Zoonosis occurs when a disease or sickness in a non-human animal is transmitted to a human being. Approximately 61% of 1415 pathogenic infections to human beings are zoonotic. The first case of a bird-to-human transmission of infection came in China in 1996. Since its inception, the H5N1 flu strain has killed more than 600 people, most of those residing in Asia. Over those 17 years, however, there have only been a few cases of avian flu infecting human beings, perhaps the most infamous being the H1N1 pandemic which broke out in 2009-10. However, there are now reports of a new strain infecting a human being.
In May of this year, a 20 year old Taiwanese woman was hospitalized after displaying flu-like symptoms – short of breath, a high fever, and severe coughing. Upon noting the symptoms, the doctors prescribed the woman Tamiflu and other antibiotics, and then sent her on her way. After the Taiwanese Centre for Disease Control studied the results of her throat-swab, doctors had cause to sound the alarm. The woman’s sickness was identified as the H6N1 strain of avian flu, a disease which had been present in chickens on the island since the 1970’s but had yet to become zoonotic.
Due to the potential severity of the illness, Taiwanese officials began investigating the origins of the flu and whether or not it was present in people who had been in contact with the 20 year old patient. Officials could find no immediate cause as to why or how the woman obtained the virus considering she worked as a clerk in a butcher shop and had no contact with live birds. In questioning 36 of her closest contacts, doctors only discovered flu-like symptoms in 6 people, none of which were infected with the H6N1 strain.
When investigating this particular strain even closer, doctors discovered unsettling news – the virus had undergone a mutation in its haemagglutinin, a binding protein, allowing it to bind to human cells. ‘‘The question again is what would it take for these viruses to evolve into a pandemic strain?’’ questioned virologist Marion Koopmans, who works for the National Institute for Public Health and the Environment in the Netherlands.
Luckily, recent reports have been released which show progress being made toward developing effective antibodies and medicines to combat the bird flu. Swiss drug-maker Novartis and Rockville, Maryland biotech company Novavax have both conducted independent clinical trials in which they have seen successful results from vaccines engineered to actively combat the bird flu. The aim of the vaccine is to boost antibodies whose particular job would be to attack the H7 and N9 proteins which stick out from the rest of the bird virus. In the Novavax study, the vaccine produced antibodies fighting against the “H” protein at an 81% success rate and produced antibodies against the “N” protein at a 90% success rate.
While none of the avian flu strains have yet to be transmitted from human-to-human, the threat always exists. The development of these new antibodies hopefully ensures that the end of the world will not be due to avian flu, but rather the zombie apocalypse, something we all know we truly want.
Image via Wikimedia Commons
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