Experts look for clues in 1918 pandemic virus family tree

first_imgJun 29, 2009 (CIDRAP News) – To outside observers, the novel H1N1 virus spreading quickly to every corner of the globe must seem like it came out of nowhere, but the organism is a fourth generation of the 1918 pandemic virus and comes from an H1N1 family tree that is colorful and complex, according to two historical reviews that appear today in the New England Journal of Medicine (NEJM).Understanding the history of swine influenza viruses, particularly their contribution to the 1918 pandemic virus, underscores the need to better comprehend zoonotic viruses as well as the dynamics of human pandemic viruses that can arise from them, the authors report in an early online NEJM edition.The world is still in a “pandemic era” that began in 1918, wrote three experts from the National Institute of Allergy and Infectious Diseases (NIAID), senior investigator David Morens, MD, medical epidemiologist Jeffery Taubenberger, MD, PhD, and NIAID director Anthony Fauci, MD.The 1918 virus has used a “bag of evolutionary tricks” to survive in humans and pigs and to launch other novel viruses, they wrote. “The 2009 H1N1 pandemic virus represents yet another genetic product in the still-growing family tree of this remarkable 1918 virus.”The novel H1N1 virus’ complex evolutionary history involved genetic mixing within human viruses and between avian- and swine-adapted viruses, gene segment evolution in multiple species, and evolution from the selection pressure of herd immunity in populations at different times, the group wrote, adding. “The fact that this novel H1N1 influenza A virus has become a pandemic virus expands the previous definition of the term,”Though any new virus is unpredictable, Fauci and his colleagues wrote that in this pandemic era, severity appears to be decreasing over time, with an evolutionary pattern that appears to favor transmissibility over pathogenicity.Two researchers from the University of Pittsburgh, in a review article on the emergence of H1N1 viruses, wrote that viral adaptation to a new host species is complex, but the 1918 influenza A H1N1 virus was unusual because it emerged from a bird source in pigs and humans at the same time. In contrast, researchers have said the new H1N1 virus probably emerged from swine to humans. The authors are Shanta Zimmer, MD, from the medical school, and Donald Burke, MD, from the graduate school of public health.Previous research suggests that antibody specificity against the 1918 human influenza virus diverged quickly from swine influenza viruses, and genetic differences in hemagglutinin (HA) continue to show the same type of rapid divergence between human and swine viruses, they wrote.Researchers still don’t know why H1N1 retreated in 1957 for the next 20 years, though likely factors include high levels of existing homologous immunity plus the sudden appearance of heterologous immunity from a new H2N2 strain, Zimmer and Burke wrote.Cross-species transfers of swine influenza H1N1 cropped up a few times over the next two decades, and human H1N1 didn’t surface again until 1977, presumably because of a laboratory accident in the former Soviet Union. This event marked a first in interpandemic history: the cocirculation of two influenza A viruses.The authors wrote that it’s difficult to predict how well the pandemic strain will compete against the seasonal H1N1 virus. Both viruses share three gene segments with their remote 1918 descendant: nucleocapsid, nonstructural, and HA. They pointed out that studies of B-cell memory response in 1918 pandemic survivors showed that the neutralizing body against HA was specific and long-lasting.Cell-mediated immunity may also affect competition between the two viruses, the authors wrote. Though it’s not clear if cytotoxic T lymphocytes clinically protect humans, they have been shown to reduce viral shedding, even in the absence of antibodies against HA and neuraminidase.”Cytotoxic T lymphocytes that are generated by seasonal influenza viruses against conserved epitopes might provide heterotypic immune responses that could dampen transmission, even in the absence of measurable antibody protection,” Zimmer and Burke wrote.Morens DM, Taubenberger JK, Fauci AS. The persistent legacy of the 1918 influenza virus. N Engl J Med 2009 Jul 16;361(3):225-29 [Full text]Zimmer SM, Burke DS. Historical perspective—emergence of influenza A (H1N1) viruses. N Engl J Med 2009 Jul 16;361(3):279-85 [Full text]last_img read more

