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1.
BMC Infect Dis ; 22(1): 296, 2022 Mar 28.
Article in English | MEDLINE | ID: covidwho-1765439

ABSTRACT

BACKGROUND: The global pandemic of coronavirus disease 2019 (COVID-19) has attracted great public health efforts across the world. Few studies, however, have described the potential impact of these measures on other important infectious diseases. METHODS: The incidence of 19 major infectious diseases in Zhejiang Province was collected from the National Notifiable Infectious Disease Surveillance System from January 2017 to October 2020. The entire epidemic control phase was divided into three stages. The government deployed the first level response from 24 January to 2 March (the most rigorous measures). When the outbreak of COVID-19 was under control, the response level changed to the second level from 3 to 23 March, and then the third level response was implemented after 24 March. We compared the epidemiological characteristics of 19 major infectious diseases during different periods of the COVID-19 epidemic and previous years. RESULTS: A total of 1,814,881 cases of 19 infectious diseases were reported in Zhejiang from January 2017 to October 2020, resulting in an incidence rate of 8088.30 cases per 1,000,000 person-years. After the non-pharmaceutical intervention, the incidence of 19 infectious diseases dropped by 70.84%, from 9436.32 cases per 1,000,000 person-years to 2751.51 cases per 1,000,000 person-years, with the large decrease in the first response period of influenza. However, we observed that the daily incidence of severe fever with thrombocytopenia syndrome (SFTS) and leptospirosis increased slightly (from 1.11 cases per 1,000,000 person-years to 1.82 cases per 1,000,000 person-years for SFTS and 0.30 cases per 1,000,000 person-years to 1.24 cases per 1,000,000 person-years for leptospirosis). There was no significant difference in the distribution of epidemiological characteristic of most infectious diseases before and during the implementation of COVID-19 control measures. CONCLUSION: Our study summarizes the epidemiological characteristics of 19 infectious diseases and indicates that the rigorous control measures for COVID-19 are also effective for majority of infectious diseases.


Subject(s)
COVID-19 , Communicable Diseases , Epidemics , COVID-19/epidemiology , Communicable Diseases/epidemiology , Disease Outbreaks/prevention & control , Epidemics/prevention & control , Humans , Incidence
2.
Disease Surveillance ; 36(10):981-984, 2021.
Article in Chinese | CAB Abstracts | ID: covidwho-1726088

ABSTRACT

Objective: To assess the risk of public health emergencies, both the indigenous ones and the imported ones, which might occur in the mainland of China in October 2021.

3.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-324176

ABSTRACT

An outbreak of novel coronavirus (SARS-CoV-2) was identified in China in December 2019, and has spread rapidly to more than 200 countries and areas in four months. A few studies have reported that transmissibility exists during the late incubation period based on one single infection cluster caused by SARS-CoV-2. Here based on 178 SARS-CoV-2 clusters confirmed in Zhejiang Province, we analyzed the epidemic link between all 212 secondary cases with their previous cases, and found 49 secondary cases (from 26 clusters), which were 23.11% (49/212) of the total secondary cases infected from previous cases during the latter’s incubation period. The median days from the last exposure of secondary cases to the onset of previous cases was 2.0 days (IQR: 1.00~5.00 days, 90th percentile: 9.00 days) .This study has shown transmission of the SARS-CoV-2 during the incubation period and indicated that some cases might be infectious soon after they were exposed to a prior transmitter. The results highlight the importance of extending the contact group for medical observation and isolation to those in contact with the index case nine (90th percentile) or more days before the latter’s illness onset, when medical resources were sufficient.

4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-312176

ABSTRACT

Since the outbreak of COVID-19 in December 2019 in Wuhan, Zhejiang has become the province with the largest number of cases. The aim of this article is to present Zhejiang province’s experience of establishing an accurate and smart control mechanism for epidemic prevention and control and resumption of work and production using a ‘five-colour epidemic chart’. The number of confirmed cases, proportion of local cases, and occurrence of clustered outbreaks were used as evaluation indicators to calculate the county-level epidemic risk and were assigned different weight coefficients;the absence of cases for 3 and 7 consecutive days was used as the adjustment index. When the first chart was published on February 9, there were 1 very-high-risk, 12 high-risk, and 12 low-risk counties. Under the five-colour chart, Zhejiang began to adopt precise measures to prevent and control the epidemic and resume work and production. By February 24, the low-risk counties had expanded to 82, with no high-risk and very-high-risk counties. The epidemic situation in Zhejiang province has been effectively controlled. The experience of epidemic prevention and control in Zhejiang is worthy to be emulated and learned by other countries and regions

