The diagnostic accuracy of rapid diagnostic tests for Ebola virus disease: a systematic review

BackgroundEbola virus disease (EVD) is a dangerous condition that can cause an epidemic. Several rapid diagnostic tests (RDTs) have been developed to diagnose EVD. These RDTs promise to be quicker and easier to use than the current reference standard diagnostic test, PCR.ObjectivesTo assess the diagnostic accuracy of RDTs for EVD.MethodsA systematic review of diagnostic accuracy studies.Data sourcesThe following bibliographic databases were searched from inception to present: MEDLINE (Ovid), Embase, Global Health, Cochrane Central Register of Controlled Trials, WHO Global Index Medicus database, Web of Science, PROSPERO register of Systematic Reviews, and Clinical Trials.Gov.Study eligibility criteriaDiagnostic accuracy studies.ParticipantsPatients presenting to the Ebola treatment units with symptoms of EVD.InterventionsRDTs; reference standard, RT-PCR.Assessment of risk of biasQuality Assessment of Diagnostic Accuracy Studies-2 tool.Methods of data synthesisSummary estimates of diagnostic accuracy study were produced for each device type. Subgroup analyses were performed for RDT type and specimen material. A sensitivity analysis was performed to assess the effect of trial design and bias.ResultsWe included 15 diagnostic accuracy studies. The summary estimate of sensitivity for lateral flow assays was 86.1% (95% CI, 86–86.2%), with specificity of 97% (95% CI, 96.1–97.9%). The summary estimate for rapid PCR devices was sensitivity of 96.2% (95% CI, 95.3–97.9%), with a specificity of 96.8% (95% CI, 95.3–97.9%). Pre-specified subgroup analyses demonstrated that RDTs were effective on a range of specimen material. Overall, the risk of bias throughout the included studies was low, but it was high in patient selection and uncertain in the flow and timing domains.ConclusionsRDTs possess both high sensitivity and specificity compared with RT-PCR among symptomatic patients presenting to the Ebola treatment units. Our findings support the use of RDTs as a ‘rule in’ test to expedite treatment and vaccination.     

Status of Foot‐and‐mouth Disease in India

Foot‐and‐mouth disease (FMD) is endemic in India and causes severe economic loss. Status of FMD in the country for five fiscal years is presented. Outbreaks were more in number in 2007–2008 than 2010–2011. Three serotypes of FMD virus (O, A and Asia1) are prevalent. Serotype O was responsible for 80% of the confirmed outbreaks/cases, whereas Asia1 and A caused 12% and 8%, respectively. Geographical region‐wise assessment indicated varying prevalence rate in different regions viz; 43% in Eastern region, 31.5% in Southern region, 11.6% in North‐eastern region, 5% Central region, 4.4% Western region and 4% in Northern region. Highest number of outbreaks/cases was recorded in the month of September and lowest in June. Emergence and re‐emergence of different genotypes/lineages within the serotypes were evident in real‐time investigation carried out from time to time. Continues antigenic divergence in serotype A resulted in change in the vaccine strain in 2009. As on date, all genetic diversity within the serotypes is well tolerated by the vaccine strains. Unrestricted animal movements in the country play a major role in the spread of FMD.     

Drainage systems,an occluded source of sanitation related outbreaks

Background

Drainage systems and its role in sanitation related outbreaks are evident but still occluded once it has been installed. This current review evaluates if drainage systems can cause infections and thus be of clinical concern.

Method

A review of the literature was analyzed. Papers, guidelines, and quality management systems have been considered.

