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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.

In 2019, an outbreak of chikungunya virus infection occurred in Mandalay, Myanmar, and 3.2% of blood donors and 20.5% of patients who were children were confirmed as being infected. The prevalence rate was up to 6.3% among blood donors. The East Central/ South African genotype was predominantly circulating during this outbreak., Emerging Infectious Diseases, 26(11), pp.2741-2745; 2020

BackgroundZika virus (ZIKV) is a mosquito-borne flavivirus. Outbreaks of ZIKV infection have occurred in Africa, Southeast Asia, the Pacific Islands, the Americas and the Caribbean. Although most ZIKV infections are asymptomatic, cases of neurological manifestations have been described. The aim of the present study was to identify the prevalence of ZIKV infection among the asymptomatic persons in Myanmar in 2018.MethodsA total of 284 serum samples from apparently healthy persons were collected from Yangon, Myanmar in 2018. They were analysed for ZIKV infection by immunoglobulin M (IgM) capture enzyme-linked immunosorbent assay (ELISA), IgG indirect ELISA, 50% focus reduction neutralization test, real-time reverse transcription polymerase chain reaction (RT-PCR) and conventional RT-PCR.ResultsOf the 284 apparently healthy persons, 31.3% were positive for the presence of IgM against ZIKV and 94.3% were positive for anti-flavivirus IgG. Among the ZIKV IgM-positive samples, we confirmed ZIKV infection in 15.8% of asymptomatic persons by neutralization test and real-time RT-PCR.ConclusionsWe conclude that ZIKV infection was increasing among asymptomatic persons in the same area in Myanmar during 2018 compared with 2017. It is highly recommended to strengthen the surveillance system for ZIKV to prevent possible outbreaks.

A 57-year-old woman with a history of previous bilateral breast polyacrylamide hydrogel injection presented for 18F-FDG PET/CT imaging to investigate recurrent retroperitoneal liposarcoma. Incidental symmetrical FDG-positive accumulation was noted in the bilateral axillae tracking between the interpectoral planes. The finding is consistent with a chronic inflammatory process secondary to the migration of the polyacrylamide hydrogel injections.

Dengue virus (DENV) infection is a major cause of morbidity and mortality in Vietnam, and the incidence is higher and more consistent in the southern part of the country. This study investigated the circulation of DENV serotypes, viremia levels, immunological status, and cytokine levels, with disease severities among children infected in 2017 in Ho Chi Minh City, Southern Vietnam. Acute and convalescent serum samples were collected from clinically diagnosed dengue children. They were confirmed to have DENV infection by NS1 antigen, IgM and IgG ELISAs, virus isolation, and conventional and real-time RT-PCR. Measurement of 10 cytokine levels was performed in the serum samples. All the children were dengue IgM positive; 28% and 72% of them had primary and secondary DENV infections, respectively, whereas 54% of those with secondary infection were children with dengue with warning signs and with severe dengue. Any or mixed infection of the four serotypes of DENV RNA was detected in 58 children. Twenty DENV strains (DENV-1 = 16 and DENV-4 = 4) were isolated. Levels of IFN-γ, TNF-α, MCP-1, IL-10, and IL-6 were significantly higher in severe dengue cases. We report the predominance of DENV-1 over other serotypes in the 2017 dengue outbreak in Southern Vietnam. Our data showed that cytokine expressions were correlated with dengue pathogenesis and may help in identifying an effective therapeutic strategy., The American journal of tropical medicine and hygiene, 102(6), pp.1217-1225; 2020

Background Sri Lanka experienced its largest dengue outbreak in 2017 with more than 185,000 dengue cases including at least 250 fatalities. Objectives Our study aimed to characterize the clinical, immunological and virological features of confirmed dengue patients in Sri Lanka during the outbreak in 2017 when unusual manifestations of severe dengue were observed. Study design Sera from 295 patients who were admitted to Teaching Hospital Kandy, Kandy, Sri Lanka between March 2017- January 2018 were subjected to NS1 antigen, IgM and IgG ELISAs, virus isolation, conventional and real time RT-PCR and next generation sequencing. Results Primary and secondary infections were detected in 48.5 % and 51.5 % of the study population, respectively. Two hundred twenty five DENV strains were isolated (219 DENV-2, one DENV-3, two DENV-4, two mixed infections of DENV-2 and -3 and one mixed infection of DENV-2 and -4). Unusual and severe manifestations such as encephalitis, encephalopathy, liver failure, kidney failure, myocarditis, Guillain–Barre syndrome and multi-organ failure were noted in 44 dengue patients with 11 deaths. The viraemia levels in patients with primary infection and unusual manifestations were significantly higher compared to those in patients with secondary infection. A new clade of DENV-2 Cosmopolitan genotype strains was observed with the strains closely related to those from China, Malaysia, Indonesia, Singapore and Taiwan. Conclusions The new clade of DENV-2 cosmopolitan genotype observed in Sri Lanka in 2017 caused an unprecedented, severe dengue outbreak. The emergence of DENV-3 and DENV-4 in the 2017 outbreak might cause future outbreaks in Sri Lanka.

