Association between quality of sleep and screen time during the COVID-19 outbreak among adolescents in the United Arab Emirates.

The COVID-19 pandemic had a major impact on people of all ages. Adolescents' exposure to online learning is linked to excessive screen time on digital devices, which leads to poor sleep quality. This study aimed to investigate the association between screen time on different electronic devices and sleep quality among adolescents in the United Arab Emirates. This study was based on a self-reported questionnaire, which was administered online to school-aged adolescents (aged 12-19 years). The multicomponent questionnaire collected information on sociodemographic characteristics, sleep quality using the Pittsburgh Sleep Quality Index (PSQI), and screen time (minutes) on TV, TV-connected devices, laptops, smartphones, and tablets on weekdays, weeknight, and weekends using the Screen Time Questionnaire (STQ). Univariate and multivariate analyses were used to identify factors correlated with poor sleep quality. A total of 1720 adolescents were recruited from private and public schools (mean age 14.6 ± 1.97 years). The mean PSQI score was 8.09 ± 3.37, and 74.3% of participants reported poor sleep (cutoff score >5). Mean scores were highest for the sleep latency (1.85 ± 0.97) and sleep disturbance (1.56 ± 0.62) domains. The highest STQ score was observed for smartphones, with a median screen time of 420 min on weekdays and 300 min on weekends. Screen time related to smartphones on weekends (p = 0.003) and increased screen time in bed (p < 0.001) were significantly associated with poor sleep. Our results confirmed the correlation between sleep and screen time in adolescents. The results may inform educational polices that target screen time and sleep among adolescents during and after the COVID-19 pandemic.

A survey of visual impairment and blindness in children attending eight schools for the blind in Myanmar: An update.

Purpose: To determine the causes of visual impairment (VI) and blindness among children in schools for the blind in Myanmar; to identify the avoidable causes of VI and blindness; to provide spectacles, low-vision aids, and ophthalmic treatment where indicated; to provide an update of the 2007 survey performed and identify any major epidemiological changes. Methods: Two hundred and ninety children under 16 years of age from all eight schools for the blind in Myanmar were examined and the data entered into the World Health Organization Prevention of Blindness Examination Record for Childhood Blindness. Results: In total, 271 children (93.4%) were blind (visual acuity [VA] <3/60 in the better eye) and 15 (5.17%) had severe visual impairment (SVI = VA <6/60 to 3/60 in the better eye). Most children had whole globe as the major anatomical site of SVI or blindness (105, 36.6%). The cause was unknown in the majority of these (155, 54.0%). One hundred and twelve children had avoidable causes of blindness and SVI (39.0%). Forty children (13.9%) required an optical device and 10.1% required surgical or medical attention, with a potential for visual improvement through intervention in 3.48%. Conclusion: In all, 39.0% of children had potentially avoidable causes of SVI and blindness with cataracts and measles being the commonest causes. This follow-up survey performed after the first one completed in Myanmar in 2007 demonstrates a change in the major site of abnormality from the cornea to whole globe and a reduction in avoidable blindness but highlights the ongoing burden of measles.

Assessment of global and regional left ventricular function using 64-slice multislice computed tomography and 2D echocardiography: a comparison with cardiac magnetic resonance.

OBJECTIVES: To compare the assessment of global and regional left ventricular (LV) function using 64-slice multislice computed tomography (MSCT), 2D echocardiography (2DE) and cardiac magnetic resonance (CMR). METHODS: Thirty-two consecutive patients (mean age, 56.5+/-9.7 years) referred for evaluation of coronary artery using 64-slice MSCT also underwent 2DE and CMR within 48h. The global left ventricular function which include left ventricular ejection fraction (LVEF), left ventricular end diastolic volume (LVdV) and left ventricular end systolic volume (LVsV) were determine using the three modalities. Regional wall motion (RWM) was assessed visually in all three modalities. The CMR served as the gold standard for the comparison between 64-slice MSCT with CMR and 2DE with CMR. Statistical analysis included Pearson correlation coefficient, Bland-Altman plots and kappa-statistics. RESULTS: The 64-slice MSCT agreed well with CMR for assessment of LVEF (r=0.92; p<0.0001), LVdV (r=0.98; p<0.0001) and LVsV (r=0.98; p<0.0001). In comparison with 64-slice MSCT, 2DE showed moderate correlation with CMR for the assessment of LVEF (r=0.84; p<0.0001), LVdV (r=0.83; p<0.0001) and LVsV (r=0.80; p<0.0001). However in RWM analysis, 2DE showed better accuracy than 64-slice MSCT (94.3% versus 82.4%) and closer agreement (kappa=0.89 versus 0.63) with CMR. CONCLUSION: 64-Slice MSCT correlates strongly with CMR in global LV function however in regional LV function 2DE showed better agreement with CMR than 64-slice MSCT.

