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− | <p | + | <p> <h2>Influenza Type A </h2></p> |
<center><img src="https://static.igem.org/mediawiki/2017/f/f6/Cuhk17_influenzaA2.png" width="40%" height="auto;"></center> | <center><img src="https://static.igem.org/mediawiki/2017/f/f6/Cuhk17_influenzaA2.png" width="40%" height="auto;"></center> | ||
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</p> | </p> | ||
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− | <p | + | <p><h2>Avian influenza </h2></p> |
<p style="font-family: roboto;font-size:115%;"> | <p style="font-family: roboto;font-size:115%;"> | ||
In this project, we aim to construct a set of artificial RNA biosensors to detect different influenza A viral genes, including the hemagglutinin and neuraminidase genes. We consulted local medical expert (link) and found that there is an urgent need for fast and on-site subtyping method for Avian influenza compared with other subtypes in Hong Kong. | In this project, we aim to construct a set of artificial RNA biosensors to detect different influenza A viral genes, including the hemagglutinin and neuraminidase genes. We consulted local medical expert (link) and found that there is an urgent need for fast and on-site subtyping method for Avian influenza compared with other subtypes in Hong Kong. | ||
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− | <p | + | <p> <h2>H5N1: The notorious flu </h2></p> |
<p style="font-family: roboto;font-size:115%;"> | <p style="font-family: roboto;font-size:115%;"> | ||
H5N1 is the most notorious highly pathogenic avian influenza. The first epidemic outbreak of H5N1 in human happened in Hong Kong in 1997. The flu was then spread to the entire Asia. According to the World Health Organization, there was 859 confirmed human cases since 2003 which killed 453 people with a mortality rate of 52% (5). The disease not only create tremendous economic burden to the health care system, it also greatly impact the poultry industry. During the outbreak of H5N1 in Hong Kong, 3.5 million chicken was slaughtered. About $10 billion US dollars had lost due to H5N1 outbreak (6). Although the risk of H5N1 pandemic outbreak in human population is considered to be low recently, it is considered as endemic in poultry in six countries (Bangladesh, China, Egypt, India, Indonesia, and Vietnam) (7). </p> | H5N1 is the most notorious highly pathogenic avian influenza. The first epidemic outbreak of H5N1 in human happened in Hong Kong in 1997. The flu was then spread to the entire Asia. According to the World Health Organization, there was 859 confirmed human cases since 2003 which killed 453 people with a mortality rate of 52% (5). The disease not only create tremendous economic burden to the health care system, it also greatly impact the poultry industry. During the outbreak of H5N1 in Hong Kong, 3.5 million chicken was slaughtered. About $10 billion US dollars had lost due to H5N1 outbreak (6). Although the risk of H5N1 pandemic outbreak in human population is considered to be low recently, it is considered as endemic in poultry in six countries (Bangladesh, China, Egypt, India, Indonesia, and Vietnam) (7). </p> | ||
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− | <p | + | <p> <h2>H7N9: The next H5N1? </h2></p> |
<p style="font-family: roboto;font-size:115%;"> | <p style="font-family: roboto;font-size:115%;"> | ||
H7 virus was thought to be only circulated among avian hosts but human infection is recently reported. The first case of human infection was recorded in China in 2013 (8). According to the World Health Organization (WHO), 1533 human infection cases were reported, with a mortality rate of 39% (9). In Hong Kong, 4 confirmed human cases were reported so far. H7N9 cased economic loss of about $6.5 billion in China (10). Among all the avian influenza virus, H7N9 virus was found to have the highest ability to infect humans and circulate in birds (11). WHO warned that the human infections are unusual and need to be carefully monitored. According to the Centers for Disease Control and Prevention (CDC) of the United States (12), H7N9 is the subtype that has the greatest potential to cause a pandemic in recent year compared with other subtypes. It is worried that H7N9 may cause next pandemic since the virus is evolving mechanism for human- to- human transmission (13). </p> | H7 virus was thought to be only circulated among avian hosts but human infection is recently reported. The first case of human infection was recorded in China in 2013 (8). According to the World Health Organization (WHO), 1533 human infection cases were reported, with a mortality rate of 39% (9). In Hong Kong, 4 confirmed human cases were reported so far. H7N9 cased economic loss of about $6.5 billion in China (10). Among all the avian influenza virus, H7N9 virus was found to have the highest ability to infect humans and circulate in birds (11). WHO warned that the human infections are unusual and need to be carefully monitored. According to the Centers for Disease Control and Prevention (CDC) of the United States (12), H7N9 is the subtype that has the greatest potential to cause a pandemic in recent year compared with other subtypes. It is worried that H7N9 may cause next pandemic since the virus is evolving mechanism for human- to- human transmission (13). </p> | ||
