Displaying all 16 publications

Abstract:
Sort:
  1. Fulltext Zika virus and its potential re-emergence in Malaysia
    Sam JI, Chan YF, Vythilingam I, Wan Sulaiman WY
    Med J Malaysia, 2016 04;71(2):66-8.
    PMID: 27326944 MyJurnal
    Zika virus (ZIKV) has re-emerged to cause explosive epidemics in the Pacific and Latin America, and appears to be associated with severe neurological complications including microcephaly in babies. ZIKV is transmitted to humans by Aedes mosquitoes, principally Ae. aegypti, and there is historical evidence of ZIKV circulation in Southeast Asia. It is therefore clear that Malaysia is at risk of similar outbreaks. Local and international guidelines are available for surveillance, diagnostics, and management of exposed and infected individuals. ZIKV is the latest arbovirus to have spread globally beyond its initial restricted niche, and is unlikely to be the last. Innovative new methods for surveillance and control of vectors are needed to target mosquito-borne diseases as a whole.
    Matched MeSH terms: Zika Virus Infection/epidemiology*
  2. Isolation of Zika virus from Aedes aegypti mosquitoes in Malaysia
    Marchette NJ, Garcia R, Rudnick A
    Am J Trop Med Hyg, 1969 May;18(3):411-5.
    PMID: 4976739
    Matched MeSH terms: Zika Virus Infection/epidemiology
  3. Fulltext Phylogenetic surveillance of travel-related Zika virus infections through whole-genome sequencing methods
    Kamelian K, Montoya V, Olmstead A, Dong W, Harrigan R, Morshed M, et al.
    Sci Rep, 2019 Nov 11;9(1):16433.
    PMID: 31712570 DOI: 10.1038/s41598-019-52613-8
    In 2018, the World Health Organization identified the Zika virus (ZIKV) as a pathogen that should be prioritized for public health research due to its epidemic potential. In this study, whole-genome sequencing (WGS) of travel-acquired ZIKV infections was used to examine the limitations of phylogenetic analysis. WGS and phylogenetic analysis were performed to investigate geographic clustering of samples from five Canadians with travel-acquired ZIKV infections and to assess the limitations of phylogenetic analysis of ZIKV sequences using a phylogenetic cluster approach. Genomic variability of ZIKV samples was assessed and for context, compared with hepatitis C virus (HCV) samples. Phylogenetic analysis confirmed the suspected region of ZIKV infection for one of five samples and one sample failed to cluster with sequences from its suspected country of infection. Travel-acquired ZIKV samples depicted low genomic variability relative to HCV samples. A floating patristic distance threshold classified all pre-2000 ZIKV sequences into separate clusters, while only Cambodian, Peruvian, Malaysian, and South Korean sequences were similarly classifiable. While phylogenetic analysis of ZIKV data can identify the broad geographical region of ZIKV infection, ZIKV's low genomic variability is likely to limit precise interpretations of phylogenetic analysis of the origins of travel-related cases.
    Matched MeSH terms: Zika Virus Infection/epidemiology*
  4. Zika virus in Vietnam, Laos, and Cambodia: are there health risks for travelers?
    Dinh TC, Bac ND, Minh LB, Ngoc VTN, Pham VH, Vo HL, et al.
    Eur J Clin Microbiol Infect Dis, 2019 Sep;38(9):1585-1590.
    PMID: 31044332 DOI: 10.1007/s10096-019-03563-6
    Vietnam, Laos, and Cambodia have reported first cases of Zika virus (ZIKV) infection since 2010 (Cambodia) and 2016 (Vietnam and Laos). One case of ZIKV-related microcephaly was recognized among a hundred infected cases in these areas, raising a great concern about the health risk related to this virus infection. At least 5 cases of ZIKV infection among travelers to Vietnam, Laos, and Cambodia were recorded. It is noticeable that ZIKV in these areas can cause birth defects. This work aims to discuss the current epidemics of ZIKV in Vietnam, Laos, and Cambodia and update the infection risk of ZIKV for travelers to these areas.
