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  1. Identification of Optimal Reference Genes for Normalization of RT-qPCR Data in Cancerous and Non-Cancerous Tissues of Human Uterine Cervix
    Tan SC, Ismail MP, Duski DR, Othman NH, Bhavaraju VM, Ankathil R
    Cancer Invest, 2017 Mar 16;35(3):163-173.
    PMID: 28301252 DOI: 10.1080/07357907.2017.1278767
    This study aimed to identify the most stably expressed reference genes from a panel of 32 candidate genes for normalization of reverse transcription-quantitative real-time polymerase chain reaction data in cancerous and non-cancerous tissues of human uterine cervix. Overall, PUM1, YWHAZ, and RPLP0 were identified as the most stably expressed genes in paired cancerous and non-cancerous tissues. The results were further stratified by the state of malignancy of the tissues, histopathological type of the cancer, and the human papillomavirus-type.
    Matched MeSH terms: Carcinoma, Squamous Cell/virology; Uterine Cervical Neoplasms/virology; Papillomavirus Infections/virology
  2. Fulltext Nipah virus dynamics in bats and implications for spillover to humans
    Epstein JH, Anthony SJ, Islam A, Kilpatrick AM, Ali Khan S, Balkey MD, et al.
    Proc Natl Acad Sci U S A, 2020 11 17;117(46):29190-29201.
    PMID: 33139552 DOI: 10.1073/pnas.2000429117
    Nipah virus (NiV) is an emerging bat-borne zoonotic virus that causes near-annual outbreaks of fatal encephalitis in South Asia-one of the most populous regions on Earth. In Bangladesh, infection occurs when people drink date-palm sap contaminated with bat excreta. Outbreaks are sporadic, and the influence of viral dynamics in bats on their temporal and spatial distribution is poorly understood. We analyzed data on host ecology, molecular epidemiology, serological dynamics, and viral genetics to characterize spatiotemporal patterns of NiV dynamics in its wildlife reservoir, Pteropus medius bats, in Bangladesh. We found that NiV transmission occurred throughout the country and throughout the year. Model results indicated that local transmission dynamics were modulated by density-dependent transmission, acquired immunity that is lost over time, and recrudescence. Increased transmission followed multiyear periods of declining seroprevalence due to bat-population turnover and individual loss of humoral immunity. Individual bats had smaller host ranges than other Pteropus species (spp.), although movement data and the discovery of a Malaysia-clade NiV strain in eastern Bangladesh suggest connectivity with bats east of Bangladesh. These data suggest that discrete multiannual local epizootics in bat populations contribute to the sporadic nature of NiV outbreaks in South Asia. At the same time, the broad spatial and temporal extent of NiV transmission, including the recent outbreak in Kerala, India, highlights the continued risk of spillover to humans wherever they may interact with pteropid bats and the importance of limiting opportunities for spillover throughout Pteropus's range.
    Matched MeSH terms: Chiroptera/virology*; Zoonoses/virology; Henipavirus Infections/virology*
  3. Fulltext Alzheimer's disease-like perturbations in HIV-mediated neuronal dysfunctions: understanding mechanisms and developing therapeutic strategies
    Jha NK, Sharma A, Jha SK, Ojha S, Chellappan DK, Gupta G, et al.
    Open Biol, 2020 Dec;10(12):200286.
    PMID: 33352062 DOI: 10.1098/rsob.200286
    Excessive exposure to toxic substances or chemicals in the environment and various pathogens, including viruses and bacteria, is associated with the onset of numerous brain abnormalities. Among them, pathogens, specifically viruses, elicit persistent inflammation that plays a major role in Alzheimer's disease (AD) as well as dementia. AD is the most common brain disorder that affects thought, speech, memory and ability to execute daily routines. It is also manifested by progressive synaptic impairment and neurodegeneration, which eventually leads to dementia following the accumulation of Aβ and hyperphosphorylated Tau. Numerous factors contribute to the pathogenesis of AD, including neuroinflammation associated with pathogens, and specifically viruses. The human immunodeficiency virus (HIV) is often linked with HIV-associated neurocognitive disorders (HAND) following permeation through the blood-brain barrier (BBB) and induction of persistent neuroinflammation. Further, HIV infections also exhibited the ability to modulate numerous AD-associated factors such as BBB regulators, members of stress-related pathways as well as the amyloid and Tau pathways that lead to the formation of amyloid plaques or neurofibrillary tangles accumulation. Studies regarding the role of HIV in HAND and AD are still in infancy, and potential link or mechanism between both is not yet established. Thus, in the present article, we attempt to discuss various molecular mechanisms that contribute to the basic understanding of the role of HIV-associated neuroinflammation in AD and HAND. Further, using numerous growth factors and drugs, we also present possible therapeutic strategies to curb the neuroinflammatory changes and its associated sequels.