5.
Mol Cell Probes ; 60: 101771, 2021 12.
Article in English | MEDLINE | ID: covidwho-1432043

ABSTRACT

The emergence of the influenza A(H1N1)pdm09 virus with the NA-H275Y mutation, which confers oseltamivir resistance, must be monitored, especially in patients undergoing neuraminidase inhibitor treatment. In this study, we developed a reverse transcription recombinase-aided amplification assay that has high sensitivity (detection limit: 1.0 × 101 copies/µL) and specificity for detecting the oseltamivir-resistant H275Y mutation; the assay is performed within 30 min at a constant temperature of 39° Celsius using an isothermal device. This method is suitable for the clinical application of targeted testing, thereby providing technical support for precision medicine in individual drug applications for patients with severe infection or immunosuppression.


Subject(s)
Influenza A Virus, H1N1 Subtype , Influenza, Human , Drug Resistance, Viral/genetics , Humans , Influenza A Virus, H1N1 Subtype/genetics , Influenza, Human/diagnosis , Influenza, Human/drug therapy , Mutation , Mutation, Missense , Neuraminidase/genetics , Oseltamivir/pharmacology , Recombinases , Reverse Transcription
6.
JAMA Intern Med ; 181(10): 1343-1350, 2021 10 01.
Article in English | MEDLINE | ID: covidwho-1368408

ABSTRACT

Importance: Much remains unknown about the transmission dynamics of COVID-19. How the severity of the index case and timing of exposure is associated with disease in close contacts of index patients with COVID-19 and clinical presentation in those developing disease is not well elucidated. Objectives: To investigate the association between the timing of exposure and development of disease among close contacts of index patients with COVID-19 and to evaluate whether the severity of the index case is associated with clinical presentation in close contacts who develop COVID-19. Design, Setting, and Participants: This study used a large, population-based cohort of 730 individuals (index patients) who received a diagnosis of COVID-19 in Zhejiang Province, China, from January 8 to July 30, 2020, along with a contact tracing surveillance program. Field workers visited 8852 close contacts of the index patients and evaluated them for COVID-19 through August 2020. A timeline was constructed to characterize different exposure periods between index patients and their contacts. Main Outcomes and Measures: The primary outcome was the attack rate of COVID-19, defined as the total number of new COVID-19 cases diagnosed among contacts of index patients divided by the total number of exposed contacts. A secondary outcome was asymptomatic clinical presentation among infected contacts. Relative risks were calculated to investigate risk factors for COVID-19 among contacts and asymptomatic clinical presentation among infected contacts. Results: Among 8852 close contacts (4679 male contacts [52.9%]; median age, 41 years [interquartile range, 28-54 years]) of 730 index patients (374 male patients [51.2%]; median age, 46 years [interquartile range, 36-56 years]), contacts were at highest risk of COVID-19 if they were exposed between 2 days before and 3 days after the index patient's symptom onset, peaking at day 0 (adjusted relative risk [ARR], 1.3; 95% CI, 1.2-1.5). Compared with being exposed to an asymptomatic index patient, the risk of COVID-19 among contacts was higher when they were exposed to index patients with mild (ARR, 4.0; 95% CI, 1.8-9.1) and moderate (ARR, 4.3; 95% CI, 1.9-9.7) cases of COVID-19. As index case severity increased, infected contacts were less likely to be asymptomatic (exposed to patient with mild COVID-19: ARR, 0.3; 95% CI, 0.1-0.9; exposed to patient with moderate COVID-19: ARR, 0.3; 95% CI, 0.1-0.8). Conclusions and Relevance: This cohort study found that individuals with COVID-19 were most infectious a few days before and after symptom onset. Infected contacts of asymptomatic index patients were less likely to present with COVID-19 symptoms, suggesting that quantity of exposure may be associated with clinical presentation in close contacts.


