BackgroundThe co-circulation of 4 DENV serotypes in geographically expanding area, has resulted in increasing occurrence of DENV co-infections. However, studies assessing the clinical impact of DENV co-infections have been scarce and have involved small number of patients. This study explores the impact of DENV co-infection on clinical manifestations and laboratory parameters.MethodsThis retrospective study involved consecutive hospitalized patients with non-structural protein 1 (NS1) antigen positivity during an outbreak (Jan to April 2014). Multiplex RT-PCR was performed directly on NS1 positive serum samples to detect and determine the DENV serotypes. All PCR-positive serum samples were inoculated onto C6/36 cells. Multiplex PCR was repeated on the supernatant of the first blind passage of the serum-infected cells. Random samples of supernatant from the first passage of C6/36 infected cells were subjected to whole genome sequencing. Clinical and laboratory variables were compared between patients with and without DENV co-infections.ResultsOf the 290 NS1 positive serum samples, 280 were PCR positive for DENV. Medical notes of 262 patients were available for analysis. All 4 DENV serotypes were identified. Of the 262 patients, forty patients (15.3 %) had DENV co-infections: DENV-1/DENV-2(85 %), DENV-1/DENV-3 (12.5 %) and DENV-2/DENV-3 (2.5 %). Another 222 patients (84.7 %) were infected with single DENV serotype (mono-infection), with DENV- 1 (76.6 %) and DENV- 2 (19.8 %) predominating. Secondary dengue infections occurred in 31.3 % patients. Whole genome sequences of random samples representing DENV-1 and DENV-2 showed heterogeneity amongst the DENVs.Multivariate analysis revealed that pleural effusion and the presence of warning signs were significantly higher in the co-infected group, both in the overall and subgroup analysis. Diarrhoea was negatively associated with co-infection. Additionally, DENV-2 co-infected patients had higher frequency of patients with severe thrombocytopenia (platelet count < 50,000/mm3), whereas DENV-2 mono-infections presented more commonly with myalgia. Elevated creatinine levels were more frequent amongst the co-infected patients in univariate analysis. Haemoconcentration and haemorrhagic manifestations were not higher amongst the co-infected patients. Serotypes associated with severe dengue were: DENV-1 (n = 9), DENV-2 (n = 1), DENV-3 (n = 1) in mono-infected patients and DENV-1/DENV-2 (n = 5) and DENV-1/DENV-3 (n = 1) amongst the co-infected patients.ConclusionDENV co-infections are not uncommon in a hyperendemic region and co-infected patients are skewed towards more severe clinical manifestations compared to mono-infected patients.

Severe thrombocytopenia is common in dengue virus (DENV) infections. However, studies focusing on the role of profound thrombocytopenia (PT) (nadir platelet counts ≤ 20 000/mm) in DENV infections are scarce. This study aims to identify the associated features and outcome of DENV patients with PT. It involves 237 adult hospitalized patients who were DENV PCR positive. The presence of comorbidity (AOR = 4.625; 95% CI = 1.113-19.230), higher admission hematocrit (AOR = 1.213; 95% CI = 1.067-1.379), lower admission albumin (AOR = 0.870; 95% CI = 0.766-0.988) and lower admission platelets (AOR = 0.980; 95% CI = 0.969-0.991) was associated with platelets ≤ 20 000/mm in multivariate logistic regression. PT was not affected by DENV serotypes, coinfections and secondary DENV infections. Patients with PT had significantly higher risk of experiencing warning signs (AOR = 3.709, 95% CI = 1.089-12.634) and longer hospital stay (AOR = 1.943, 95% CI = 1.010-3.774). However, severe dengue disease, hemorrhagic manifestations and need for intensive care were not significantly associated with PT.

Background As a result of the COVID-19 pandemic, changes in data collection methods have been introduced in research to ensure continuity despite physical distancing and lockdown restrictions. However, little is currently known about the potential differences in information collected using these traditional face-to-face methods compared to the incorporation of virtual methods to address the above, particularly in studies involving older adults. Aims Our objectives were, therefore, to compare data collected during the pandemic using hybrid methods from older individuals participating in falls research to that collected through traditional face-to-face methods. Methods Participants comprised of individuals recruited to two fall studies which hurdled the start of the COVID-19 pandemic. Both studies recruited individuals aged 60 years and over with at least one fall in the past 12 months, and controls with no history of falls in the past 12 months. Pre-pandemic, individuals were interviewed face-to-face exclusively, those interviews after the start of the pandemic were conducted virtually with physical assessments conducted face-to-face to minimize physical contact. Cognitive, physical, and psychological status were determined using the visual cognitive assessment tool (VCAT), timed-up-and-go (TUG), functional reach (FR), handgrip strength (HGS), and the 21-item depression, anxiety and stress scale (DASS-21). In addition quality of life, physical activity and social participation were also measured. Results Of the 145 participants (median age (interquartile range, IQR) of 73.5 (67-81) years), 69 (47.6%) were interviewed face-to-face, while 76 (53.4%) were assessed using a hybrid method. Participants in both groups had similar age, gender, ethnic breakdown, marital status, education levels, anthropometric measurements, and medication burden. More face-to-face participants had hypertension and fall compared to hybrid participants Differences were observed in presence of fall characteristics, with fewer fallers seeing a doctor and more fallers attending the emergency department after the start of the pandemic. After adjustment for baseline differences, participants interviewed using hybrid status had lower depression scores (odds ratio, OR (95% confidence interval, CI)=0.29(0.14-0.61) and stress scores (OR(95%CI)=0.33(0.15-0.72)), but greater fear of falling (OR(95%CI)=2.16(1.04-4.48)) and reduced social participation (OR(95%CI)=2.64(1.20-5.79)). Conclusion Alterations in recruitment and data collection methods to overcome pandemic restrictions should take into consideration potential differences in individuals who agree to participate as well as the influence of major life events on the psychological status of participants.