scholarly journals Increasing similarity in the dynamics of influenza in two adjacent subtropical Chinese cities following the relaxation of border restrictions

2014 ◽  
Vol 95 (3) ◽  
pp. 531-538 ◽  
Author(s):  
Yi Tan ◽  
Tommy Tsan-Yuk Lam ◽  
Chunli Wu ◽  
Shui-shan Lee ◽  
Cécile Viboud ◽  
...  
Keyword(s):  
Hong Kong ◽  
Southern China ◽  
Human Mobility ◽  
Influenza Viruses ◽  
Mobility Patterns ◽  
Evolutionary Patterns ◽  
Two Cities ◽  
Influenza Activity ◽  
The Difference ◽  
Influenza Seasonality

The drivers of influenza seasonality remain heavily debated, especially in tropical/subtropical regions where influenza activity can peak in winter, during the rainy season, or remain constant throughout the year. We compared the epidemiological and evolutionary patterns of seasonal influenza epidemics in Hong Kong and Shenzhen, two adjacent cities in subtropical southern China. This comparison represents a unique natural experiment, as connectivity between these two cities has increased over the past decade. We found that, whilst summer influenza epidemics in Shenzhen used to peak 1–3 months later than those in Hong Kong, the difference decreased after 2005 (P<0.0001). Phylogenetic analysis revealed that influenza isolates from Shenzhen have become genetically closer to those circulating in Hong Kong over time (P = 0.045). Furthermore, although Shenzhen isolates used to be more distant from the global putative source of influenza viruses than isolates from Hong Kong (P<0.001), this difference has narrowed (P = 0.02). Overall, our study reveals that influenza activities show remarkably distinct epidemiological and evolutionary patterns in adjacent subtropical cities and suggests that human mobility patterns can play a major role in influenza dynamics in the subtropics.

Needs Assessment for a Targeted Health Promotion Campaign

2018 ◽  
Vol 13 (3) ◽  
pp. 596-604
Author(s):  
Greta Tam
Keyword(s):  
Health Promotion ◽  
Hong Kong ◽  
Avian Influenza ◽  
Influenza Pandemic ◽  
Influenza Viruses ◽  
Double Burden ◽  
Preventive Practices ◽  
Health Promotion Campaign ◽  
Influenza Activity ◽  
The Individual

ABSTRACTSince the first human A/H7N9 infection in Hong Kong, there has been an ongoing threat of human-to-human transmission, potentially causing a pandemic. Because there is no vaccine for A/H7N9, the individual preventive measures become all the more important for reducing transmission. However, due to the ongoing threat of numerous avian influenza viruses, the public may suffer from pandemic-media-fatigue. This study was done to assess the need for a targeted A/H7N9 health promotion campaign. Steven and Gillam’s framework using epidemiological, comparative, and corporate approaches was used to assess the need for a targeted A/H7N9 health promotion campaign.Local surveillance data showed that Hong Kong faces a double burden of increasing seasonal influenza activity and threat of an avian influenza pandemic. Experts warned of potential severity and difficulties in A/H7N9 control. In contrast, surveys showed that the Hong Kong public were suffering from pandemic-media-fatigue, lacked anxiety, had misconceptions, and were not vigilant in preventive practices. This was more evident in certain demographics. Content analysis showed that health promotion materials were not targeted or tailored in countries with human A/H7N9 cases. Targeted health promotion campaigns and framing the issue to increase public and media awareness are crucial in preventing the current pandemic-media-fatigue. (Disaster Med Public Health Preparedness.2019;13:596-604)

scholarly journals The "Great Lockdown": Inactive Workers and Mortality by Covid-19

2020 ◽  
Author(s):  
Nicola Borri ◽  
Francesco Drago ◽  
Chiara Santantonio ◽  
Francesco Sobbrio
Keyword(s):  
Causal Effect ◽  
Human Mobility ◽  
Age Groups ◽  
Mobility Patterns ◽  
Economic Activities ◽  
Active Population ◽  
Point Reduction ◽  
Percentage Points ◽  
Before And After ◽  
The Difference