    Matched MeSH terms: Zika Virus Infection/epidemiology*
  5. Fulltext Quantifying the risk of Zika virus spread in Asia during the 2015-16 epidemic in Latin America and the Caribbean: A modeling study
    Luo XS, Imai N, Dorigatti I
    Travel Med Infect Dis, 2020 01 26;33:101562.
    PMID: 31996323 DOI: 10.1016/j.tmaid.2020.101562
    BACKGROUND: No large-scale Zika epidemic has been observed to date in Southeast Asia following the 2015-16 Latin American and the Caribbean epidemic. One hypothesis is Southeast Asian populations' partial immunity to Zika.

    METHOD: We estimated the two conditions for a Zika outbreak emergence in Southeast Asia: (i) the risk of Zika introduction from Latin America and the Caribbean and, (ii) the risk of autochthonous transmission under varying assumptions on population immunity. We also validated the model used to estimate the risk of introduction by comparing the estimated number of Zika seeds introduced into the United States with case counts reported by the Centers for Disease Control and Prevention (CDC).

    RESULTS: There was good agreement between our estimates and case counts reported by the CDC. We thus applied the model to Southeast Asia and estimated that, on average, 1-10 seeds were introduced into Indonesia, Malaysia, the Philippines, Singapore, Thailand and Vietnam. We also found increasing population immunity levels from 0 to 90% reduced probability of autochthonous transmission by 40% and increasing individual variation in transmission further reduced the outbreak probability.

    CONCLUSIONS: Population immunity, combined with heterogeneity in transmission, can explain why no large-scale outbreak was observed in Southeast Asia during the 2015-16 epidemic.

    Matched MeSH terms: Zika Virus Infection/epidemiology*
  6. Zika virus infection and Guillain-Barré syndrome: a review focused on clinical and electrophysiological subtypes
    Uncini A, Shahrizaila N, Kuwabara S
    J Neurol Neurosurg Psychiatry, 2017 03;88(3):266-271.
    PMID: 27799296 DOI: 10.1136/jnnp-2016-314310
    In 2016, we have seen a rapid emergence of Zika virus-associated Guillain-Barré syndrome (GBS) since its first description in a French-Polynesian patient in 2014. Current evidence estimates the incidence of GBS at 24 cases per 100 000 persons infected by Zika virus. This will result in a sharp rise in the number of GBS cases worldwide with the anticipated global spread of Zika virus. A better understanding of the pathogenesis of Zika-associated GBS is crucial to prepare us for the current epidemic. In this review, we evaluate the existing literature on GBS in association with Zika and other flavivirus to better define its clinical subtypes and electrophysiological characteristics, demonstrating a demyelinating subtype of GBS in most cases. We also recommend measures that will help reduce the gaps in knowledge that currently exist.
    Matched MeSH terms: Zika Virus Infection/epidemiology
  7. Fulltext Zika virus in Asia
    Duong V, Dussart P, Buchy P
    Int J Infect Dis, 2017 Jan;54:121-128.
    PMID: 27939768 DOI: 10.1016/j.ijid.2016.11.420
    Zika virus (ZIKV) is an emerging mosquito-borne virus that was first isolated from a sentinel rhesus monkey in the Zika Forest in Uganda in 1947. In Asia, the virus was isolated in Malaysia from Aedes aegypti mosquitoes in 1966, and the first human infections were reported in 1977 in Central Java, Indonesia. In this review, all reported cases of ZIKV infection in Asia as of September 1, 2016 are summarized and some of the hypotheses that could currently explain the apparently low incidence of Zika cases in Asia are explored.
    Matched MeSH terms: Zika Virus Infection/epidemiology*
  8. Fulltext Entomological Surveillance Associated with Human Zika Cases in Miri Sarawak, Malaysia
    Ali R, Azmi RA, Wasi Ahmad N, Abd Hadi A, Muhamed KA, Rasli R, et al.
