction and detection of CCCVd from infected oil palms. Briefly, 7 g of leaf material was homogenized in a mortar or a blender using liquid nitrogen. 10 ml of extraction buffer (100 mM Tris-HCl pH 7.5, 100 mM NaCl, 10 mM EDTA) along with 100 mM 2-mercaptoethanol and 10 ml water saturated phenol was added to the frozen powder. After centrifuging at 4 degrees C, 4000 g for 30 min, the aqueous phase was extracted once more with phenol then once with chloroform-isoamyl alcohol (24:1). After adding sodium acetate, pH 5.6 to 200 mM, the mixture was precipitated with 2.5 vol ethanol overnight in -20 freezer and then the pellet was washed with 70% ethanol and air-dried. One milliliter of 8 M LiCl was added to the dried pellet and after shaking overnight at 4 degrees C and another centrifugation step the supernatant was collected and precipitated again with ethanol and then the resulting pellet was washed and air-dried. To carry out northern blotting, samples equivalent to 40 g of plant tissue were mixed with formamide buffer and loaded onto a 12% polyacrylamide gel containing 7 M urea and after separation by electrophoresis, were electroblotted onto membrane and fixed by UV cross-linking. Pre-hybridization and hybridization using hybridization buffer (50% formamide, 25%SSPE, 0.1% Ficol and PVP, 0.1 % SDS, 0.02 % DNA (5mg/ml)) was carried out at 45 degrees C for 90 min and 16 h, respectively followed by two low stringency washes (0.5 X SSC, 0.1% SDS, at room temperature for 5 min) and one high stringency wash (0.1X SSC, 0.1% SDS at 60 degrees C for 1 hour). In vitro synthesized DIG-labeled full-length CCCVd(-) RNA probe was used in hybridization step. DIG Nucleic Acid Detection Kit (Roche) instructions were followed for detection procedure and as a result the blue bands corresponding to the position of the viroid were appeared on the membrane. The result of this study showed the ability of DIG labeled probe in detection of the viroid and also provided a suitable extraction and hybridization method for the detection of CCCVd from oil palm.

Matched MeSH terms: Cocos/virology*; Plant Diseases/virology*
Multiple facial seborrheic keratosis-like lesions in a young woman with epidermodysplasia verruciformis

Foong HB, Ibrahimi OA, Elpern DJ, Tyring S, Rady P, Carlson JA

Int J Dermatol, 2008 May;47(5):476-8.
PMID: 18412865 DOI: 10.1111/j.1365-4632.2008.03559.x
Matched MeSH terms: Epidermodysplasia Verruciformis/virology; Skin/virology
Fulltext Lessons from the Nipah virus outbreak in Malaysia

Looi LM, Chua KB

Malays J Pathol, 2007 Dec;29(2):63-7.
PMID: 19108397 MyJurnal

The Nipah virus outbreak in Malaysia (September 1998 to May 1999) resulted in 265 cases of acute encephalitis with 105 deaths, and near collapse of the billion-dollar pig-farming industry. Because it was initially attributed to Japanese encephalitis, early control measures were ineffective, and the outbreak spread to other parts of Malaysia and nearby Singapore. The isolation of the novel aetiological agent, the Nipah virus (NiV), from the cerebrospinal fluid of an outbreak victim was the turning point which led to outbreak control 2 months later. Together with the Hendra virus, NiV is now recognised as a new genus, Henipavirus (Hendra + Nipah), in the Paramyxoviridae family. Efforts of the local and international scientific community have since elucidated the epidemiology, clinico-pathophysiology and pathogenesis of this new disease. Humans contracted the infection from close contact with infected pigs, and formed the basis for pig-culling that eventually stopped the outbreak. NiV targeted medium-sized and small blood vessels resulting in endothelial multinucleated syncytia and fibrinoid necrosis. Autopsies revealed disseminated cerebral microinfarctions resulting from vasculitis-induced thrombosis and direct neuronal involvement. The discovery of NiV in the urine and saliva of Malaysian Island flying foxes (Pteropus hypomelanus and Petropus vampyrus) implicated these as natural reservoir hosts of NiV. It is probable that initial transmission of NiV from bats to pigs occurred in late 1997/early 1998 through contamination of pig swill by bat excretions, as a result of migration of these forest fruitbats to cultivated orchards and pig-farms, driven by fruiting failure of forest trees during the El Nino-related drought and anthropogenic fires in Indonesia in 1997-1998. This outbreak emphasizes the need for sharing information of any unusual illnesses in animals and humans, an open-minded approach and close collaboration and co-ordination between the medical profession, veterinarians and wildlife specialists in the investigation of such illnesses. Environmental mismanagement (such as deforestation and haze) has far-reaching effects, including encroachment of wildlife into human habitats and the introduction of zoonotic infections into domestic animals and humans.