In response to the Covid-19 outbreak, among other previous ``non-pharmaceutical interventions'', on March 22, 2020 the Italian Government imposed an economic lockdown and ordered the closing of all non-essential economic activities. This paper estimates the causal effect of this measure on mortality by Covid-19 and on mobility patterns. The identification of the causal effect exploits the variation in the number of active workers across municipalities induced by the economic lockdown. The difference-in-difference empirical design compares outcomes in municipalities above and below the median variation in the share of active population before and after the lockdown within a province, also controlling for municipality-specific dynamics, daily-shocks at the provincial level and municipal unobserved characteristics. Our results show that the intensity of the economic lockdown is associated to a statistically significant reduction in mortality by Covid-19 and, in particular, for age groups between 40-64 and older. Back of the envelope calculations indicate that 4,793 deaths were avoided, in the 26 days between April 5 to April 30, in the 3,518 municipalities which experienced a more intense lockdown. Assuming linearity, a 1 percentage point reduction in the share of active population caused a 1.32 percentage points reduction in mortality by Covid-19. We also find that the economic lockdown, as expected, led to a reduction in human mobility. Several robustness checks corroborate our empirical findings.

scholarly journals Characterization of H9 Subtype Influenza Viruses from the Ducks of Southern China: a Candidate for the Next Influenza Pandemic in Humans?

2003 ◽  
Vol 77 (12) ◽  
pp. 6988-6994 ◽  
Author(s):  
K. S. Li ◽  
K. M. Xu ◽  
J. S. M. Peiris ◽  
L. L. M. Poon ◽  
K. Z. Yu ◽  
...  
Keyword(s):  
Hong Kong ◽  
Southern China ◽  
Influenza Pandemic ◽  
Influenza Viruses ◽  
Current View ◽  
Domestic Ducks ◽  
H5n1 Influenza ◽  
Pandemic Virus ◽  
Influenza Outbreaks

ABSTRACT A current view of the emergence of pandemic influenza viruses envisages a gene flow from the aquatic avian reservoir to humans via reassortment in pigs, the hypothetical “mixing vessel.” Understanding arising from recent H5N1 influenza outbreaks in Hong Kong since 1997 and the isolation of avian H9N2 virus from humans raises alternative options for the emergence of a new pandemic virus. Here we report that H9N2 influenza viruses established in terrestrial poultry in southern China are transmitted back to domestic ducks, in which the viruses generate multiple reassortants. These novel H9N2 viruses are double or even triple reassortants that have amino acid signatures in their hemagglutinin, indicating their potential to directly infect humans. Some of them contain gene segments that are closely related to those of A/Hong Kong/156/97 (H5N1/97, H5N1) or A/Quail/Hong Kong/G1/97 (G1-like, H9N2). More importantly, some of their internal genes are closely related to those of novel H5N1 viruses isolated during the outbreak in Hong Kong in 2001. This study reveals a two-way transmission of influenza virus between terrestrial and aquatic birds that facilitates the generation of novel reassortant H9N2 influenza viruses. Such reassortants may directly or indirectly play a role in the emergence of the next pandemic virus.

scholarly journals Establishment of Influenza A Virus (H6N1) in Minor Poultry Species in Southern China

2007 ◽  
Vol 81 (19) ◽  
pp. 10402-10412 ◽  
Author(s):  
C. L. Cheung ◽  
D. Vijaykrishna ◽  
G. J. D. Smith ◽  
X. H. Fan ◽  
J. X. Zhang ◽  
...  
Keyword(s):  
Hong Kong ◽  
Influenza A ◽  
Southern China ◽  
Influenza Viruses ◽  
Common Source ◽  
Virus Surveillance ◽  
Different Types ◽  
Live Poultry ◽  
Further Development

ABSTRACT An H6N1 virus, A/teal/Hong Kong/W312/97 (W312), was isolated during the “bird flu” incident in Hong Kong in 1997. Genetic analysis suggested that this virus might be the progenitor of the A/Hong Kong/156/97 (HK/97) H5N1 virus, as seven of eight gene segments of those viruses had a common source. Continuing surveillance in Hong Kong showed that a W312-like virus was prevalent in quail and pheasants in 1999; however, the further development of H6N1 viruses has not been investigated since 2001. Here we report influenza virus surveillance data collected in southern China from 2000 to 2005 that show that H6N1 viruses have become established and endemic in minor poultry species and replicate mainly in the respiratory tract. Phylogenetic analysis indicated that all H6N1 isolates had W312-like hemagglutinin and neuraminidase genes. However, reassortment of internal genes between different subtype virus lineages, including H5N1, H9N2, and other avian viruses, generated multiple novel H6N1 genotypes in different types of poultry. These novel H6N1/N2 viruses are double, triple, or even quadruple reassortants. Reassortment between a W312-like H6N1 virus and an A/quail/Hong Kong/G1/97 (HK/97)-like H9N2 virus simultaneously generated novel H6N2 subtype viruses that were persistent in poultry. Molecular analyses suggest that W312-like viruses may not be the precursors of HK/97 virus but reassortants from an HK/97-like virus and another unidentified H6 subtype virus. These results provide further evidence of the pivotal role of the live poultry market system of southern China in generating increased genetic diversity in influenza viruses in this region.