    Am J Trop Med Hyg, 2020 May;102(5):964-970.
    PMID: 32228777 DOI: 10.4269/ajtmh.19-0339
    Two confirmed human cases of Zika virus (ZIKV) were reported in the district of Miri, Sarawak, in 2016. Following that, a mosquito-based ZIKV surveillance study was conducted within 200-m radius from the case houses. Mosquito surveillance was conducted using five different methods, that is, biogents sentinel mosquito (BG) sentinel trap, modified sticky ovitrap, resting catch, larval surveillance, and conventional ovitrap. A total of 527 and 390 mosquito samples were obtained from the case houses in two localities, namely, Kampung Lopeng and Taman Shang Ri La, Miri, Sarawak, respectively. All mosquitoes collected were identified, which consisted of 11 species. Aedes albopictus, both the adult and larval stages, was the dominant species. Resting catch method obtained the highest number of adult mosquitoes (67%), whereas ovitrap showed the highest catch for larval mosquitoes (84%). Zika virus was detected in both adults and larvae of Ae. albopictus together with adults of Culex gelidus, and Culex quinquefasciatus using the real-time reverse transcriptase polymerase chain reaction (PCR) technique. It was noteworthy that Ae. albopictus positive with ZIKV were caught and obtained from four types of collection method. By contrast, Cx. gelidus and Culex quinquefasciatus adults collected from sticky ovitraps were also found positive with ZIKV. This study reveals vital information regarding the potential vectors of ZIKV and the possibility of transovarian transmission of the virus in Malaysia. These findings will be essentials for vector control program managers to devise preparedness and contingency plans of prevention and control of the arboviral disease.
    Matched MeSH terms: Zika Virus Infection/epidemiology*
  9. Fulltext Diagnosis and management of Guillain-Barré syndrome in ten steps
    Leonhard SE, Mandarakas MR, Gondim FAA, Bateman K, Ferreira MLB, Cornblath DR, et al.
    Nat Rev Neurol, 2019 Nov;15(11):671-683.
    PMID: 31541214 DOI: 10.1038/s41582-019-0250-9
    Guillain-Barré syndrome (GBS) is a rare, but potentially fatal, immune-mediated disease of the peripheral nerves and nerve roots that is usually triggered by infections. The incidence of GBS can therefore increase during outbreaks of infectious diseases, as was seen during the Zika virus epidemics in 2013 in French Polynesia and 2015 in Latin America. Diagnosis and management of GBS can be complicated as its clinical presentation and disease course are heterogeneous, and no international clinical guidelines are currently available. To support clinicians, especially in the context of an outbreak, we have developed a globally applicable guideline for the diagnosis and management of GBS. The guideline is based on current literature and expert consensus, and has a ten-step structure to facilitate its use in clinical practice. We first provide an introduction to the diagnostic criteria, clinical variants and differential diagnoses of GBS. The ten steps then cover early recognition and diagnosis of GBS, admission to the intensive care unit, treatment indication and selection, monitoring and treatment of disease progression, prediction of clinical course and outcome, and management of complications and sequelae.
    Matched MeSH terms: Zika Virus Infection/epidemiology
  10. Fulltext Genetic characterization of Zika virus strains: geographic expansion of the Asian lineage
    Haddow AD, Schuh AJ, Yasuda CY, Kasper MR, Heang V, Huy R, et al.
    PLoS Negl Trop Dis, 2012;6(2):e1477.
    PMID: 22389730 DOI: 10.1371/journal.pntd.0001477
    Zika virus (ZIKV) is a mosquito-borne flavivirus distributed throughout much of Africa and Asia. Infection with the virus may cause acute febrile illness that clinically resembles dengue fever. A recent study indicated the existence of three geographically distinct viral lineages; however this analysis utilized only a single viral gene. Although ZIKV has been known to circulate in both Africa and Asia since at least the 1950s, little is known about the genetic relationships between geographically distinct virus strains. Moreover, the geographic origin of the strains responsible for the epidemic that occurred on Yap Island, Federated States of Micronesia in 2007, and a 2010 pediatric case in Cambodia, has not been determined.