    Matched MeSH terms: Brain/virology; Neurons/virology; HIV Infections/virology
  4. Fulltext Targeted disruption of pi-pi stacking in Malaysian banana lectin reduces mitogenicity while preserving antiviral activity
    Covés-Datson EM, King SR, Legendre M, Swanson MD, Gupta A, Claes S, et al.
    Sci Rep, 2021 01 12;11(1):656.
    PMID: 33436903 DOI: 10.1038/s41598-020-80577-7
    Lectins, carbohydrate-binding proteins, have been regarded as potential antiviral agents, as some can bind glycans on viral surface glycoproteins and inactivate their functions. However, clinical development of lectins has been stalled by the mitogenicity of many of these proteins, which is the ability to stimulate deleterious proliferation, especially of immune cells. We previously demonstrated that the mitogenic and antiviral activities of a lectin (banana lectin, BanLec) can be separated via a single amino acid mutation, histidine to threonine at position 84 (H84T), within the third Greek key. The resulting lectin, H84T BanLec, is virtually non-mitogenic but retains antiviral activity. Decreased mitogenicity was associated with disruption of pi-pi stacking between two aromatic amino acids. To examine whether we could provide further proof-of-principle of the ability to separate these two distinct lectin functions, we identified another lectin, Malaysian banana lectin (Malay BanLec), with similar structural features as BanLec, including pi-pi stacking, but with only 63% amino acid identity, and showed that it is both mitogenic and potently antiviral. We then engineered an F84T mutation expected to disrupt pi-pi stacking, analogous to H84T. As predicted, F84T Malay BanLec (F84T) was less mitogenic than wild type. However, F84T maintained strong antiviral activity and inhibited replication of HIV, Ebola, and other viruses. The F84T mutation disrupted pi-pi stacking without disrupting the overall lectin structure. These findings show that pi-pi stacking in the third Greek key is a conserved mitogenic motif in these two jacalin-related lectins BanLec and Malay BanLec, and further highlight the potential to rationally engineer antiviral lectins for therapeutic purposes.
    Matched MeSH terms: Leukocytes, Mononuclear/virology; HIV Infections/virology; Hemorrhagic Fever, Ebola/virology
  5. Fulltext Molecular epidemiology and evolutionary histories of human coronavirus OC43 and HKU1 among patients with upper respiratory tract infections in Kuala Lumpur, Malaysia
    Al-Khannaq MN, Ng KT, Oong XY, Pang YK, Takebe Y, Chook JB, et al.
    Virol J, 2016 Feb 25;13:33.
    PMID: 26916286 DOI: 10.1186/s12985-016-0488-4
    BACKGROUND: Despite the worldwide circulation of human coronavirus OC43 (HCoV-OC43) and HKU1 (HCoV-HKU1), data on their molecular epidemiology and evolutionary dynamics in the tropical Southeast Asia region is lacking.
    METHODS: The study aimed to investigate the genetic diversity, temporal distribution, population history and clinical symptoms of betacoronavirus infections in Kuala Lumpur, Malaysia between 2012 and 2013. A total of 2,060 adults presented with acute respiratory symptoms were screened for the presence of betacoronaviruses using multiplex PCR. The spike glycoprotein, nucleocapsid and 1a genes were sequenced for phylogenetic reconstruction and Bayesian coalescent inference.