scholarly journals Analysis of potential changes in seriousness of influenza A and B viruses in Hong Kong from 2001 to 2011

2014 ◽  
Vol 143 (4) ◽  
pp. 766-771 ◽  
Author(s):  
J. Y. WONG ◽  
P. WU ◽  
E. GOLDSTEIN ◽  
E. H. Y. LAU ◽  
D. K. M. IP ◽  
...  
Keyword(s):  
Hong Kong ◽  
Influenza A ◽  
Influenza Viruses ◽  
Regression Coefficients ◽  
Virus Infections ◽  
Time Series Regression ◽  
Respiratory Mortality ◽  
Influenza A H1n1 ◽  
Influenza Activity ◽  
Ongoing Monitoring

SUMMARYContinued monitoring of the seriousness of influenza viruses is a public health priority. We applied time-series regression models to data on cardio-respiratory mortality rates in Hong Kong from 2001 to 2011. We used surveillance data on outpatient consultations for influenza-like illness, and laboratory detections of influenza types/subtypes to construct proxy measures of influenza activity. In the model we allowed the regression coefficients for influenza to drift over time, and adjusted for temperature and humidity. The regression coefficient for influenza A(H3N2) increased significantly in 2005. The regression coefficients for influenza A(H1N1) and B were relatively stable over the period. Our model suggested an increase in seriousness of A(H3N2) in 2005, the year after the appearance of the A/Fujian/411/2002(H3N2)-like virus when the drifted A/California/7/2004(H3N2)-like virus appeared. Ongoing monitoring of mortality and influenza activity could permit identification of future changes in seriousness of influenza virus infections.

scholarly journals Infection of a child in Hong Kong by an influenza A H3N2 virus closely related to viruses circulating in European pigs

2001 ◽  
Vol 82 (6) ◽  
pp. 1397-1406 ◽  
Author(s):  
V. Gregory ◽  
W. Lim ◽  
K. Cameron ◽  
M. Bennett ◽  
S. Marozin ◽  
...  
Keyword(s):  
Influenza Virus ◽  
Hong Kong ◽  
Influenza A ◽  
Southern China ◽  
Influenza Viruses ◽  
H3n2 Virus ◽  
Human Influenza ◽  
Genetic Characteristics ◽  
Source Of Infection ◽  
Human Viruses

Influenza virus A/Hong Kong/1774/99, isolated from a young child with mild influenza, was shown to be similar in its antigenic and genetic characteristics to H3N2 viruses circulating in pigs in Europe during the 1990s and in particular to be closely related to viruses isolated from two children in the Netherlands in 1993. Similar viruses had previously not been identified outside Europe. Although there is little evidence as to how the child contracted the infection, it appears likely that pigs in southern China were the source of infection. Characteristics shared with the European swine viruses include resistance to the anti-influenza drugs amantadine and rimantadine. Thus not only does this incident once again highlight the potential of pigs as a source of novel human influenza viruses, but also indicates the potential for emergence of amantadine-resistant human viruses.

scholarly journals Characterization of H5N1 Influenza Viruses That Continue To Circulate in Geese in Southeastern China

2002 ◽  
Vol 76 (1) ◽  
pp. 118-126 ◽  
Author(s):  
Robert G. Webster ◽  
Yi Guan ◽  
Malik Peiris ◽  
David Walker ◽  
Scott Krauss ◽  
...  
Keyword(s):  
Hong Kong ◽  
Southern China ◽  
Influenza Viruses ◽  
H5n1 Influenza ◽  
Oral Inoculation ◽  
Live Poultry ◽  
High Doses ◽  
High Virus ◽  
High Degree