    Matched MeSH terms: Zika Virus Infection/epidemiology
  11. Zika virus, a cause of fever in Central Java, Indonesia
    Olson JG, Ksiazek TG, Suhandiman, Triwibowo
    Trans R Soc Trop Med Hyg, 1981;75(3):389-93.
    PMID: 6275577
    In 1977 and 1978 selected in-patients at the Tegalyoso Hospital, Klaten, Indonesia who had recent onsets of acute fever were serologically studied for evidence for alphavirus and flavivirus infections. A brief clinical history was taken and a check list of signs and symptoms was completed on admission. Acute and convalescent phase sera from 30 patients who showed evidence that a flavivirus had caused their illnesses were tested for neutralizing antibodies to several flaviviruses which occur in South-east Asia. Paired sera from seven patients demonstrated a fourfold rise in antibody titre from acute to convalescent phase. The most common clinical manifestations observed in this series of patients included high fever, malaise, stomach ache, dizziness and anorexia. None of the seven patients had headache or rash despite the fact that headache and rash had been associated with two of the three previously studied. The onsets of illness clustered toward the end of the rainy season when populations of Aedes aegypti, a probable vector in Malaysia, were most abundant.
    Matched MeSH terms: Zika Virus Infection/epidemiology*
  12. Fulltext Current concerns and perspectives on Zika virus co-infection with arboviruses and HIV
    Rothan HA, Bidokhti MRM, Byrareddy SN
    J Autoimmun, 2018 05;89:11-20.
    PMID: 29352633 DOI: 10.1016/j.jaut.2018.01.002
    Dissemination of vector-borne viruses, such as Zika virus (ZIKV), in tropical and sub-tropical regions has a complicated impact on the immunopathogenesis of other endemic viruses such as dengue virus (DENV), chikungunya virus (CHIKV) and human immunodeficiency virus (HIV). The consequences of the possible co-infections with these viruses have specifically shown significant impact on the treatment and vaccination strategies. ZIKV is a mosquito-borne flavivirus from African and Asian lineages that causes neurological complications in infected humans. Many of DENV and CHIKV endemic regions have been experiencing outbreaks of ZIKV infection. Intriguingly, the mosquitoes, Aedes Aegypti and Aedes Albopictus, can simultaneously transmit all the combinations of ZIKV, DENV, and CHIKV to the humans. The co-circulation of these viruses leads to a complicated immune response due to the pre-existence or co-existence of ZIKV infection with DENV and CHIKV infections. The non-vector transmission of ZIKV, especially, via sexual intercourse and placenta represents an additional burden that may hander the treatment strategies of other sexually transmitted diseases such as HIV. Collectively, ZIKV co-circulation and co-infection with other viruses have inevitable impact on the host immune response, diagnosis techniques, and vaccine development strategies for the control of these co-infections.
    Matched MeSH terms: Zika Virus Infection/epidemiology*
  13. Fulltext A reverse transcription loop-mediated isothermal amplification for broad coverage detection of Asian and African Zika virus lineages
    Teoh BT, Chin KL, Samsudin NI, Loong SK, Sam SS, Tan KK, et al.
    BMC Infect Dis, 2020 Dec 11;20(1):947.
    PMID: 33308203 DOI: 10.1186/s12879-020-05585-4
    BACKGROUND: Early detection of Zika virus (ZIKV) infection during the viremia and viruria facilitates proper patient management and mosquito control measurement to prevent disease spread. Therefore, a cost-effective nucleic acid detection method for the diagnosis of ZIKV infection, especially in resource-deficient settings, is highly required.