    RESULTS: A total of 48/2060 (2.4 %) specimens were tested positive for HCoV-OC43 (1.3 %) and HCoV-HKU1 (1.1 %). Both HCoV-OC43 and HCoV-HKU1 were co-circulating throughout the year, with the lowest detection rates reported in the October-January period. Phylogenetic analysis of the spike gene showed that the majority of HCoV-OC43 isolates were grouped into two previously undefined genotypes, provisionally assigned as novel lineage 1 and novel lineage 2. Sign of natural recombination was observed in these potentially novel lineages. Location mapping showed that the novel lineage 1 is currently circulating in Malaysia, Thailand, Japan and China, while novel lineage 2 can be found in Malaysia and China. Molecular dating showed the origin of HCoV-OC43 around late 1950s, before it diverged into genotypes A (1960s), B (1990s), and other genotypes (2000s). Phylogenetic analysis revealed that 27.3 % of the HCoV-HKU1 strains belong to genotype A while 72.7 % belongs to genotype B. The tree root of HCoV-HKU1 was similar to that of HCoV-OC43, with the tMRCA of genotypes A and B estimated around the 1990s and 2000s, respectively. Correlation of HCoV-OC43 and HCoV-HKU1 with the severity of respiratory symptoms was not observed.
    CONCLUSIONS: The present study reported the molecular complexity and evolutionary dynamics of human betacoronaviruses among adults with acute respiratory symptoms in a tropical country. Two novel HCoV-OC43 genetic lineages were identified, warranting further investigation on their genotypic and phenotypic characteristics.
    Study site: Primary Care Clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
    Matched MeSH terms: Nasopharynx/virology; Respiratory Tract Infections/virology*; Coronavirus Infections/virology*
  6. Fulltext The SARS, MERS and novel coronavirus (COVID-19) epidemics, the newest and biggest global health threats: what lessons have we learned?
    Peeri NC, Shrestha N, Rahman MS, Zaki R, Tan Z, Bibi S, et al.
    Int J Epidemiol, 2020 Jun 01;49(3):717-726.
    PMID: 32086938 DOI: 10.1093/ije/dyaa033
    OBJECTIVES: To provide an overview of the three major deadly coronaviruses and identify areas for improvement of future preparedness plans, as well as provide a critical assessment of the risk factors and actionable items for stopping their spread, utilizing lessons learned from the first two deadly coronavirus outbreaks, as well as initial reports from the current novel coronavirus (COVID-19) epidemic in Wuhan, China.

    METHODS: Utilizing the Centers for Disease Control and Prevention (CDC, USA) website, and a comprehensive review of PubMed literature, we obtained information regarding clinical signs and symptoms, treatment and diagnosis, transmission methods, protection methods and risk factors for Middle East respiratory syndrome (MERS), severe acute respiratory syndrome (SARS) and COVID-19. Comparisons between the viruses were made.

    RESULTS: Inadequate risk assessment regarding the urgency of the situation, and limited reporting on the virus within China has, in part, led to the rapid spread of COVID-19 throughout mainland China and into proximal and distant countries. Compared with SARS and MERS, COVID-19 has spread more rapidly, due in part to increased globalization and the focus of the epidemic. Wuhan, China is a large hub connecting the North, South, East and West of China via railways and a major international airport. The availability of connecting flights, the timing of the outbreak during the Chinese (Lunar) New Year, and the massive rail transit hub located in Wuhan has enabled the virus to perforate throughout China, and eventually, globally.

    CONCLUSIONS: We conclude that we did not learn from the two prior epidemics of coronavirus and were ill-prepared to deal with the challenges the COVID-19 epidemic has posed. Future research should attempt to address the uses and implications of internet of things (IoT) technologies for mapping the spread of infection.

    Matched MeSH terms: Pneumonia, Viral/virology; Coronavirus Infections/virology; Severe Acute Respiratory Syndrome/virology
  7. Effects of ribavirin and hydroxyurea on oral infection of Aedes aegypti (L.) with dengue virus
    Lee HL, Phong TV, Rohani A
    Southeast Asian J Trop Med Public Health, 2012 Nov;43(6):1358-64.