Subject(s)
COVID-19/transmission , Contact Tracing , SARS-CoV-2/pathogenicity , Adult , Aged , COVID-19/diagnosis , COVID-19/epidemiology , China , Cohort Studies , Female , Humans , Male , Middle Aged , Risk Factors , Symptom Assessment , Time Factors , Young Adult
7.
Epidemics ; 36: 100483, 2021 09.
Article in English | MEDLINE | ID: covidwho-1306958

ABSTRACT

INTRODUCTION: Most countries are dependent on nonpharmaceutical public health interventions such as social distancing, contact tracing, and case isolation to mitigate COVID-19 spread until medicines or vaccines widely available. Minimal research has been performed on the independent and combined impact of each of these interventions based on empirical case data. METHODS: We obtained data from all confirmed COVID-19 cases from January 7th to February 22nd 2020 in Zhejiang Province, China, to fit an age-stratified compartmental model using human contact information before and during the outbreak. The effectiveness of social distancing, contact tracing, and case isolation was studied and compared in simulation. We also simulated a two-phase reopening scenario to assess whether various strategies combining nonpharmaceutical interventions are likely to achieve population-level control of a second-wave epidemic. RESULTS: Our study sample included 1,218 symptomatic cases with COVID-19, of which 664 had no inter-province travel history. Results suggest that 36.5 % (95 % CI, 12.8-57.1) of contacts were quarantined, and approximately five days (95 % CI, 2.2-11.0) were needed to detect and isolate a case. As contact networks would increase after societal and economic reopening, avoiding a second wave without strengthening nonpharmaceutical interventions compared to the first wave it would be exceedingly difficult. CONCLUSIONS: Continuous attention and further improvement of nonpharmaceutical interventions are needed in second-wave prevention. Specifically, contact tracing merits further attention.


Subject(s)
COVID-19 , Epidemics , Contact Tracing , Humans , Physical Distancing , SARS-CoV-2
8.
Sci Rep ; 11(1): 11317, 2021 05 31.
Article in English | MEDLINE | ID: covidwho-1249213

ABSTRACT

Since the outbreak of COVID-19 in December 2019 in Wuhan, Zhejiang has become the province with the largest number of cases. The aim of this article is to present Zhejiang province's experience of establishing an accurate and smart control mechanism for epidemic prevention and control and resumption of work and production using a 'five-colour epidemic chart'. The number of confirmed cases, proportion of local cases, and occurrence of clustered outbreaks were used as evaluation indicators to calculate the county-level epidemic risk and were assigned different weight coefficients; the absence of cases for 3 and 7 consecutive days was used as the adjustment index. When the first chart was published on February 9, there were 1 very-high-risk, 12 high-risk, and 12 low-risk counties. Under the five-colour chart, Zhejiang began to adopt precise measures to prevent and control the epidemic and resume work and production. By February 24, the low-risk counties had expanded to 82, with no high-risk and very-high-risk counties. The epidemic situation in Zhejiang province has been effectively controlled. The experience of epidemic prevention and control in Zhejiang is worthy to be emulated and learned by other countries and regions.


Subject(s)
COVID-19/epidemiology , Pandemics/prevention & control , COVID-19/prevention & control , China/epidemiology , Color , Disease Outbreaks , Epidemics , Humans , Quarantine , Risk Assessment/statistics & numerical data
10.
PeerJ ; 8: e10350, 2020.
Article in English | MEDLINE | ID: covidwho-914776

ABSTRACT

BACKGROUND: Monitoring the reproduction number (Rt ) of the disease could help determine whether there is sustained transmission in a population, but areas with similar epidemic trends could have different transmission dynamics given the risk from imported cases varied across regions. In this study, we examined the Rt of coronavirus disease 2019 (COVID-19) by taking different dynamics of imported cases into account and compared the transmissibility of COVID-19 at different intervention periods in Hangzhou and Shenzhen. METHODS: We obtained the daily aggregated counts of laboratory-confirmed imported and local cases of COVID-19 infections in Hangzhou and Shenzhen from January 1 to March 13, 2020. Daily Rt and piecewise Rt before and after Wuhan lockdown were estimated, accounting for imported cases. RESULTS: Since the epidemic of COVID-19 in Shenzhen was dominated by imported cases, Rt was around 0.1 to 0.7 before the Wuhan lockdown. After the lockdown of Wuhan and the initialization of measures in response to the outbreak, local transmission was well-controlled as indicated by a low estimated value of piecewise Rt , 0.15 (95% CI [0.09-0.21]). On the contrary, Rt obtained for Hangzhou ranged from 1.2 to 4.9 with a piecewise Rt of 2.55 (95% CI [2.13-2.97]) before the lockdown of Wuhan due to the surge in local cases. Because of the Wuhan lockdown and other outbreak response measures, Rt dropped below unity in mid-February. CONCLUSIONS: Even though Shenzhen had more cases than Hangzhou, local transmission did not sustain probably due to limited transmission from imported cases owing to the reduction in local susceptibles as residents left the city during Chunyun. The lockdown measures and local outbreak responses helped reduce the local transmissibility.