Validation of Brunei's Malay EQ-5D Questionnaire in Patients with Type 2 Diabetes.

BACKGROUND: The Malay spoken in Brunei a South East Asian country where Malay is the national language is distinctive and different from Malay spoken in Malaysia, Singapore and Indonesia. This study aimed to develop a Brunei Malay version of the 5-level EQ-5D questionnaire (EQ-5D-5L) and to assess its psychometric properties among patients with type 2 diabetes mellitus (T2DM). METHODS: The Brunei Malay EQ-5D-5L was developed by culturally adapting two existing Malay versions. A total of 154 Bruneians with T2DM completed the questionnaire in two different points of time with one week apart. Known-groups validity of the utility-based EQ-5D-5L index and visual analogue scale (EQ-VAS) was evaluated by comparing subgroups of patients known to differ in health status. Test-retest reliability was assessed using the intraclass correlation coefficient (ICC) or Cohen's kappa. RESULTS: As hypothesized, patients known to have 'better' health had higher EQ-5D-5L index scores than those having 'worse' health in all 7 known-groups comparisons. The hypothesized difference in the EQ-VAS scores was observed in only 4 of the 7 known-groups comparisons. Kappa values ranged from 0.206 to 0.446 for the EQ-5D-5L items; the ICC value for the EQ-5D-5L index and EQ-VAS was 0.626 and 0.521, respectively. CONCLUSIONS: The utility-based EQ-5D-5L index appears to be valid and reliable for measuring the health of Brunei patients with T2DM. The validity of the EQ-VAS in Brunei requires further investigation.

Knowledge, attitudes and practice survey on Zika virus infection among pregnant women in Brunei Darussalam

Objective:To assess the knowledge, attitudes, and practices (KAP) on Zika virus infection among pregnant women in Brunei Darussalam by a cross-sectional survey.Methods:Between February and June 2017, we recruited 234 pregnant women from all government healthcare centres at Brunei-Muara district, using a modified systematic sampling approach. A pre-tested and self-administered questionnaire was used and data analysis was conducted using descriptive statistics and multiple logistic regression analyses.Results:The study participants were mainly Malay (87.2%) and their mean age was 28.0 years. The median knowledge score was 13, out of a possible score of 28. Most participants (92.7%) knew that Zika virus was transmitted by mosquito bites whereas some (34.6%) knew that sexual transmission was also possible. Media (radio, television or newspapers) was the preferred source of updated information on Zika virus, followed by healthcare workers (44.0%), government announcements (43.2%), and social media (38.0%). Pregnant women who were 25 years old or older [Adj. OR=3.62 (95% CI: 1.57, 9.51)], not Malays [Adj. OR=3.32 (95% CI: 1.35, 8.55)], and had an average monthly household income of more than BND $3 000 [Adj. OR=4.06 (95% CI: 1.81, 19.44)] were more likely to score higher for knowledge on Zika virus. The median prevention practice score was 23, out of a possible score of 36. Most participants reported wearing covering clothes (98.3%) and kept their living surroundings clean (99.6%). Most participants (88.0%) agreed that Zika is an important issue in their community.Conclusion:We found a lack of knowledge on Zika virus infection among pregnant women attending government maternal and child healthcare centres in Brunei Darussalam, in particular that Zika virus can be sexually transmitted. Such information could be well disseminated at the healthcare centre level. Health literacy studies should be conducted to understand the facilitators and barriers of KAP on Zika virus infection among pregnant women.