    METHODS: In the present study, a single-tube reverse transcription loop-mediated isothermal amplification (RT-LAMP) assay was developed for the detection of both the Asian and African-lineage ZIKV. The detection limit, strain coverage and cross-reactivity of the ZIKV RT-LAMP assay was evaluated. The sensitivity and specificity of the RT-LAMP were also evaluated using a total of 24 simulated clinical samples. The ZIKV quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay was used as the reference assay.

    RESULTS: The detection limit of the RT-LAMP assay was 3.73 ZIKV RNA copies (probit analysis, P ≤ 0.05). The RT-LAMP assay detected the ZIKV genomes of both the Asian and African lineages without cross-reacting with other arthropod-borne viruses. The sensitivity and specificity of the RT-LAMP assay were 90% (95% CI = 59.6-98.2) and 100% (95% CI = 78.5-100.0), respectively. The RT-LAMP assay detected ZIKV genome in 9 of 24 (37.5%) of the simulated clinical samples compared to 10 of 24 (41.7%) by qRT-PCR assay with a high level of concordance (κ = 0.913, P 

    Matched MeSH terms: Zika Virus Infection/epidemiology*
  14. Serological evidence of DENV, JEV, and ZIKV among the indigenous people (Orang Asli) of Peninsular Malaysia
    Khor CS, Mohd-Rahim NF, Hassan H, Tan KK, Zainal N, Teoh BT, et al.
    J Med Virol, 2020 08;92(8):956-962.
    PMID: 31814135 DOI: 10.1002/jmv.25649
    Dengue virus (DENV), Japanese encephalitis virus (JEV), and Zika virus (ZIKV) are mosquito-borne flavivirus of medical importance in tropical countries such as Malaysia. However, much remains unknown regarding their prevalence among the underserved indigenous people (Orang Asli) living in communities in the forest fringe areas of Peninsular Malaysia. Information on the prevalence of diseases is necessary to elevate the effectiveness of disease control and preventive measures. This study aimed to determine the seroprevalence of the three major flaviviruses among the Orang Asli and investigate the association between demographic factors and seropositivities. Sampling activities were conducted in the Orang Asli villages to obtain serum samples and demographic data from consenting volunteers. The presence of DENV, JEV, and ZIKV immunoglobulin G (IgG) antibodies in the sera were examined using commercial enzyme-linked immunosorbent assay kits. A focus reduction neutralization assay was performed to measure virus-specific neutralizing antibodies. A total of 872 serum samples were obtained from the Orang Asli volunteers. Serological assay results revealed that DENV IgG, JEV IgG, and ZIKV IgG seropositivities among the Orang Asli were at 4.9%, 48.4%, and 13.2%, respectively. Neutralizing antibodies (FRNT50 ≥ 1:40) against JEV and ZIKV were found in 86.7% and 100.0%, respectively, out of the samples tested. Positive serology to all three viruses corresponded significantly to the age of the volunteers with increasing seropositivity in older volunteers. Findings from the study suggest that Orang Asli are at significant risk of contracting JEV and ZIKV infections despite the lack of active transmission of the viruses in the country.
    Matched MeSH terms: Zika Virus Infection/epidemiology*
  15. Fulltext Serological Evidence of Zika Virus Infection in Febrile Patients and Healthy Blood Donors in Sabah, Malaysian Borneo, 2017-2018
    Ngwe Tun MM, Mori D, Sabri SB, Kugan O, Shaharom SB, John J, et al.
    Am J Trop Med Hyg, 2021 Nov 22;106(2):601-606.
