The H7N9 strain of the recent bird flu virus outbreak in China is an entirely new phenomenon. Just like other bird flu incidents in the past, it has appeared for the first time in humans and poses a considerable global health threat to the human population. Scientists and researchers all over the world are currently trying to act fast to determine a way to stop this from potentially spreading, although no human-to-human cases have been reported yet.
The H7N9 virus is a type of the bird flu virus (also known as avian influenza virus). Since it was reported, more than 131 victims have been identified, and sadly 36 deaths have been documented as of May 16, 2013. Most cases were as a result of people being in contact with poultry, although the latest research shows that there is a possibility that this might spread between humans since it has been shown to spread between ferrets in direct contact with each other.¹
The H7N9 strain of the bird flu virus has been reported to cause a range of conditions from conjunctivitis (an influenza-related condition that is not complicated) and upper respiratory tract disease all the way to multi-organ failure and pneumonia (extremely complicated conditions).²
The first two patients reported with the disease died from refractory hypoxemia and the third patient died from septic shock.2 The three patients were hospitalized from first to last at the Shanghai Public Health Clinical Center, the Shanghai Centers for Disease and Control, and the Anhui CDC.
The H7N9 strain of the bird flu virus is an immediate concern because there is currently no vaccine available as it is completely new. Also, the strains from the patients identified with this virus were isolated and genome sequencing was performed, resulting in an analysis that showed the RNA amino acid sites were evolving and undergoing reassortment within the human population.
Although the number of cases are decreasing due to the closure of many live poultry markets in China, there is still the immediate concern of possible human-to-human contract of the disease in the case of the development of the strain into something more harmful.
The amino acid substitutions of the H7N9 strain of the bird flu virus is a global health concern because out of all the former bird flu cases, this strain has a greater potential to infect mammals due to its ability to be transformed and mutated inside the human body.
A second global health risk is that there is low detectability due to the fact that this virus has not caused severe disease in poultry.³ This limits the ability of scientists and researchers to find out if the virus is in a group of live birds, and this further increases the global threat of the virus in the future.
The third and most important global health risk is the threat of a pandemic, which is an epidemic that is geographically wide-spread, occurring throughout a region and possibly throughout the entire world.
1. Brown E. H7N9 Bird Flu can pass Between Mammals, Researchers Find [Internet]. Los Angeles Times; 2013 May 23. Available from: http://www.latimes.com/news/science/sciencenow/la-sci-sn-bird-flu-h7n9-research-ferrets-webby-20130523,0,1212299.story
2. Rongbao Gao, Bin Cao, Yunwen Hu, et al. Human Infection with a Novel Avian-Origin Influenza A (H7N9 Virus). The New England Journal of Medicine. 2013 May 16. Available from: http://www.ncbi.nlm.nih.gov/books/NBK7281/
3. WHO Risk Assessment. Human Infections with Avian Influenza A(H7N9 Virus). 2013 May 10. Available from: http://www.who.int/influenza/human_animal_interface/influenza_h7n9/RiskAssessment_H7N9_10May13.pdf