ABSTRACT The H5N1 influenza virus, which killed humans and poultry in 1997, was a reassortant that possibly arose in one type of domestic poultry present in the live-poultry markets of Hong Kong. Given that all the precursors of H5N1/97 are still circulating in poultry in southern China, the reassortment event that generated H5N1 could be repeated. Because A/goose/Guangdong/1/96-like (H5N1; Go/Gd) viruses are the proposed donors of the hemagglutinin gene of the H5N1 virus, we investigated the continued circulation, host range, and transmissibility of Go/Gd-like viruses in poultry. The Go/Gd-like viruses caused weight loss and death in some mice inoculated with high virus doses. Transmission of Go/Gd-like H5N1 viruses to geese by contact with infected geese resulted in infection of all birds but limited signs of overt disease. In contrast, oral inoculation with high doses of Go/Gd-like viruses resulted in the deaths of up to 50% of infected geese. Transmission from infected geese to chickens occurred only by fecal contact, whereas transmission to quail occurred by either aerosol or fecal spread. This difference is probably explained by the higher susceptibility of quail to Go/Gd-like virus. The high degree of susceptibility of quail to Go/Gd (H5N1)-like viruses and the continued circulation of H6N1 and H9N2 viruses in quail support the hypothesis that quail were the host of origin of the H5N1/97 virus. The ease of transmission of Go/Gd (H5N1)-like viruses to land-based birds, especially quail, supports the wisdom of separating aquatic and land-based poultry in the markets in Hong Kong and the need for continued surveillance in the field and live-bird markets in which different types of poultry are in contact with one another.

scholarly journals Public Transport GPS Probe and Rail Gate Data for Assessing the Pattern of Human Mobility in the Bangkok Metropolitan Region, Thailand

2021 ◽  
Vol 13 (4) ◽  
pp. 2178
Author(s):  
Songkorn Siangsuebchart ◽  
Sarawut Ninsawat ◽  
Apichon Witayangkurn ◽  
Surachet Pravinvongvuth
Keyword(s):  
Performance Assessment ◽  
Public Transport ◽  
Human Mobility ◽  
Open Data ◽  
Capital City ◽  
Metropolitan Region ◽  
Traffic Information ◽  
Mobility Patterns ◽  
Transport Planning ◽  
Java Program

Bangkok, the capital city of Thailand, is one of the most developed and expansive cities. Due to the ongoing development and expansion of Bangkok, urbanization has continued to expand into adjacent provinces, creating the Bangkok Metropolitan Region (BMR). Continuous monitoring of human mobility in BMR aids in public transport planning and design, and efficient performance assessment. The purpose of this study is to design and develop a process to derive human mobility patterns from the real movement of people who use both fixed-route and non-fixed-route public transport modes, including taxis, vans, and electric rail. Taxi GPS open data were collected by the Intelligent Traffic Information Center Foundation (iTIC) from all GPS-equipped taxis of one operator in BMR. GPS probe data of all operating GPS-equipped vans were collected by the Ministry of Transport’s Department of Land Transport for daily speed and driving behavior monitoring. Finally, the ridership data of all electric rail lines were collected from smartcards by the Automated Fare Collection (AFC). None of the previous works on human mobility extraction from multi-sourced big data have used van data; therefore, it is a challenge to use this data with other sources in the study of human mobility. Each public transport mode has traveling characteristics unique to its passengers and, therefore, specific analytical tools. Firstly, the taxi trip extraction process was developed using Hadoop Hive to process a large quantity of data spanning a one-month period to derive the origin and destination (OD) of each trip. Secondly, for van data, a Java program was used to construct the ODs of van trips. Thirdly, another Java program was used to create the ODs of the electric rail lines. All OD locations of these three modes were aggregated into transportation analysis zones (TAZ). The major taxi trip destinations were found to be international airports and provincial bus terminals. The significant trip destinations of vans were provincial bus terminals in Bangkok, electric rail stations, and the industrial estates in other provinces of BMR. In contrast, electric rail destinations were electric rail line interchange stations, the central business district (CBD), and commercial office areas. Therefore, these significant destinations of taxis and vans should be considered in electric rail planning to reduce the air pollution from gasoline vehicles (taxis and vans). Using the designed procedures, the up-to-date dataset of public transport can be processed to derive a time series of human mobility as an input into continuous and sustainable public transport planning and performance assessment. Based on the results of the study, the procedures can benefit other cities in Thailand and other countries.

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