Dyslipidaemia and increased oxidative stress have been reported in severe obstructive sleep apnea, and both may be related to the development of cardiovascular disease. We have previously shown in a randomized crossover study in patients with moderate to severe obstructive sleep apnea that therapeutic continuous positive airway pressure treatment for 8 weeks improved postprandial triglycerides and total cholesterol when compared with sham continuous positive airway pressure. From this study we have now compared the effect of 8 weeks of therapeutic continuous positive airway pressure and sham continuous positive airway pressure on oxidative lipid damage and plasma lipophilic antioxidant levels. Unesterified cholesterol, esterified unsaturated fatty acids (cholesteryl linoleate: C18:2; and cholesteryl arachidonate: C20:4; the major unsaturated and oxidizable lipids in low-density lipoproteins), their corresponding oxidized products [cholesteryl ester-derived lipid hydroperoxides and hydroxides (CE-O(O)H)] and antioxidant vitamin E were assessed at 20:30 hours before sleep, and at 06:00 and 08:30 hours after sleep. Amongst the 29 patients completing the study, three had incomplete or missing [CE-O(O)H] data. The mean apnea -hypopnoea index, age and body mass index were 38 per hour, 49 years and 32 kg m(-2) , respectively. No differences in lipid-based oxidative markers or lipophilic antioxidant levels were observed between the continuous positive airway pressure and sham continuous positive airway pressure arms at any of the three time-points [unesterified cholesterol 0.01 mm, P > 0.05; cholesteryl linoleate: C18:2 0.05 mm, P > 0.05; cholesteryl arachidonate: C20:4 0.02 mm, P = 0.05; CE-O(O)H 2.5 nm, P > 0.05; and lipid-soluble antioxidant vitamin E 0.03 μm, P > 0.05]. In this study, accumulating CE-O(O)H, a marker of lipid oxidation, does not appear to play a role in oxidative stress in obstructive sleep apnea. National Health and Medical Research Council project grant 301936

The Gulf of Thailand is characterized by shallow-water depth wells with bottomhole static temperature ranging from 240 to more than 420°F. These wells are drilled to an average of 12,000 ft MD and 9,000 ft TVD with a fast paced-batch drilling strategy. Most cement jobs are done offline, and on the surface section can be as frequent as 6 jobs per day. With multiple rigs, operators can require more than 100 cementing operations per month and cement volumes as high as 18,000 bbl. This efficient operations environment creates a demand for a logistically and operationally simple cement system that can be applied in all well sections and across the full range of expected temperatures. An advanced, lightweight seawater-based cementing concept was tested for this application. This new cementing system uses a single blend with only 3 to 4 primary liquid additives (including a stable, high-temperature, multi-functional polymer) to adjust all primary cement jobs for the entire wellbore. A sophisticated lab testing program was conducted for the innovative cementing concept according to the required demands on cement slurry design given the harsh wellbore conditions in the Gulf of Thailand. Tests revealed that the developed cementing systems meet all well requirements despite low densities of 13.3 to 14.0 ppg with high water content. This advanced cementing system was introduced in 2011 and has gradually been used on all wells since then – to date more than 500 wells in the Gulf of Thailand. In addition to improving logistics, use of the system has enhanced cement bond quality in production tubing cementing jobs. This improvement also reduced pay at risk due to insufficient cement isolation. This is evident in the whole range of well temperatures.

The Gulf of Thailand is characterized by shallow-water depth wells with bottomhole static temperature ranging from 240 to more than 420°F. These wells are drilled to an average of 12,000 ft MD and 9,000 ft TVD with a fast paced-batch drilling strategy. Most cement jobs are done offline, and on the surface section can be as frequent as 6 jobs per day. With multiple rigs, operators can require more than 100 cementing operations per month and cement volumes as high as 18,000 bbl. This efficient operations environment creates a demand for a logistically and operationally simple cement system that can be applied in all well sections and across the full range of expected temperatures. An advanced, lightweight seawater-based cementing concept was tested for this application. This new cementing system uses a single blend with only 3 to 4 primary liquid additives (including a stable, high-temperature, multi-functional polymer) to adjust all primary cement jobs for the entire wellbore. A sophisticated lab testing program was conducted for the innovative cementing concept according to the required demands on cement slurry design given the harsh wellbore conditions in the Gulf of Thailand. Tests revealed that the developed cementing systems meet all well requirements despite low densities of 13.3 to 14.0 ppg with high water content. This advanced cementing system was introduced in 2011 and has gradually been used on all wells since then – to date more than 500 wells in the Gulf of Thailand. In addition to improving logistics, use of the system has enhanced cement bond quality in production tubing cementing jobs. This improvement also reduced pay at risk due to insufficient cement isolation. This is evident in the whole range of well temperatures.