Matched MeSH terms: Chiroptera/virology; Swine/virology
Henipaviruses: a new family of emerging Paramyxoviruses

Wild TF

Pathol. Biol., 2009 Mar;57(2):188-96.
PMID: 18511217 DOI: 10.1016/j.patbio.2008.04.006

Paramyxoviruses have been implicated in both animal and human infections. Some viruses, such as Morbilliviruses are responsible for large-scale epidemics. However, there are limited observations of these viruses crossing the host species barrier in nature. In 1994, in Australia a fatal infection in horses and humans was identified to be caused by a new Paramyxovirus, Hendra virus (HeV), and in 1998 in Malaysia, a closely related virus, Nipah virus (NiV) was responsible for fatal infections in pigs and humans. These two viruses were sufficiently different from previously described Paramyxoviruses to create a new genus, Henipaviruses. The natural reservoir of these viruses was the fruit bat (Pteropus), which is found in regions extending from the western Pacific to the eastern coast of Africa. Serological studies have established that as many as half the fruit bats in colonies throughout these regions may have antibodies against this family of viruses. The availability of diagnostic reagents for Nipah virus in humans have identified infections in several countries including, Bangladesh, India and Indonesia. In some of these epidemics, mortality in humans exceeds 75%. Deforestation is probably responsible for fruit bats leaving their ecological niches and approaching farms and villages. The infection of humans and animals may occur via contaminated foods or in certain cases by animals to man. At present, only within close families has human-to-human transmission been proposed. Henipavirus infections are probably more widespread than it is at presently known and so it is important to have an intense monitoring for these diseases, especially in countries where large-scale deforestation is happening.

Matched MeSH terms: Chiroptera/virology; Horse Diseases/virology
Fulltext Absence of Melaka-virus in European children with respiratory disease

Schildgen V, Rüngeler E, Tillmann R, Schildgen O

J Clin Virol, 2008 Jul;42(3):295-6.
PMID: 18359270 DOI: 10.1016/j.jcv.2008.02.003
Matched MeSH terms: Reoviridae Infections/virology*; Respiratory Tract Infections/virology*
The emergence of Nipah virus, a highly pathogenic paramyxovirus

Lo MK, Rota PA

J Clin Virol, 2008 Dec;43(4):396-400.
PMID: 18835214 DOI: 10.1016/j.jcv.2008.08.007

Nipah virus first emerged in Malaysia and Singapore between 1998 and 1999, causing severe febrile encephalitis in humans with a mortality rate of close to 40%. In addition, a significant portion of those recovering from acute infection had relapse encephalitis and long-term neurological defects. Since its initial outbreak, there have been numerous outbreaks in Bangladesh and India, in which the mortality rate rose to approximately 70%. These subsequent outbreaks were distinct from the initial outbreak, both in their epidemiology and in their clinical presentations. Recent developments in diagnostics may expedite disease diagnosis and outbreak containment, while progress in understanding the molecular biology of Nipah virus could lead to novel therapeutics and vaccines for this deadly pathogen.

Matched MeSH terms: Encephalitis, Viral/virology; Henipavirus Infections/virology
[Nipah encephalitis]

Kolomytsev AA, Kurinnov VV, Mikolaĭchuk SV, Zakutskiĭ NI

Vopr. Virusol., 2008 Mar-Apr;53(2):10-3.
PMID: 18450103

Nipah encephalitis is a particular dangerous disease that affects animals and man. Fatal cases of the disease have been identified in the persons looking after pigs in the villages of Malaysia. The causative agent is presumably referred to as morbilliviruses of the Paramixoviridae family. Two hundred persons died among the ill patients with the signs of encephalitis. The principal hosts of the virus were fox-bats (Megaschiroptera) inhabiting in the surrounding forests. The present paper descries the epidemiological features of the disease, its clinical manifestations, abnormal anatomic changes, diagnosis, and implemented controlling measures.

