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Displacement of predominant respiratory syncytial virus genotypes in Malaysia between 1989 and 2011

Khor CS, Sam IC, Hooi PS, Chan YF

Infect Genet Evol, 2013 Mar;14:357-60.
PMID: 23305888 DOI: 10.1016/j.meegid.2012.12.017

From 1989 to 2011 in Kuala Lumpur, Malaysia, multiple genotypes from both respiratory syncytial virus (RSV) subgroups were found co-circulating each year. RSV-A subgroup predominated in 12 out of 17years with the remaining years predominated by RSV-B subgroup. Local RSV strains exhibited temporal clustering with RSV strains reported in previous epidemiological studies. Every few years, the existing predominant genotype was replaced by a new genotype. The RSV-A genotypes GA2, GA5 and GA7 were replaced by NA1 and NA2, while BA became the predominant RSV-B genotype. A unique local cluster, BA12, was seen in 2009, and the recently-described ON1 genotype with 72-nt duplication emerged in 2011. Our findings will have important implications for future vaccine intervention.

Matched MeSH terms: Respiratory Syncytial Virus, Human/genetics*
Glycosylation is not necessary for recognition of the fusion glycoprotein domain of the human respiratory syncytial virus by a polyclonal antibody

Lim SH, Jahanshiri F, Jalilian FA, Rahim RA, Sekawi Z, Yusoff K

Acta Virol., 2010;54(3):181-7.
PMID: 20822310

Human respiratory syncytial virus (HRSV) is a leading pathogen causing lower respiratory tract infections in infants and young children worldwide. In line with the development of an effective vaccine against HRSV, a domain of the fusion (F) glycoprotein of HRSV was produced and its immunogenicity and antigenic properties, namely the effect of deficient glycosylation was examined. A His-tagged recombinant F (rF) protein was expressed in Escherichia coli, solubilized with 8 mol/l urea, purified by the Ni-NTA affinity chromatography and used for the raising of a polyclonal antibody in rabbits. The non-glycosylated rF protein proved to be a strong immunogen that induced a polyclonal antibody that was able to recognize also the glycosylated F1 subunit of native HRSV. The other way around, a polyclonal antibody prepared against the native HRSV was able to react with the rF protein. These results indicated that glycosylation was not necessary for the F domain aa 212-574 in order to be recognized by the specific polyclonal antibody.

Matched MeSH terms: Respiratory Syncytial Virus, Human/genetics
Fulltext Surveillance for respiratory syncytial virus and parainfluenza virus among patients hospitalized with pneumonia in Sarawak, Malaysia

Fieldhouse JK, Toh TH, Lim WH, Ting J, Ha SJ, Hii KC, et al.

PLoS One, 2018;13(8):e0202147.
PMID: 30110367 DOI: 10.1371/journal.pone.0202147

BACKGROUND: Respiratory syncytial virus (RSV) and parainfluenza virus (PIV) are frequent causes of pneumonia and death among children at Sibu and Kapit Hospitals in Sarawak, Malaysia.
OBJECTIVES: To determine the prevalence and risk factors for RSV subtypes A and B and PIV types 1-4 among patients hospitalized with pneumonia.
METHODS: In a cross-sectional, pilot study nasopharyngeal swabs were studied with real-time reverse transcription polymerase chain reaction assays. Concurrently, we helped Sibu and Kapit Hospitals adapt their first molecular diagnostics for RSV and PIV.
RESULTS: Of 129 specimens collected (June to July 2017), 39 tested positive for RSV-A (30.2%), two were positive for RSV B (1.6%), one was positive for PIV-3 (0.8%) and one was positive for PIV-4 (0.8%). No samples were positive for PIV-1 or PIV-2. Of the 39 RSV-A positive specimens, 46.2% were collected from children under one year of age and only 5.1% were from patients over the age of 18. A multivariable analysis found the odds of children <1 year of age testing positive for RSV-A were 32.7 (95% CI: 3.9, 276.2) times larger than >18 years of age, and the odds of patients hospitalized at Kapit Hospital testing positive for RSV-A were 3.2 (95% CI: 1.3, 7.8) times larger than patients hospitalized at Sibu Hospital.
CONCLUSION: This study found an unusually high prevalence of RSV-A among pneumonia patients admitted to the two hospitals. Subsequently, Sibu Hospital adapted the molecular assays with the goal of providing more directed care for such pneumonia patients.

Matched MeSH terms: Respiratory Syncytial Virus, Human/genetics
Development of two salmonella-based oral vaccines against human respiratory syncytial virus

Azizi Jalilian F, Yusoff K, Suhaimi S, Amini R, Sekawi Z, Jahanshiri F

J Biol Regul Homeost Agents, 2015 Jan-Mar;29(1):7-18.
PMID: 25864737

Human respiratory syncytial virus is the most common cause of bronchiolitis and other respiratory infections in infants and the elderly worldwide. We have developed two new oral vaccines using Salmonella typhi TY21a to carry and express the immunogenic epitopes of RSV fusion (F) and attachment (G) glycoproteins on its surface, separately. To evaluate the efficacy of the designed vaccines, BALB/c mice were orally immunized and then infected with RSV. Immune response analyses showed that cellmediated, mucosal and humoral immunity in the vaccinated mice were significantly enhanced compared to the control group. Both vaccines generated a balanced Th1/Th2 immune response which is crucial for efficiency of vaccines against RSV. Furthermore, histopathological examination proved that these vaccines were safe as they did not cause any Th2-associated adverse effects in the lungs of RSV-infected mice. The findings of this research suggest that Salmonella-F and Salmonella-G vaccine candidates may have strong potential to prevent RSV infection.

Matched MeSH terms: Respiratory Syncytial Virus, Human/genetics
Fulltext Comparative global epidemiology of influenza, respiratory syncytial and parainfluenza viruses, 2010-2015

Lam TT, Tang JW, Lai FY, Zaraket H, Dbaibo G, Bialasiewicz S, et al.

J Infect, 2019 10;79(4):373-382.
PMID: 31323249 DOI: 10.1016/j.jinf.2019.07.008

OBJECTIVES: To improve our understanding of the global epidemiology of common respiratory viruses by analysing their contemporaneous incidence at multiple sites.
METHODS: 2010-2015 incidence data for influenza A (IAV), influenza B (IBV), respiratory syncytial (RSV) and parainfluenza (PIV) virus infections were collected from 18 sites (14 countries), consisting of local (n = 6), regional (n = 9) and national (n = 3) laboratories using molecular diagnostic methods. Each site submitted monthly virus incidence data, together with details of their patient populations tested and diagnostic assays used.
RESULTS: For the Northern Hemisphere temperate countries, the IAV, IBV and RSV incidence peaks were 2-6 months out of phase with those in the Southern Hemisphere, with IAV having a sharp out-of-phase difference at 6 months, whereas IBV and RSV showed more variable out-of-phase differences of 2-6 months. The tropical sites Singapore and Kuala Lumpur showed fluctuating incidence of these viruses throughout the year, whereas subtropical sites such as Hong Kong, Brisbane and Sydney showed distinctive biannual peaks for IAV but not for RSV and PIV.
CONCLUSIONS: There was a notable pattern of synchrony of IAV, IBV and RSV incidence peaks globally, and within countries with multiple sampling sites (Canada, UK, Australia), despite significant distances between these sites.

Matched MeSH terms: Respiratory Syncytial Virus, Human/genetics