This is not a post that is related to my research but I will share what I can understand clearly from the talk. It begins with an introductory speech on "genetic variation key to survivor" by MGRC founder, Dr. Robert Hercus. It’s interesting as I was not aware of the fact that viruses such as HIV has millions of variants. There are more than 4 types of dengue viruses. A virus genome is about 10kb, so it’s fairly easy to sequence thousands of variants per day. Before getting to the eminent speaker lecture by Dr. John McCauley from National Institute for Medical Research (UK), Prof. Ramlan from UPM gave us a talk on animal influenza and some insights into virology.
What are influenza virus?
According to Wikipedia, influenza viruses are RNA viruses of the family Orthomyxoviridae that cause flu in birds and mammals. The viruses can be classified according to species ABC, strains and genotypes which can be divided into claudes. The surface proteins, HA and NA subunits play important roles in infection. Therefore, most viruses are named based on these proteins: H5N1, H1N1 etc. It's important to note that the AH1N1 virus contains RNA genome instead of DNA. The genome is divided into 8 segments. The reassortment of genes is a major concern.
So is H1N1 new? The answer is NO. The Spanish flu 1918 originated from a subtype of H1N1. The common types of swine flu found in pigs are H1N1, H1N2 and H3n2. There are about 1.5 million pigs in Malaysia. Based on a survey carried out by Prof. Ramlan and his team, classic influenza virus are detected in some of the 800 samples tested. The common detection method used is RT-Elisa-PCR while researchers all over the world use Real-time PCR to confirm the presence of AH1N1 virus accurately.
"A phylogenetic estimate of the gaps in genetic surveillance indicates a long period of unsampled ancestry before the S-OIV outbreak, suggesting that the reassortment of swine lineages may have occurred years before human emergence." -Smith et al. 2009, Nature.
According to
this paper published in Nature, the new virus is the combination of several other influenza viruses. Based on the phylogeny study of the proteins, it's closely related to Hong Kong H1N1 virus. It's interesting to see that bioinformatics play such a big role in this discovery.
Why did the new virus go undetected for years?
Dr. John McCauley explained that this is due to the lack of swine flu prevention measures taken by all the countries. The flu symptoms are mild i.e. lose weight and abortion.
When will the vaccine be available? Autumn. Exact date? Unknown.
Why is the vacinne taking so long? It definitely is taking faster than any other vaccine production. Bear in mind that it's a long process. The right virus strains must be first identified. The virus is incubated in the egg. Optimization is crucial to ensure large-scale production. Clinical trial and quality control must be carried out. Lastly, it involves licensing and other legal actions to make it available in the market.
What lessons can we learn?
Governments have to invest heavily on influenza viruses R&D. More effective prevention measures must be taken by all the countries on the next outbreak. Faster drugs and vaccines development. It's a matter of time before the virus become resistant to Tamilflu. Nobody can tell where all this is all going. Everyone is waiting to see what happens next.
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