    PMID: 23413698
    This study was conducted to determine the inhibitory effects of ribavirin and hydroxyurea on dengue virus replication in Aedes aegypti mosquitoes. Female Ae. aegypti mosquitoes were infected with dengue-2 virus and fed ribavirin at a dose of 0.3 mg/ml and/or hydroxyurea at a dose of 6 mg/ml via artificial membrane feeding technique. The virus in infected mosquitoes was isolated using C6/36 cell culture. Peroxidase-antiperoxidase (PAP) staining was used to detect dengue-infected C6/36 cells and to quantify the level of infection by determining the presence of infected cells. In mosquitoes treated with ribavirin alone, hydroxyurea alone or both drugs in combination had reductions in dengue infection rates of 87.72, 89.47 and 95.61%, respectively. The mortalities of female Ae. aegypti mosquitoes fed with these drugs were significantly higher than the control. Ribavirin also had an inhibitory effect on the fecundity of female Ae. aegypti mosquitoes.
    Matched MeSH terms: Aedes/virology; Dengue/virology; Insect Vectors/virology
  8. The influence of antibody levels in dengue diagnosis by polymerase chain reaction
    Chan SY, Kautner IM, Lam SK
    J Virol Methods, 1994 Oct;49(3):315-22.
    PMID: 7868649
    The potential of RT-PCR to rapidly diagnose dengue infections from both acute and convalescent phase patients' sera was evaluated. The RNA extraction method involved binding of the viral RNA to silica particles in the presence of high concentration of guanidine thiocyanate. The protocol that was established was sensitive enough to detect 40 plaque forming units per 100 microliter of serum and results could be obtained within one day. Results from this study indicate that clinical samples should be collected in the early acute phase of illness when anti-dengue antibodies were undetectable or of low titres to ensure a more reliable diagnosis.
    Matched MeSH terms: Dengue/virology; Virology/methods*
  9. Fulltext Saffold virus infection in children, Malaysia, 2009
    Chua KB, Voon K, Yu M, Ali WN, Kasri AR, Wang LF
    Emerg Infect Dis, 2011 Aug;17(8):1562-4.
    PMID: 21801653 DOI: 10.3201/eid1708.101380
    Matched MeSH terms: Pharyngitis/virology; Pharynx/virology; Cardiovirus Infections/virology
  10. Prevalence of feline coronavirus in two cat populations in Malaysia
    Sharif S, Arshad SS, Hair-Bejo M, Omar AR, Zeenathul NA, Hafidz MA
    J Feline Med Surg, 2009 Dec;11(12):1031-4.
    PMID: 19818660 DOI: 10.1016/j.jfms.2009.08.005
    The prevalence of feline coronavirus (FCoV) was studied in two catteries in Malaysia. Rectal swabs or faecal samples were collected from a total of 44 clinically healthy Persian purebred and mix-breed cats. RNA extracted from the faecal material was subjected to a reverse transcription-polymerase chain reaction (RT-PCR) using primers flanking for a conserved region of the virus genome. The overall prevalence of FCoV infection was 84% and the infection rate was higher in Persian purebred cats (96%) than mix-breed cats (70%). There was no significant association between the age or gender of tested cats and shedding the virus. This study is the first PCR-based survey for FCoV in Malaysia and showed the ubiquitous presence of FCoV in Malaysian cat colonies.
    Matched MeSH terms: Cat Diseases/virology; Feces/virology; Coronavirus Infections/virology
  11. Fulltext Development of conventional and real-time reverse transcription polymerase chain reaction assays to detect Tembusu virus in Culex tarsalis mosquitoes
    Petz LN, Turell MJ, Padilla S, Long LS, Reinbold-Wasson DD, Smith DR, et al.
    Am J Trop Med Hyg, 2014 Oct;91(4):666-71.
    PMID: 25114013 DOI: 10.4269/ajtmh.13-0218
    Tembusu virus (TMUV) is an important emerging arthropod-borne virus that may cause encephalitis in humans and has been isolated in regions of southeast Asia, including Malaysia, Thailand, and China. Currently, detection and identification of TMUV are limited to research laboratories, because quantitative rapid diagnostic assays for the virus do not exist. We describe the development of sensitive and specific conventional and real-time quantitative reverse transcription polymerase chain reaction assays for detecting TMUV RNA in infected cell culture supernatant and Culex tarsalis mosquitoes. We used this assay to document the replication of TMUV in Cx. tarsalis, where titers increased 1,000-fold 5 days after inoculation. These assays resulted in the detection of virus-specific RNA in the presence of copurified mosquito nucleic acids. The use of these rapid diagnostic assays may have future applications for field pathogen surveillance and may assist in early detection, diagnosis, and control of the associated arthropod-borne pathogens.
