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Veljko Veljkovic, Biomed Protection, and Slobodan Paessler, Galveston National Laboratory, have published articles on F1000Research in which they predicted the effectivemess of the flu vaccine in 2017/2018 and 2018/2019. In this guest blog, Slobodan Paessler explains how they went about this and how accurate their predictions were.

According to estimates from the Centers for Disease Control and Prevention (CDC) up to 646,000 people worldwide die each year from seasonal influenza-related respiratory illnesses. Moreover, influenza-associated deaths in the United States ranged from a low of 12,000 (during 2011-2012) to a high of 56,000 (during 2012-2013). For this reason, flu epidemics and potential pandemics pose great challenges to public health institutions and scientists.

The most effective way to prevent influenza is through vaccination. Influenza vaccine effectiveness can vary from year to year. An important factor determining vaccine effectiveness is the similarity or “match” between the influenza viruses used in the vaccine and the viruses circulating in the community during that particular flu season. Evolution of influenza viruses between the time of vaccine selection and the beginning of the flu season, week 40 for the Northern Hemisphere, can seriously hamper vaccine effectiveness.

Vaccine effectiveness against H3N2 viruses is typically lower than vaccine effectiveness against influenza H1N1 and/or influenza B viruses. It’s not uncommon to see vaccine effectiveness of about 30 percent against H3N2 viruses. Furthermore, during the flu season 2017 in Australia, vaccine effectiveness of the seasonal flu vaccine was around 10% resulting in record-high numbers of laboratory-confirmed influenza A infections, hospitalizations and deaths.

To improve vaccine effectiveness for the flu season 2018, WHO selected the new vaccine virus A/Singapore/INFIMH-16-0019/2016 in September 2017, which is better adapted to H3N2 viruses circulating in the Southern Hemisphere. The World Health Organization (WHO) in February 2018 selected the same virus for the vaccine for the season 2018–19 in the North Hemisphere.

But comparison of Australian H3N2 viruses and viruses isolated in the USA in the flu season 2017–18, performed using a novel electronic biology tool, demonstrated significant difference between these two groups of viruses. Recently published extended analysis of the compatibility between new vaccine virus and H3N2 viruses circulating in America suggests that vaccine effectiveness for the next flu season in US could be very low. Moreover, H3N2 virus A/Hong Kong/4801/2014 in vaccine for the season 2017–2018 better fits US H3N2 viruses than new vaccine virus A/Singapore/INFIMH-16-0019/2016, suggesting possibility that vaccine effectiveness of the current vaccine could be even higher than that for the new vaccine. This is a first report of vaccine effectiveness prediction prior to flu season using computational analysis.

Using the electronic biology platform, we predicted that flu vaccine in the flu season 2017/2018 in US could work as well as in the previous season. Our prediction has been recently confirmed through laboratory reports released by CDC. Of note is that this reported vaccine effectiveness for the flu season 2017/2018 was remarkable higher – especially in children – than predicted by others.

We are expecting that this electronic biology approach will be used by other researchers for rapid and accurate analysis of different influenza A viruses and for vaccine effectiveness prediction.