Matched MeSH terms: Chiroptera/virology; Disease Reservoirs/virology
Henipaviruses: emerging paramyxoviruses associated with fruit bats

Field HE, Mackenzie JS, Daszak P

Curr. Top. Microbiol. Immunol., 2007;315:133-59.
PMID: 17848064

Two related, novel, zoonotic paramyxoviruses have been described recently. Hendra virus was first reported in horses and thence humans in Australia in 1994; Nipah virus was first reported in pigs and thence humans in Malaysia in 1998. Human cases of Nipah virus infection, apparently unassociated with infection in livestock, have been reported in Bangladesh since 2001. Species of fruit bats (genus Pteropus) have been identified as natural hosts of both agents. Anthropogenic changes (habitat loss, hunting) that have impacted the population dynamics of Pteropus species across much of their range are hypothesised to have facilitated emergence. Current strategies for the management of henipaviruses are directed at minimising contact with the natural hosts, monitoring identified intermediate hosts, improving biosecurity on farms, and better disease recognition and diagnosis. Investigation of the emergence and ecology of henipaviruses warrants a broad, cross-disciplinary ecosystem health approach that recognises the critical linkages between human activity, ecological change, and livestock and human health.

Matched MeSH terms: Chiroptera/virology*; Disease Reservoirs/virology
Fulltext Re-emergence of Chikungunya virus in Malaysia

Kumarasamy V, Prathapa S, Zuridah H, Chem YK, Norizah I, Chua KB

Med J Malaysia, 2006 Jun;61(2):221-5.
PMID: 16898316 MyJurnal

An outbreak of Chikugunya (CHIK) fever occurred among the fishing community in Bagan Pancor, Perak. The outbreak was laboratory confirmed within 48 hours after the receipt of the specimens. Fifty-three patients' serum samples were submitted for laboratory investigation and 47 (88.7%) were confirmed to be positive for CHIK infection by RT-PCR, and/or virus isolation, and/or in-house immunoflourescent test. RT-PCR and virus isolation were the tests of choice for patients with illness of four days or less and detection of CHIK specific IgM for those with more than four days of fever. The nucleic acid sequence based on the 354- and 294-bp of the nsP1 and E1 genes of the CHIK virus detected from pools of adults Aedes aegypti mosquitoes were identical to those CHIKV virus isolated from humans in the same locality. Phylogenetic analysis of the CHIK virus based on the 257 nts partial E1 gene indicates that Bagan Panchor's strain was closely related to the first CHIK virus isolated during the outbreak in Klang in 1998.

Matched MeSH terms: Aedes/virology; Alphavirus Infections/virology
Outlook of dengue in Malaysia: a century later

Abubakar S, Shafee N

Malays J Pathol, 2002 Jun;24(1):23-7.
PMID: 16329552

Dengue continues to be a major health threat to Malaysia a century after its first reported outbreak in 1902. Examination of the available outbreak data suggested that a major DF/DHF outbreak occurred in Malaysia in a cyclical pattern of approximately every 8 years. All four dengue virus serotypes are found co-circulating in Malaysia, but after the first and only major outbreak involving DEN-4 in 1960's, only DEN-1, DEN-2 and DEN-3 were associated with DF/DHF outbreaks. It is argued that perhaps the spread of the later dengue virus serotypes followed the pattern of spread of the mosquito vector Aedes aegypti, whereas the former was associated with Aedes albopictus, the outdoor and rural area dwelling mosquito. Estimating from the trend and pattern of dengue and the associated dengue virus serotypes, unless there is a major breakthrough in dengue vaccine development, it is likely that dengue outbreaks will continue to occur in Malaysia throughout the 21st century.

Matched MeSH terms: Aedes/virology; Dengue/virology*
Fulltext The clinical features and outcomes of acute liver failure associated with dengue infection in adults: a case series

Tan SS, Bujang MA

Braz J Infect Dis, 2013 Mar-Apr;17(2):164-9.
PMID: 23453417 DOI: 10.1016/j.bjid.2012.09.007