Results

Adequate sanitation is fundamental and a prerequisite for safe life and productivity. In contrast, malfunctioning sanitation has been reported to cause outbreaks all over the world. In areas with no sanitation, diarrheal mortality is high and has been shown to decrease by 36% after interventions to improve sanitation. Often, infections are faeces associated and when present in wastewater and sewage sludge poses a high risk of infection upon exposure. Hence, there are working safety guidelines and in industries where infection reduction is essential strict quality assurance systems, i.e. HACCP (hazard analysis critical control points) and GMP (Good Manufacturing Practice) must be complied. Healthcare has recently taken interest in the HACCP system in their efforts to reduce healthcare associated infections as a response to increasing number of ineffective antibiotics and the threat of mortality rate like the pre-antibiotic era. The last few years have called for immediate action to contain the emergence of increasing resistant microorganisms. Resistance is obtained as a result of overuse and misuse of antibiotics in both healthcare and agriculture. Also, by the discharge of antibiotics from manufacturers, healthcare and society. One mechanism of development of novel resistant pathogens has been shown to be by effortless sharing of genetic mobile elements coding for resistance from microbes in the environment to human microbes. These pathogens have been sampled from the drainage systems. These were noticed owing to their possession of an unusual antibiotic resistance profile linking them to the outbreak. Often the cause of sanitation related outbreaks is due to inadequate sanitation and maintenance. However, in general these infections probably go unnoticed.

Conclusion

Drainage systems and its maintenance, if neglected, could pose a threat in both community and healthcare causing infections as well as emergence of multi-resistant bacteria that could cause unpredictable clinical manifestations.     

2007-2021年我国诺如病毒急性胃肠炎暴发疫情流行特征及影响因素分析

目的 分析我国诺如病毒急性胃肠炎暴发疫情流行病学特征,探讨暴发疫情规模的影响因素,为及早控制暴发疫情提供科学依据。方法 对突发公共卫生事件管理信息系统2007年1月1日至2021年12月31日全国诺如病毒急性胃肠炎暴发疫情进行描述性流行病学分析,应用非条件logistic回归模型分析暴发疫情规模的影响因素。结果 2007-2021年共报告暴发诺如病毒急性胃肠炎疫情1 725起,报告疫情起数呈上升趋势。南方省份每年10月至次年3月为疫情高峰,北方省份疫情高峰为每年10-12月和次年3-6月。疫情报告地区从东南沿海省份逐步向中部、东北和西部省份扩散。疫情主要发生在学校和托幼机构（1 539起,89.22%）,其次为企事业单位（67起,3.88%）和社区家庭（55起,3.19%）。人与人接触为主要传播途径1 262起（73.16%）,GⅡ基因型为引起暴发疫情的主要病原型别（899起,81.58%）。首例病例发病至疫情报告时间间隔M（Q₁,Q₃）为3（2,6）d,疫情规模M（Q₁,Q₃）为38（28,62）例。近年来,疫情报告及时性提升,疫情规模随年份呈下降趋势,二者在不同发生场所之间差异均有统计学意义（P<0.001）。发生场所、传播途径、报告及时性和居住地类型是暴发疫情规模的影响因素（P<0.05）。结论 2007-2021年我国诺如病毒急性胃肠炎暴发疫情整体呈上升趋势,疫情波及地区范围不断扩大,但疫情发生规模整体呈下降趋势,疫情报告及时性提升,提高监测灵敏度和及早报告可有效控制疫情发生规模。     

An insight into the mental health needs of the common public of Tamil Nadu,India, subjected to COVID-19 lockdown,a rare unprecedented crisis

PurposeCOVID-19, a major “Public Health Emergencies of International Concern”, had sought greater attention among researchers to study its pathogenesis, associated complications and management. However, there are only few studies that had studied its potential impact on mental health of general public, who are subjected to social distancing, community lockdown and restrictions in their routine activities.ObjectivesThe aim of this study is to assess the prevalence of psychological distress and mental health needs among general public in Tamil Nadu subjected to lockdown, social distancing amidst COVID-19 crisis. Tamil Nadu is one of the worst affected states of southern India.MethodsA self-administered, web-based application study using “WHO-Self Reported Questionnaire-20”, in bilingual version, both English and Tamil, is used to screen the public for the level of distress. The study is done while the state is under extended lockdown and restricted movement.Key findingsA total of 918 respondents participated in the survey and it is found that about more than one third of the respondents (～35%) are under psychological distress. A significant association between younger age group, female gender, unmarried, people with children are found to be under distress. The lockdown had increased the frequency of smoking and quantity of cigarettes among smokers, also has increased the frequency of drinking among alcohol consumers. Of the SRQ-20 items recorded, stress related neurotic symptoms (> 70%) was observed more than the depressive mood. About 33% of those scored > 7, had suicidal tendency. The districts declared red zones had significantly reported a greater number of respondents under distress.ConclusionBesides effectively mitigating the COVID-19 crisis, in terms of prevention, control and treatment strategies, it is prerogative to effectively manage fear, distress due to the COVID-19 and associated anxiety and depression among the public.     