12.
JAMA Intern Med ; 180(12): 1665-1671, 2020 12 01.
Article in English | MEDLINE | ID: covidwho-738931

ABSTRACT

Importance: Evidence of whether severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), can be transmitted as an aerosol (ie, airborne) has substantial public health implications. Objective: To investigate potential transmission routes of SARS-CoV-2 infection with epidemiologic evidence from a COVID-19 outbreak. Design, Setting, and Participants: This cohort study examined a community COVID-19 outbreak in Zhejiang province. On January 19, 2020, 128 individuals took 2 buses (60 [46.9%] from bus 1 and 68 [53.1%] from bus 2) on a 100-minute round trip to attend a 150-minute worship event. The source patient was a passenger on bus 2. We compared risks of SARS-CoV-2 infection among at-risk individuals taking bus 1 (n = 60) and bus 2 (n = 67 [source patient excluded]) and among all other individuals (n = 172) attending the worship event. We also divided seats on the exposed bus into high-risk and low-risk zones according to the distance from the source patient and compared COVID-19 risks in each zone. In both buses, central air conditioners were in indoor recirculation mode. Main Outcomes and Measures: SARS-CoV-2 infection was confirmed by reverse transcription polymerase chain reaction or by viral genome sequencing results. Attack rates for SARS-CoV-2 infection were calculated for different groups, and the spatial distribution of individuals who developed infection on bus 2 was obtained. Results: Of the 128 participants, 15 (11.7%) were men, 113 (88.3%) were women, and the mean age was 58.6 years. On bus 2, 24 of the 68 individuals (35.3% [including the index patient]) received a diagnosis of COVID-19 after the event. Meanwhile, none of the 60 individuals in bus 1 were infected. Among the other 172 individuals at the worship event, 7 (4.1%) subsequently received a COVID-19 diagnosis. Individuals in bus 2 had a 34.3% (95% CI, 24.1%-46.3%) higher risk of getting COVID-19 compared with those in bus 1 and were 11.4 (95% CI, 5.1-25.4) times more likely to have COVID-19 compared with all other individuals attending the worship event. Within bus 2, individuals in high-risk zones had moderately, but nonsignificantly, higher risk for COVID-19 compared with those in the low-risk zones. The absence of a significantly increased risk in the part of the bus closer to the index case suggested that airborne spread of the virus may at least partially explain the markedly high attack rate observed. Conclusions and Relevance: In this cohort study and case investigation of a community outbreak of COVID-19 in Zhejiang province, individuals who rode a bus to a worship event with a patient with COVID-19 had a higher risk of SARS-CoV-2 infection than individuals who rode another bus to the same event. Airborne spread of SARS-CoV-2 seems likely to have contributed to the high attack rate in the exposed bus. Future efforts at prevention and control must consider the potential for airborne spread of the virus.


Subject(s)
COVID-19 , Communicable Disease Control/methods , Community-Acquired Infections , Motor Vehicles/statistics & numerical data , SARS-CoV-2 , Transportation/methods , Air Pollution , COVID-19/diagnosis , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19/transmission , China/epidemiology , Cohort Studies , Community-Acquired Infections/diagnosis , Community-Acquired Infections/epidemiology , Community-Acquired Infections/prevention & control , Community-Acquired Infections/transmission , Disease Transmission, Infectious/prevention & control , Disease Transmission, Infectious/statistics & numerical data , Female , Humans , Male , Middle Aged , Risk Assessment , SARS-CoV-2/isolation & purification , SARS-CoV-2/pathogenicity
13.
Preprint in English | medRxiv | ID: ppmedrxiv-20155150