Knowledge, attitudes and practice survey on Zika virus infection among pregnant women in Brunei Darussalam

Objective: To assess the knowledge, attitudes, and practices (KAP) on Zika virus infection among pregnant women in Brunei Darussalam by a cross-sectional survey. Methods: Between February and June 2017, we recruited 234 pregnant women from all government healthcare centres at Brunei-Muara district, using a modified systematic sampling approach. A pre-tested and self-administered questionnaire was used and data analysis was conducted using descriptive statistics and multiple logistic regression analyses. Results: The study participants were mainly Malay (87.2%) and their mean age was 28.0 years. The median knowledge score was 13, out of a possible score of 28. Most participants (92.7%) knew that Zika virus was transmitted by mosquito bites whereas some (34.6%) knew that sexual transmission was also possible. Media (radio, television or newspapers) was the preferred source of updated information on Zika virus, followed by healthcare workers (44.0%), government announcements (43.2%), and social media (38.0%). Pregnant women who were 25 years old or older [Adj. OR=3.62 (95% CI: 1.57, 9.51)], not Malays [Adj. OR=3.32 (95% CI: 1.35, 8.55)], and had an average monthly household income of more than BND $3 000 [Adj. OR=4.06 (95% CI: 1.81, 19.44)] were more likely to score higher for knowledge on Zika virus. The median prevention practice score was 23, out of a possible score of 36. Most participants reported wearing covering clothes (98.3%) and kept their living surroundings clean (99.6%). Most participants (88.0%) agreed that Zika is an important issue in their community. Conclusion: We found a lack of knowledge on Zika virus infection among pregnant women attending government maternal and child healthcare centres in Brunei Darussalam, in particular that Zika virus can be sexually transmitted. Such information could be well disseminated at the healthcare centre level. Health literacy studies should be conducted to understand the facilitators and barriers of KAP on Zika virus infection among pregnant women.

Reporting Statistical Results in Medical Journals

Statistical editors of the Malaysian Journal of Medical Sciences (MJMS) must go through many submitted manuscripts, focusing on the statistical aspect of the manuscripts. However, the editors notice myriad styles of reporting the statistical results, which are not standardised among the authors. This could be due to the lack of clear written instructions on reporting statistics in the guidelines for authors. The aim of this editorial is to briefly outline reporting methods for several important and common statistical results. It will also address a number of common mistakes made by the authors. The editorial will serve as a guideline for authors aiming to publish in the MJMS as well as in other medical journals.

An investigation of inter-examiner reproducibility in recording malocclusion parameters during orthodontic epidemiologic studies

This study assesses inter-examiner reproducibility in recording various malocclusion parameters and Index of Orthodontic Treatment Need (IOTN) grade during patient examination by utilising the kappa statistic. Five previously calibrated orthodontists clinically examined 233 non-orthodontically treated schoolchildren aged 14-17 years for recording various malocclusion parameters. The examination was repeated twice, thirty days apart and precluded the use of study-models or radiographs. Although good inter-examiner reproducibility was observed in recording incisor class, IOTN dental health grade, type of posterior crossbite, and excellent for parameters with absolute criteria like erupted supernumeraries, etc, substantial examiner variation resulted in only fair reproducibility for recording IOTN esthetic category, canine class, overbite category, traumatic overbite and upper centre-line shift of two millimetres or more from the facial midline. Reproducibility for detecting occlusal displacement in the presence of crossbite was poor, and kappa statistic was incalculable for recording openbite and number of upper incisors rotated 30° or more. Kappa was also incalculable for recording IOTN dental health subcategory due to the creation of asymmetric tables caused by rarely chosen subcategory options. Despite prior agreement between previously calibrated examiners on evaluation criteria, detection of certain malocclusion parameters during an epidemiological examination can prove to be challenging. Epidemiological studies that report on prevalence of malocclusion in the population should always report on the kappa reproducibility, especially if the study is carried out by multiple examiners.