    PMID: 34814105 DOI: 10.4269/ajtmh.21-0802
    Several Zika virus (ZIKV) seroprevalence studies have been conducted in Africa, Asia, Oceania, the Americas, and the Caribbean. However, studies on ZIKV seroprevalence are limited in Malaysia though several studies have shown that the disease is endemic in the Malaysian state of Sabah. To evaluate the seroprevalence of ZIKV infection, 818 serum samples were collected from febrile patients and healthy blood donors from the Kudat and Kota Kinabalu districts in Sabah from 2017 to 2018. They were screened for ZIKV infection by IgM and IgG ELISA, and positive ZIKV IgM samples were subjected to a 90% neutralization test for confirmation. Twenty-four (6% [95% CI 4 to 8]) confirmed and two (0.5% [95% CI 0.13 to 1.8]) probable ZIKV infections were detected among 400 febrile illness patients. Of 418 healthy blood donor samples, six (1.4% [95% CI 0.65 to 3]) were determined as confirmed ZIKV infections and six (1.4% [95% CI 0.65 to 3]) indicated probable ZIKV infection. This is the first study on the seroprevalence of ZIKV infections among patients and healthy blood donors in Sabah. Compared with previous studies in Malaysia, this study shows that the incidence of ZIKV infection has increased. It also suggests that a sero-surveillance system is essential to determine the circulation of ZIKV in Sabah, Malaysia.
    Matched MeSH terms: Zika Virus Infection/epidemiology
  16. Fulltext Vector competence of Aedes aegypti, Culex tarsalis, and Culex quinquefasciatus from California for Zika virus
    Main BJ, Nicholson J, Winokur OC, Steiner C, Riemersma KK, Stuart J, et al.
    PLoS Negl Trop Dis, 2018 Jun;12(6):e0006524.
    PMID: 29927940 DOI: 10.1371/journal.pntd.0006524
    Zika virus (ZIKV) has emerged since 2013 as a significant global human health threat following outbreaks in the Pacific Islands and rapid spread throughout South and Central America. Severe congenital and neurological sequelae have been linked to ZIKV infections. Assessing the ability of common mosquito species to transmit ZIKV and characterizing variation in mosquito transmission of different ZIKV strains is important for estimating regional outbreak potential and for prioritizing local mosquito control strategies for Aedes and Culex species. In this study, we evaluated the laboratory vector competence of Aedes aegypti, Culex quinquefasciatus, and Culex tarsalis that originated in areas of California where ZIKV cases in travelers since 2015 were frequent. We compared infection, dissemination, and transmission rates by measuring ZIKV RNA levels in cohorts of mosquitoes that ingested blood meals from type I interferon-deficient mice infected with either a Puerto Rican ZIKV strain from 2015 (PR15), a Brazilian ZIKV strain from 2015 (BR15), or an ancestral Asian-lineage Malaysian ZIKV strain from 1966 (MA66). With PR15, Cx. quinquefasciatus was refractory to infection (0%, N = 42) and Cx. tarsalis was infected at 4% (N = 46). No ZIKV RNA was detected in saliva from either Culex species 14 or 21 days post feeding (dpf). In contrast, Ae. aegypti developed infection rates of 85% (PR15; N = 46), 90% (BR15; N = 20), and 81% (MA66; N = 85) 14 or 15 dpf. Although MA66-infected Ae. aegypti showed higher levels of ZIKV RNA in mosquito bodies and legs, transmission rates were not significantly different across virus strains (P = 0.13, Fisher's exact test). To confirm infectivity and measure the transmitted ZIKV dose, we enumerated infectious ZIKV in Ae. aegypti saliva using Vero cell plaque assays. The expectorated plaque forming units PFU varied by viral strain: MA66-infected expectorated 13±4 PFU (mean±SE, N = 13) compared to 29±6 PFU for PR15-infected (N = 13) and 35±8 PFU for BR15-infected (N = 6; ANOVA, df = 2, F = 3.8, P = 0.035). These laboratory vector competence results support an emerging consensus that Cx. tarsalis and Cx. quinquefasciatus are not vectors of ZIKV. These results also indicate that Ae. aegypti from California are efficient laboratory vectors of ancestral and contemporary Asian lineage ZIKV.
    Matched MeSH terms: Zika Virus Infection/epidemiology
Related Terms
Filters
Contact Us

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

External Links