OBJECTIVE: To describe the clinical manifestations and outcome of acute liver failure (ALF) associated with dengue viral infection, a rare but severe complication.
METHODS: One hundred and fifty five consecutive patients with ALF admitted to the national liver centre from 2001 to 2009 were reviewed retrospectively. Eight cases due to dengue infection were identified and their clinical characteristics are described.
RESULTS: All patients had severe dengue with one dengue shock syndrome. The median (minimum, maximum) age was 33.5 (17, 47) years with 50% female. The median (minimum, maximum) duration from the onset of fever to development of ALF was 7.5 (5, 13) days and the maximum hepatic encephalopathy (HE) grade were III in five patients and II in three patients. Three patients had systemic inflammatory responses (SIRS) on admission and were in grade III HE. The presence of SIRS on admission was associated with higher grade of HE and its development during the course of hospitalization was associated with worsening HE grade. The hepatitis was characterized by marked elevations in: alanine transaminase [median admission 1140.5 u/L (639, 4161); median peak 2487 u/L (998, 5181)], serum bilirubin [median admission 29 μmol/L (23, 291); median peak 127 μmol/L (72, 592)], and prothrombin time [median admission 16.8s (15.3, 26.2); median peak 22s (15.3, 40.7)]. The survival rate with standard medical therapy alone was 100%.
CONCLUSIONS: Dengue associated ALF manifest about one week after the onset of fever with severe hepatitis and encephalopathy. In our experience, the outcome with standard medical therapy alone is excellent.

Matched MeSH terms: Hepatitis, Viral, Human/virology*; Liver Failure, Acute/virology*
Detection and Quantification of Chikungunya Virus by Real-Time RT-PCR Assay

Wang SM, Ali UH, Sekaran SD, Thayan R

Methods Mol Biol, 2016;1426:105-17.
PMID: 27233265 DOI: 10.1007/978-1-4939-3618-2_10

Real-time PCR assay has many advantages over conventional PCR methods, including rapidity, quantitative measurement, low risk of contamination, high sensitivity, high specificity, and ease of standardization (Mackay et al., Nucleic Acids Res 30:1292-1305, 2002). The real-time PCR system relies upon the measurement of a fluorescent reporter during PCR, in which the amount of emitted fluorescence is directly proportional to the amount of the PCR product in a reaction (Gibsons et al., Genome Res 6:995-1001, 1996). Here, we describe the use of SYBR Green I-based and TaqMan(®) real-time reverse transcription polymerase chain reaction (RT-PCR) for the detection and quantification of Chikungunya virus (CHIKV).

Matched MeSH terms: Haplorhini/virology; Culicidae/virology
Fulltext Projections of the current and future disease burden of hepatitis C virus infection in Malaysia

McDonald SA, Dahlui M, Mohamed R, Naning H, Shabaruddin FH, Kamarulzaman A

PLoS One, 2015;10(6):e0128091.
PMID: 26042425 DOI: 10.1371/journal.pone.0128091

BACKGROUND: The prevalence of hepatitis C virus (HCV) infection in Malaysia has been estimated at 2.5% of the adult population. Our objective, satisfying one of the directives of the WHO Framework for Global Action on Viral Hepatitis, was to forecast the HCV disease burden in Malaysia using modelling methods.
METHODS: An age-structured multi-state Markov model was developed to simulate the natural history of HCV infection. We tested three historical incidence scenarios that would give rise to the estimated prevalence in 2009, and calculated the incidence of cirrhosis, end-stage liver disease, and death, and disability-adjusted life-years (DALYs) under each scenario, to the year 2039. In the baseline scenario, current antiviral treatment levels were extended from 2014 to the end of the simulation period. To estimate the disease burden averted under current sustained virological response rates and treatment levels, the baseline scenario was compared to a counterfactual scenario in which no past or future treatment is assumed.
RESULTS: In the baseline scenario, the projected disease burden for the year 2039 is 94,900 DALYs/year (95% credible interval (CrI): 77,100 to 124,500), with 2,002 (95% CrI: 1340 to 3040) and 540 (95% CrI: 251 to 1,030) individuals predicted to develop decompensated cirrhosis and hepatocellular carcinoma, respectively, in that year. Although current treatment practice is estimated to avert a cumulative total of 2,200 deaths from DC or HCC, a cumulative total of 63,900 HCV-related deaths is projected by 2039.
CONCLUSIONS: The HCV-related disease burden is already high and is forecast to rise steeply over the coming decades under current levels of antiviral treatment. Increased governmental resources to improve HCV screening and treatment rates and to reduce transmission are essential to address the high projected HCV disease burden in Malaysia.

Matched MeSH terms: Hepatitis C/virology; Carcinoma, Hepatocellular/virology

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