Cholecystectomy rate following endoscopic biliary interventions

Introduction: Gallstones disease is a common disorder and symptomatic disease is usually managed with surgery while those with common bile duct stones are usually managed with endoscopic intervention before proceeding to surgery. This study was intended to assess the rate of cholecystectomy among patients who had undergone ERC interventions, the reasons for not proceeding to cholecystectomy and related complications. Materials and Methods: Patients who had intact gallbladder and had undergone ERC for stones related complications over a two year period were retrospectively identified from the Endoscopic Unit Registry. Detailed case note reviews were conducted. Results: The overall cholecystectomy rate post-ERC interventions was 36.9% (48/130). Cholecystectomy was offered to 59.2% (n=77) and the uptake was only 58.4% (n=45/77). Among those who agreed for cholecystectomy, 11.1% (n=5/45) failed to turn up for their scheduled surgery. Three patients (6.7%) had symptoms recurrence before their scheduled surgery: two subsequently underwent cholecystectomy without ERC intervention and one who was pregnant was managed conservatively with holecystectomy. Among the patients who had declined cholecystectomy, 18.8% (n=6/32) had symptoms recurrence. Four patients required repeat ERC interventions and eventually all had cholecystectomy subsequently. The most common reason for declining cholecystectomy was 'not keen' and already asymptomatic (46.9%, n=15/32). Among patients who were not offerred cholecystectomy (n=53/130), symptoms recurrence occurred in 15.2% (n=7/53). Four patients required repeat ERC interventions and three subsequently underwent cholecystectomy. Conclusions: The cholecystectomy rate remains low after ERC interventions. Recurrence of symptoms necessating re-interventions occurred in patients offerred and not offerred cholecystectomy. The uptake rate should be improved and delay to cholecystectomy should be reduced to avoid symptoms recurrence. Patients not undergoing interventions should be advised regarding symptoms recurrence and should be monitored.

Dental caries experience and treatment needs in the mixed dentition in North East Malaysia

Dental caries is an important community dental health problem with limited studies in the mixed dentition stage. The aim of this study was to determine the caries prevalence and treatment needs among 7- 9 year old school children in Kelantan which is situated in North East Malaysia. A retrospective dental record review of fully documented dental records belonging to primary school children attending a paediatric dental clinic was conducted. Dental caries was recorded using dmft index and DMFT index for deciduous teeth and permanent teeth respectively. Three hundred and nineteen dental records of 175 (54.9%) boys’ and 144 (45.1%) girls’ were selected and subjected to a ‘dental record study’. The prevalence of dental caries was 93% (95% CI : 89,97) in primary dentition and 50.5% (95% CI : 42.2, 58.8) in permanent teeth. Mean dmft and DMFT was 6.2(SD 3.39) and 1.04(SD 1.34) respectively. Regarding treatment needs in the primary dentition, 35.4% of teeth needed one surface filling, 34.7% needed extraction, 24.5% needed two or more surfaces filling and 5.6% needed pulp care. In the permanent dentition, 54.7% required sealants and 21.9% required one surface restoration. The caries prevalence and treatment needs were high among this study population in the mixed dentition stage, particularly showing the early involvement of newly erupted permanent teeth. It appears that high caries prevalence in the primary dentition is a risk factor for caries in newly erupted permanent teeth. Oral health promotions programmes are required in the mixed dentition stage and may reduce the risk of caries in permanent dentition.

Knowledge, attitude and practice of sawmill workers towards noise-induced hearing loss in Kota Bharu,Kelantan

The purpose of this study was to determine the sawmill workers’ knowledge, attitude and practice (KAP) in relation to noise-induced hearing loss (NIHL). A cross-sectional study was conducted involving 83 workers from 3 factories in Kota Bharu, Kelantan. Questionnaires were distributed to obtain the socio-demography, knowledge, attitude and practice level in relation to noise-induced hearing loss (NIHL). The weak areas identified in the knowledge section were treatment aspects (15.5%), signs and symptoms of NIHL (20.2%) and risk factors (31%). As for attitude; the prevention aspects were the lowest (25.3%), followed by risk taking attitude (26.2%), and causes of hearing loss (42.1%). Overall, the practice was not encouraging at all. It is important to have an education program to raise workers’ awareness and to improve their attitude and practices towards noise-induced hearing loss.

Tooth wear prevalence and sample size determination: A pilot study

Tooth wear is the non-carious loss of tooth tissue, which results from three processes namely attrition, erosion and abrasion. These can occur in isolation or simultaneously. Very mild tooth wear is a physiological effect of aging. This study aims to estimate the prevalence of tooth wear among 16-year old Malay school children and determine a feasible sample size for further study. Fifty-five subjects were examined clinically, followed by the completion of self-administered questionnaires. Questionnaires consisted of socio-demographic and associated variables for tooth wear obtained from the literature. The Smith and Knight tooth wear index was used to chart tooth wear. Other oral findings were recorded using the WHO criteria. A software programme was used to determine pathological tooth wear. About equal ratio of male to female were involved. It was found that 18.2% of subjects have no tooth wear, 63.6% had very mild tooth wear, 10.9% mild tooth wear, 5.5% moderate tooth wear and 1.8 % severe tooth wear. In conclusion 18.2% of subjects were deemed to have pathological tooth wear (mild, moderate & severe). Exploration with all associated variables gave a sample size ranging from 560 – 1715. The final sample size for further study greatly depends on available time and resources.