    Matched MeSH terms: Culex/virology*; Insect Vectors/virology*; Flavivirus Infections/virology
  12. HBV and HIV co-infection: Prevalence and clinical outcomes in tertiary care hospital Malaysia
    Akhtar A, Khan AH, Sulaiman SA, Soo CT, Khan K
    J Med Virol, 2016 Mar;88(3):455-60.
    PMID: 26255632 DOI: 10.1002/jmv.24347
    According to WHO, Malaysia has been classified as a concentrated epidemic country due to progression of HIV infection in the population of injecting drug users. The main objectives of current study are to determine the prevalence of HBV among HIV-positive individuals in a tertiary care hospital of Malaysia and to assess the predictors involved in the outcomes of HIV-HBV co-infected patients. A retrospective, cross-sectional study is conducted at Hospital Palau Pinang, Malaysia. The collection of socio-demographic data as well as clinical data is done with the help of data collection form. Data were analyzed after putting the collected values of required data by using statistical software SPSS version 20.0 and P > 0.05 is considered as significant. Results show that the overall prevalence of HBV was 86 (13%) including 495 (74.5%) males and 169 (25.5%) females among a total of 664 HIV-infected patients. It was observed that there is a high prevalence of HIV-HBV co-infection in males 76 (11.4%) as compared to females 10 (1.5%) (P = 0.002). The median age of the study population was 39 years. The statistical significant risk factors involved in the outcomes of HIV-HBV co-infected patients were observed in the variables of gender, age groups, and injecting drug users. The findings of the present study shows that the prevalence of HBV infection among HIV-positive patients was 13% and the risk factors involved in the outcomes of HIV-HBV co-infected patients were gender, age, and intravenous drug users.
    Matched MeSH terms: Hepatitis B/virology; Hepatitis C/virology; HIV Infections/virology
  13. Fulltext Detection of novel respiratory viruses from influenza-like illness in the Philippines
    Furuse Y, Suzuki A, Kishi M, Galang HO, Lupisan SP, Olveda RM, et al.
    J Med Virol, 2010 May;82(6):1071-4.
    PMID: 20419824 DOI: 10.1002/jmv.21763
    Several novel viruses have been recently identified in respiratory samples. However, the epidemiology of these viruses in tropical countries remains unclear. The aim of the present study was to provide an overview of the epidemiology of novel respiratory viruses, including human metapneumovirus, human bocavirus, new subtypes of human coronavirus (NL63 and HKU1), KI virus, WU virus, and Melaka virus in the Philippines, a tropical country. Nasopharyngeal aspirates from 465 patients with influenza-like illness were collected in 2006 and 2007. Reverse transcription polymerase chain reaction (RT-PCR) and PCR were performed to detect viruses from culture-negative specimens. Human metapneumovirus, human bocavirus, human coronavirus HKU1, KI virus, and WU virus were detected for the first time in the Philippines; Melaka virus was not found.
    Matched MeSH terms: Nasopharynx/virology*; Respiratory Tract Infections/virology*; Virus Diseases/virology*
  14. Identification of a human group C rotavirus in Malaysia
    Rasool NB, Hamzah M, Jegathesan M, Wong YH, Qian Y, Green KY
    J Med Virol, 1994 Jul;43(3):209-11.
    PMID: 7931180
    Stool specimens from 334 infants and young children hospitalized with diarrhea in the General Hospital, Kuala Lumpur, Malaysia between August and November, 1987 were analyzed for the presence of rotavirus double-stranded (ds) RNA by polyacrylamide gel electrophoresis. Of the 334 specimens analyzed, 32 (9.6%) were positive for rotavirus RNA. One specimen (designated G147) exhibited a ds RNA electropherotype profile characteristic of Group C rotavirus and was selected for further characterization. In Northern blot hybridization studies, the gene 5 segment of strain G147 hybridized with a cDNA probe generated from the cloned gene 5 (which encodes the VP6 inner capsid protein that is group specific) of porcine Group C rotavirus strain Cowden, confirming the classification of strain G147 in Group C. The association of Group C rotavirus with diarrheal illness in Malaysia is consistent with earlier studies that suggest a global distribution of this virus and supports the need for additional epidemiologic studies.