Mumps vaccine effectiveness and risk factors for disease in households during an outbreak in New York City

Background and objectives

Mumps outbreaks have been reported among vaccinated populations, and declining mumps vaccine effectiveness (VE) has been suggested as one possible cause. During a large mumps outbreak in New York City, we assessed: (1) VE of measles-mumps-rubella vaccine (MMR) against mumps and (2) risk factors for acquiring mumps in households.

Methods

Cases of mumps were investigated using standard methods. Additional information on disease and vaccination status of household contacts was collected. Case households completed follow-up phone interviews 78–198 days after initial investigation to ascertain additional cases. Mumps cases meeting the study case definition were included in the analysis. Risk factors for mumps were assessed, and VE was calculated using secondary household attack rates.

Results

Three hundred and eleven households with 2176 residents were included in the analysis. The median age of residents was 13 years (range <1–85), and 462 (21.2%) residents met the study mumps case definition. Among 7–17 year olds, 89.7% received one or more doses of MMR vaccine, with 76.7% receiving two doses. Young adults aged 10–14 years (OR = 2.4, CI = 1.3–4.7) and 15–19 years (OR = 2.5, CI = 1.3–5.0) were at highest risk of mumps. The overall 2-dose VE for secondary contacts aged five and older was 86.3% (CI 63.3–94.9).

Conclusions

The two-dose effectiveness of MMR vaccine against mumps was 86.3%, consistent with other published mumps VE estimates. Many factors likely contributed to this outbreak. Suboptimal MMR coverage in the affected population combined with VE may not have conferred adequate immunity to prevent transmission and may have contributed to this outbreak. Achieving high MMR coverage remains the best available strategy for prevention of mumps outbreaks.     

2007年上海市某小学水痘爆发的流行病学调查

目的 通过调查上海市某小学的水痘爆发,分析水痘的传播途径和流行过程,评价水痘减毒活疫苗(Varicella Attenuated Live Vaccine,VarV)接种现状和保护率,探索水痘免疫对策.方法 2007年10月29日～2008年1月19日,对该校所有在校学生进行水痘发病问卷调查,同时查询VarV预防接种记录,分析爆发的危险因素,计算疫苗保护率.结果 1172名学生中,86.3%/4(1012/1172)在爆发前无水痘患病史,66.8%(676/1012)有VarV接种史.本次水痘发病73例,共形成3次发病高峰.病例主要分布在3～5年级,1、2年级无水痘发病,且VarV接种率较高[分别为85.3%(139/163)和76.8%(152/198)].无接种史的易感者水痘罹患率非常显著地高于有接种史者(x2=23.45,P<0.001),VarV保护率是68.5%(95%可信限为54.5%～75.5%).保护率随接种时间延长而明显下降(x2=4.131,P=0.0421).46.6%(34/73)的患者未能及时隔离,具有传播可能性.结论 低接种率、免疫时间较长和缺乏及时的报告隔离制度,是此次水痘爆发的主要危险因素.提高中、高年级小学生VarV接种率,深入评价免疫方案,改善水痘监测系统,对预防水痘爆发具有重要意义.     

Malaria epidemic and drug resistance, Djibouti

Analysis of Plasmodium falciparum isolates collected before, during, and after a 1999 malaria epidemic in Djibouti shows that, despite a high prevalence of resistance to chloroquine, the epidemic cannot be attributed to a sudden increase in drug resistance of local parasite populations.