Estimating the impact of physical distancing measures in containing COVID-19: an empirical analysis

BackgroundEpidemic modelling studies predict that physical distancing is critical in containing COVID-19. However, few empirical studies have validated this finding. Our study evaluates the effectiveness of different physical distancing measures in controlling viral transmission. MethodsWe identified three distinct physical distancing measures with varying intensity and implemented at different times--international travel controls, restrictions on mass gatherings, and lockdown-type measures--based on the Oxford COVID-19 Government Response Tracker. We also estimated the time-varying reproduction number (Rt) for 142 countries and tracked Rt temporally for two weeks following the 100th reported case in each country. We regressed Rt on the physical distancing measures and other control variables (income, population density, age structure, and temperature) and performed several robustness checks to validate our findings. FindingsComplete travel bans and all forms of lockdown-type measures have been effective in reducing average Rt over the 14 days following the 100th case. Recommended stay-at-home advisories and partial lockdowns are as effective as complete lockdowns in outbreak control. However, these measures have to be implemented early to be effective. Lockdown-type measures should be instituted two weeks before the 100th case and travel bans about a week before detection of the first case. InterpretationA combination of physical distancing measures, if implemented early, can be effective in containing COVID-19--tight border controls to limit importation of cases, encouraging physical distancing, moderately stringent measures such as working from home, and a full lockdown in the case of a probable uncontrolled outbreak. Research in contextO_ST_ABSEvidence before this studyC_ST_ABSEvidence on the impact of physical distancing measures on containing COVID-19 has primarily relied on epidemic modelling studies. As cases accumulate worldwide, it has become possible to use empirical data to validate the model-based findings. The few empirical studies that analyze global case data find that lockdowns and international travel restrictions are important, but have not explored, beyond these broad findings, the intensity and timeliness of the various measures to inform policymaking. Added value of this studyWe assessed, at a normalized stage of the epidemic curve, how the intensity and implementation timing of various physical distancing measures in 142 countries affect viral transmission, measured by the time-varying reproduction number (Rt). Other similar empirical studies treat the measures as binary variables, do not address the potential confounding effect of increased caseload on transmission, and do not use Rt as the primary metric. Implications of all the available evidenceOur results support the findings in modelling studies, and subsequent empirical studies, that physical distancing measures can limit disease spread. We found that full border control and complete lockdowns are effective, but less stringent measures such as stay-at-home recommendations and working from home are as effective. As such, the framing of lockdown measures as a binary approach may be counterproductive. Overall, these measures are only effective if they are implemented early.

SARS-CoV-2 transmission in different settings: Analysis of cases and close contacts from the Tablighi cluster in Brunei Darussalam

We report the transmission dynamics of SARS-CoV-2 across different settings from the initial COVID-19 cluster in Brunei, arisen from 19 attendees at the Malaysian Tablighi Jamaat gathering and resulted in 52 locally transmitted cases. Highest non-primary attack rates(ARs) were observed at a subsequent local religious gathering (14.8% [95%CI: 7.1,27.7]) and in the household (10.6% [95%CI: 7.3,15.1]. Household ARs of symptomatic cases were higher (14.4% [95%CI: 8.8,19.9]) than asymptomatic (4.4% [95%CI: 0.0,10.5]) or presymptomatic cases (6.1% [95%CI: 0.3,11.8]). Low ARs (<1%) were observed for workplace and social settings. Our analysis highlights that SARS-CoV-2 transmission varies depending on environmental, behavioural and host factors. We identify red flags of potential super-spreading events, namely densely populated gatherings for prolonged periods in enclosed settings, presence of individuals with recent travel history, and group behaviours such as communal eating, sleeping and sharing of personal hygiene facilities. We propose differentiated testing strategies that account for transmission risk. Article summary lineWe highlight the variability of SARS-CoV-2 transmission across different settings, identify settings at highest risk, and characterize the role of environmental, behavioural, and host factors in driving SARS-CoV-2 transmission.

Probable causes and risk factors for positive SARS-CoV-2 test in recovered patients: Evidence from Brunei Darussalam

We report findings of a national study in Brunei Darussalam indicating that one in five recovered patients subsequently test positive again for SARS-CoV-2--this risk is nearly three times higher in older patients (age 53 and above) than younger ones (below age 53). Review of clinical and epidemiological records do not support reinfection or reactivation as likely causes of the re-positive observation. Instead, prolonged but intermittent viral shedding is the most probable explanation. We discuss the implications of these findings for infection control and clinical practice.