    Matched MeSH terms: Diarrhea/virology; Gastroenteritis/virology*; Rotavirus Infections/virology*
  15. Outbreak of acute hemorrhagic conjunctivitis in French Guiana and West Indies caused by coxsackievirus A24 variant: phylogenetic analysis reveals Asian import
    Dussart P, Cartet G, Huguet P, Lévêque N, Hajjar C, Morvan J, et al.
    J Med Virol, 2005 Apr;75(4):559-65.
    PMID: 15714481
    An outbreak of acute hemorrhagic conjunctivitis occurred in French Guiana between April and July 2003, with approximately 6,000 cases in the two major cities Kourou and Cayenne. Since acute hemorrhagic conjunctivitis is not a notifiable disease in France, there was no registration of the number of cases. Therefore, these were estimated by comparing the consumption of antibiotic eye drops and ophthalmic ointments during 2002 and 2003. The outbreak rapidly spread into the Caribbean Islands, causing an outbreak in Guadeloupe in October. Viral isolates from conjunctival swabs of 16 patients were confirmed to be enterovirus by PCR directed to the 5' UTR of the genome. The isolates could not be neutralized by the Melnick intersecting pools, but were shown to be CV-A24 variant by limited sequencing within the VP1 and 3C regions of 12 strains. Phylogenetic analysis revealed that they were similar to the genotype III strains causing outbreaks in Korea 2002 and Malaysia 2003. The previous outbreak of conjunctivitis caused by CV-A24 in the Caribbean in the 1980s was also introduced from Asia, and disappeared after 3 years. This new introduction from Asia and its rapid spread into the Caribbean, where the infection disappeared after a few months, indicates that the CV-A24 variant has a different epidemiological pattern in this region compared to South East Asia, since it has not established an endemic infection. It had to be reintroduced from Asia, where it has been circulating since the 1970s.
    Matched MeSH terms: Conjunctivitis, Acute Hemorrhagic/virology; Coxsackievirus Infections/virology; Communicable Diseases, Emerging/virology
  16. Fulltext Development of Novel Vaccines against Enterovirus-71
    Yee PT, Poh CL
    Viruses, 2015 Dec 30;8(1).
    PMID: 26729152 DOI: 10.3390/v8010001
    The hand, foot and mouth disease is caused by a group of Enteroviruses such as Enterovirus 71 (EV-A71) and Coxsackievirus CV-A5, CV-A8, and CV-A16. Mild symptoms of EV-A71 infection in children range from high fever, vomiting, rashes and ulcers in mouth but can produce more severe symptoms such as brainstem and cerebellar encephalitis, leading up to cardiopulmonary failure and death. The lack of vaccines and antiviral drugs against EV-A71 highlights the urgency of developing preventive and treatment agents against EV-A71 to prevent further fatalities. Research groups have developed experimental inactivated vaccines, recombinant Viral Protein 1 (VP1) vaccine and virus-like particles (VLPs). The inactivated EV-A71 vaccine is considered the safest viral vaccine, as there will be no reversion to the infectious wild type strain. The recombinant VP1 vaccine is a cost-effective immunogen, while VLPs contain an arrangement of epitopes that can elicit neutralizing antibodies against the virus. As each type of vaccine has its advantages and disadvantages, increased studies are required in the development of such vaccines, whereby high efficacy, long-lasting immunity, minimal risk to those vaccinated, safe and easy production, low cost, dispensing the need for refrigeration and convenient delivery are the major goals in their design.
    Matched MeSH terms: Coxsackievirus Infections/virology
  17. Retinopathy in a patient with acute Epstein-Barr virus infection: follow-up analysis using spectral domain optical coherence tomography
    Weller JM, Bergua A, Mardin CY
    Retin Cases Brief Rep, 2015;9(1):72-7.
    PMID: 25383851 DOI: 10.1097/ICB.0000000000000087
    To describe the clinical findings, diagnostics, and differential diagnosis in a patient with retinopathy in acute systemic Epstein-Barr virus (EBV) infection.
    Matched MeSH terms: Retinal Diseases/virology*
  18. Identification of new sub-genotypes of virulent Newcastle disease virus with potential panzootic features
    Miller PJ, Haddas R, Simanov L, Lublin A, Rehmani SF, Wajid A, et al.