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− | <p>< | + | <p><h2>The need for new subtyping method </h2></p> |
<p style="font-family: roboto;font-size:115%;"> | <p style="font-family: roboto;font-size:115%;"> | ||
To avoid possible epidemic and pandemic outbreak, World Health Organization (WHO) has a well-established Global Influenza Surveillance and Response System (GISRS) (3). With combined effort of more than 120 national laboratories, the potential epidemic strain of influenza A virus will be selected to make vaccine to prevent possible outbreak (3). To effectively monitor the spread of avian influenza, a simple and rapid on- site method is needed for detecting the virus in both human and poultry. However, nowadays on-site diagnostic method, such as Rapid Influenza Diagnostic Tests (RIDTs), can only identify the influenza A virus but cannot subtype it (14). Traditional influenza A subtyping method rely on qRT-PCR (15). Although the technique is highly sensitive and specific (16) , it is not suitable to be relied on during the spread of disease, since it requires long time, and cannot perform in poor condition where expensive equipment and technical expertise are not available. Failure of immediate respond to the spread of disease may result in pandemic (17). Meanwhile, a novel type of riboswitch, namely toehold switch, shows its potential in detecting viral RNA on- site with short detection time and low production cost. | To avoid possible epidemic and pandemic outbreak, World Health Organization (WHO) has a well-established Global Influenza Surveillance and Response System (GISRS) (3). With combined effort of more than 120 national laboratories, the potential epidemic strain of influenza A virus will be selected to make vaccine to prevent possible outbreak (3). To effectively monitor the spread of avian influenza, a simple and rapid on- site method is needed for detecting the virus in both human and poultry. However, nowadays on-site diagnostic method, such as Rapid Influenza Diagnostic Tests (RIDTs), can only identify the influenza A virus but cannot subtype it (14). Traditional influenza A subtyping method rely on qRT-PCR (15). Although the technique is highly sensitive and specific (16) , it is not suitable to be relied on during the spread of disease, since it requires long time, and cannot perform in poor condition where expensive equipment and technical expertise are not available. Failure of immediate respond to the spread of disease may result in pandemic (17). Meanwhile, a novel type of riboswitch, namely toehold switch, shows its potential in detecting viral RNA on- site with short detection time and low production cost. | ||
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− | <p>< | + | <p><h2>Cell free system </h2></p> |
<center><img src="https://static.igem.org/mediawiki/2017/9/9c/Cellfreesystem2.png" width="50%" height="auto" ;"></center> | <center><img src="https://static.igem.org/mediawiki/2017/9/9c/Cellfreesystem2.png" width="50%" height="auto" ;"></center> | ||
Cell free system is a mixture of cytoplasmic and nuclear components from E. coli for in vitro transcription and translation (Sitaraman, 2004). Recent studies revealed that cell free system can be stored in room temperature after freeze drying (Pardee et al., | Cell free system is a mixture of cytoplasmic and nuclear components from E. coli for in vitro transcription and translation (Sitaraman, 2004). Recent studies revealed that cell free system can be stored in room temperature after freeze drying (Pardee et al., | ||
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− | <p>< | + | <p><h2>Reference: </h2></p> |
<ol> | <ol> | ||
<li>Global Influenza Programme [Internet]. World Health Organization. 2017 [cited 31 May 2017]. Available from: http://www.who.int/influenza/en/ | <li>Global Influenza Programme [Internet]. World Health Organization. 2017 [cited 31 May 2017]. Available from: http://www.who.int/influenza/en/ |
Revision as of 16:17, 24 October 2017