Epidemiological investigation of the first 135 COVID-19 cases in Brunei: Implications for surveillance, control, and travel restrictions

BackgroundStudies on the early introduction of SARS-CoV-2 in a naive population have important epidemic control implications. We report findings from the epidemiological investigation of the initial 135 COVID-19 cases in Brunei and describe the impact of control measures and travel restrictions. MethodsEpidemiological and clinical information were obtained for all confirmed COVID-19 cases in Brunei, whose symptom onset was from March 9 to April 5, 2020 (covering the initial 5 weeks of the epidemic). Transmission-related measures such as reproduction number (R), incubation period, serial interval were estimated. Time-varying R was calculated to assess the effectiveness of control measures. ResultsA total of 135 cases were detected, of which 53 (39.3%) were imported. The median age was 36 years (range = 0.5 to 72). 41 (30.4%) and 13 (9.6%) were presymptomatic and asymptomatic cases respectively. The median incubation period was 5 days (IQR = 5, range = 1 to 11), and the mean serial interval was 5.39 days (sd = 4.47; 95% CI: 4.25, 6.53). R0 was between 3.88 and 5.96, and the doubling time was 1.3 days. By the 13th day of the epidemic, the Rt was under one (Rt = 0.91; 95% credible interval: 0.62, 1.32) and the epidemic was under control. ConclusionEpidemic control was achieved through a combination of public health measures, with emphasis on a test-isolate-trace approach supplemented by travel restrictions and moderate physical distancing measures but no actual lockdown. To maintain suppression, regular and ongoing testing of high-risk groups can supplement the existing surveillance program.

What do we know about SARS-CoV-2 transmission? A systematic review and meta-analysis of the secondary attack rate, serial interval, and asymptomatic infection

BackgroundCurrent SARS-CoV-2 containment measures rely on the capacity to control person-to-person viral transmission. Effective prioritization of these measures can be determined by understanding SARS-CoV-2 transmission dynamics. We conducted a systematic review and meta-analyses of three parameters: (i) secondary attack rate (SAR) in various settings, (ii) clinical onset serial interval (SI), and (iii) the proportion of asymptomatic infection. Methods and FindingsWe searched PubMed, medRxiv, and bioRxiv databases between January 1, 2020, and May 15, 2020, for articles describing SARS-CoV-2 attack rate, SI, and asymptomatic infection. Studies were included if they presented original data for estimating point estimates and 95% confidence intervals of the three parameters. Random effects models were constructed to pool SAR, mean SI, and asymptomatic proportion. Risk ratios were used to examine differences in transmission risk by setting, type of contact, and symptom status of the index case. Publication and related bias were assessed by funnel plots and Eggers meta-regression test for small-study effects. Our search strategy for SAR, SI, and asymptomatic infection identified 459, 572, and 1624 studies respectively. Of these, 20 studies met the inclusion criteria for SAR, 18 studies for SI, and 66 studies for asymptomatic infection. We estimated the pooled household SAR at 15.4% (95% CI: 12.2%, 18.7%) compared to 4.0% (95% CI: 2.8%, 5.2%) in non-household settings. We observed variation across settings; however, the small number of studies limited power to detect associations and sources of heterogeneity. SAR of symptomatic index cases is significantly higher than cases that were symptom-free at diagnosis (RR 2.55, 95% CI: 1.47, 4.45). Adults appear to be more susceptible to transmission than children (RR 1.40, 95% CI: 1.00, 1.96). The pooled mean SI is estimated at 4.87 days (95% CI: 3.98, 5.77). The pooled proportion of cases who had no symptoms at diagnosis is 25.9% (95% CI: 18.8%, 33.1%). ConclusionsBased our pooled estimates, 10 infected symptomatic persons living with 100 contacts would result in 15 additional cases in <5 days. To be effective, quarantine of contacts should occur within 3 days of symptom onset. If testing and tracing relies on symptoms, one-quarter of cases would be missed. As such, while aggressive contact tracing strategies may be appropriate early in an outbreak, as it progresses, control measures should transition to account for SAR variability across settings. Targeted strategies focusing on high-density enclosed settings may be effective without overly restricting social movement.