    Infect Genet Evol, 2015 Jan;29:216-29.
    PMID: 25445644 DOI: 10.1016/j.meegid.2014.10.032
    Virulent Newcastle disease virus (NDV) isolates from new sub-genotypes within genotype VII are rapidly spreading through Asia and the Middle East causing outbreaks of Newcastle disease (ND) characterized by significant illness and mortality in poultry, suggesting the existence of a fifth panzootic. These viruses, which belong to the new sub-genotypes VIIh and VIIi, have epizootic characteristics and do not appear to have originated directly from other genotype VII NDV isolates that are currently circulating elsewhere, but are related to the present and past Indonesian NDV viruses isolated from wild birds since the 80s. Viruses from sub-genotype VIIh were isolated in Indonesia (2009-2010), Malaysia (2011), China (2011), and Cambodia (2011-2012) and are closely related to the Indonesian NDV isolated in 2007, APMV1/Chicken/Karangasem, Indonesia (Bali-01)/2007. Since 2011 and during 2012 highly related NDV isolates from sub-genotype VIIi have been isolated from poultry production facilities and occasionally from pet birds, throughout Indonesia, Pakistan and Israel. In Pakistan, the viruses of sub-genotype VIIi have replaced NDV isolates of genotype XIII, which were commonly isolated in 2009-2011, and they have become the predominant sub-genotype causing ND outbreaks since 2012. In a similar fashion, the numbers of viruses of sub-genotype VIIi isolated in Israel increased in 2012, and isolates from this sub-genotype are now found more frequently than viruses from the previously predominant sub-genotypes VIId and VIIb, from 2009 to 2012. All NDV isolates of sub-genotype VIIi are approximately 99% identical to each other and are more closely related to Indonesian viruses isolated from 1983 through 1990 than to those of genotype VII, still circulating in the region. Similarly, in addition to the Pakistani NDV isolates of the original genotype XIII (now called sub-genotype XIIIa), there is an additional sub-genotype (XIIIb) that was initially detected in India and Iran. This sub-genotype also appears to have as an ancestor a NDV strain from an Indian cockatoo isolated in 1982. These data suggest the existence of a new panzootic composed of viruses of subgenotype VIIi and support our previous findings of co-evolution of multiple virulent NDV genotypes in unknown reservoirs, e.g. as recorded with the virulent NDV identified in Dominican Republic in 2008. The co-evolution of at least three different sub-genotypes reported here and the apparent close relationship of some of those genotypes from ND viruses isolated from wild birds, suggests that identifying wild life reservoirs may help predict new panzootics.
    Matched MeSH terms: Newcastle Disease/virology*
  19. [A possible fifth dengue virus serotype]
    da Silva Voorham JM
    Ned Tijdschr Geneeskd, 2014;158:A7946.
    PMID: 25227888
    Sylvatic dengue viruses are both evolutionarily and ecologically distinguishable from the human dengue virus (DENV). Sporadic episodes of sylvatic human infections in West Africa and Southeast Asia suggest that sylvatic DENV regularly come into contact with human beings. Following a study on the sylvatic transmission cycle in Malaysia in 2007, researchers announced that a new DENV serotype, DENV-5, had been discovered. Scientists are still sceptical about these new findings, and indicate that more data is necessary to determine whether this 'new' virus really is a different serotype or whether it is a variant of one of the four DENV serotypes already known. The good news is that this new variant has not yet established itself in the human transmission cycle. However, if it really is a new serotype this will have implications for the long-term control of dengue using vaccines currently under development.
    Matched MeSH terms: Dengue/virology*
  20. Fulltext Endogenous lentivirus in Malayan colugo (Galeopterus variegatus), a close relative of primates
    Hron T, Fábryová H, Pačes J, Elleder D
    Retrovirology, 2014;11:84.
    PMID: 25280529 DOI: 10.1186/s12977-014-0084-x
    A significant fraction of mammalian genomes is composed of endogenous retroviral (ERV) sequences that are formed by germline infiltration of various retroviruses. In contrast to other retroviral genera, lentiviruses only rarely form ERV copies. We performed a computational search aimed at identification of novel endogenous lentiviruses in vertebrate genomes.
    Matched MeSH terms: Mammals/virology*
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