ABSTRACT

System-wide molecular characteristics of COVID-19, especially in those patients without comorbidities, have not been fully investigated. We compared extensive molecular profiles of blood samples from 231 COVID-19 patients, ranging from asymptomatic to critically ill, importantly excluding those with any comorbidities. Amongst the major findings, asymptomatic patients were characterized by highly activated anti-virus interferon, T/natural killer (NK) cell activation, and transcriptional upregulation of inflammatory cytokine mRNAs. However, given very abundant RNA binding proteins (RBPs), these cytokine mRNAs could be effectively destabilized hence preserving normal cytokine levels. In contrast, in critically ill patients, cytokine storm due to RBPs inhibition and tryptophan metabolites accumulation contributed to T/NK cell dysfunction. A machine-learning model was constructed which accurately stratified the COVID-19 severities based on their multi-omics features. Overall, our analysis provides insights into COVID-19 pathogenesis and identifies targets for intervening in treatment.

14.
Open Forum Infect Dis ; 7(6): ofaa231, 2020 Jun.
Article in English | MEDLINE | ID: covidwho-622578

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2, the pathogen causing novel coronavirus disease of 2019 (COVID-19), efficiently spreads from person to person in close contact settings. Transmission among casual contacts in settings such as during social gatherings is not well understood. METHODS: We report several transmission events to both close and casual contacts from a cluster of 7 COVID-19 cases occurring from mid-January to early February 2020. A total of 539 social and family contacts of the index patient's, including members of a 2-day wedding and a family party, were contacted and screened through epidemiologic surveys. The clinical progression of all cases is described. RESULTS: We estimate the secondary attack rate among close contacts to be 29% (2 of 7) and for the casual contacts to be 0.6% (3 of 473). The incubation period of our case cluster was 4-12 days (median, 7 days). CONCLUSIONS: Transmission efficiency among close contacts was higher than among casual contacts; however, transmission from second-generation cases may help spread the virus during the incubation period.

16.
Int J Infect Dis ; 96: 128-130, 2020 Jul.
Article in English | MEDLINE | ID: covidwho-281360

ABSTRACT

Owing to the frequent travel connections between Wuhan and Zhejiang, Zhejiang was the third worst-affected province in China with 1,205 cases confirmed before 26 February 2020. The transmissibility of the 2019 novel coronavirus disease was monitored in Zhejiang, accounting for the transmissions from imported cases. Even though Zhejiang was one of the worst-affected provinces, an interruption of disease transmission (i.e. instantaneous reproduction numbers <1) was observed in early/mid-February after a comprehensive set of interventions combating the outbreak.


Subject(s)
Betacoronavirus , Coronavirus Infections/transmission , Pneumonia, Viral/transmission , Basic Reproduction Number , COVID-19 , China/epidemiology , Coronavirus Infections/epidemiology , Humans , Pandemics , Pneumonia, Viral/epidemiology , SARS-CoV-2
17.
Preprint in English | medRxiv | ID: ppmedrxiv-20041061

ABSTRACT

BACKGROUNDThere is little information about the coronavirus disease 2019 (Covid-19) during pregnancy. This study aimed to determine the clinical features and the maternal and neonatal outcomes of pregnant women with Covid-19. METHODSIn this retrospective analysis from five hospitals, we included pregnant women with Covid-19 from January 1 to February 20, 2020. The primary composite endpoints were admission to an intensive care unit (ICU), the use of mechanical ventilation, or death. Secondary endpoints included the clinical severity of Covid-19, neonatal mortality, admission to neonatal intensive care unit (NICU), and the incidence of acute respiratory distress syndrome (ARDS) of pregnant women and newborns. RESULTSThirty-three pregnant women with Covid-19 and 28 newborns were identified. One (3%) pregnant woman needed the use of mechanical ventilation. No pregnant women admitted to the ICU. There were no moralities among pregnant women or newborns. The percentages of pregnant women with mild, moderate, and severe symptoms were 13 (39.4%),19(57.6%), and 1(3%). One (3.6%) newborn developed ARDS and was admitted to the NICU. The rate of perinatal transmission of SARS-CoV-2 was 3.6%. CONCLUSIONSThis report suggests that pregnant women are not at increased risk for severe illness or mortality with Covid-19 compared with the general population. The SARS-CoV-2 infection during pregnancy might not be associated with as adverse obstetrical and neonatal outcomes that are seen with the severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) infection during pregnancy. (Funded by the National Key Research and Development Program.)

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