NTTF National Junior League Serves off in Lagos

first_imgAccording to the referee of the tournament, John Peters, the enthusiasm showed by the players would make the tournament competitive as some of the players are eager to displace the already established stars in their bid to represent Nigeria in major international tournaments.“We are so excited that we are now having quite a number of junior players coming up and this is a sign that we will have quality replacement for some of our ageing players. I am so happy that this year’s tournament will be more competitive because looking at what Taiwo Mati, who is a junior player that won the national trial for the All Africa Games, there will be chance for more players to come through,” Peters said.Peters, who is Nigeria’s longest serving umpire having officiated at the Olympic Games, Commonwealth Games and All Africa Games charged the players to be of good conduct during the tournament, while there are plans to reward good conduct.Aside the total prize money of N1m, outstanding players will also be compensated by the organizers.Already, most of the registered participants have arrived Lagos on Thursday July 11 in readiness for the kick off with all eyes on the gong.Among the top junior players expected to be the cynosure of all eyes are Oyo State-born duo of Usman Okanlawon and Sadiat Akeem, who are the current West African cadet champions.To ensure that some of the players that featured at the last African Junior Championship in Ghana give room for upcoming players, the organizers have decided to include the Youth tournament (U-21) in the grand finale with the likes of Taiwo Mati, Azeez Solanke, Jamiu Ayanwale, Abayomi Animashaun, Augustine Emmanuel as well as Tosin Oribamise competing in the one-day finale on July 21.Share this:FacebookRedditTwitterPrintPinterestEmailWhatsAppSkypeLinkedInTumblrPocketTelegram The 2019 Nigeria Table Tennis Federation (NTTF) national junior league serves off on Friday July 12 at the National Stadium in Lagos.Already, 63 boys and 32 girls drawn across the country have registered for the nine-day tournament which serves a ranking event for U-18 players in the country.The tournament is being bankrolled by WEO AllSports with technical support from NTTF and the players are expected to compete for points from the preliminaries, which will end on July 19 where the finalists will battle for cash prize and honours in the grand finale scheduled for July 21 at the Molade Okoya-Thomas Hall of Teslim Balogun Stadium.last_img read more

Men’s hockey: Michigan State’s quick start downs Wisconsin in series’ finale

first_imgIt looked like Wisconsin men’s hockey team was heading in the right direction after winning its last two games, but against Michigan State Saturday night the Badgers seemed to make a detour.After defeating the Spartans the previous night, Wisconsin (4-20-4, 2-10-2-2 Big Ten) was no match for Michigan State (13-12-2, 7-5-2-2) the second time around at the Kohl Center as the Spartans put the Badgers’ two game winning streak to a halt with a 3-0 shutout.After the game, Wisconsin head coach Mike Eaves said Michigan State simply out-worked them, and seemed determined to avenge their Friday night defeat.“They battled more than we did,” Eaves said. “Give kudos to them, they came back with a fire in their belly.”Eaves was also unhappy with the way his skill players played in the series’ second tilt, saying he was disappointed with how they responded when put under pressure by Michigan State.The Badgers had no answer for Michigan State’s Ryan Keller in the first period. Eight minutes into the game, Keller put the Spartans up one with a rebound score. About five minutes later, Keller doubled down on his goal total by making a beautiful spin move right in front of the net, and then flicking a backhand shot with his back to the goal that snuck through Wisconsin goaltender Joel Rumpel’s legs.Five minutes into the second the period, Wisconsin forward Joseph LaBate hit the crossbar. That was as close as the Badgers would come to getting on the board in the second 20 minutes. Despite having a couple power play opportunities, Wisconsin was unable to crack the Spartan defense, as the score remained 2-0 in MSU’s favor heading into the third period.Wisconsin got a pair of chances on the power play in the final period, with one almost immediately out of the gate to open the frame. But as was the case throughout the night, the Badgers failed to convert and came up empty-handed on all five opportunities.LaBate felt lack of execution in big situations was a central issue in Saturday night’s game, which was a contributing factor in the struggling power play.“We just weren’t able to capitalize on our chances we had,” LaBate said. “I don’t think we had the poise and confidence that we needed tonight.”After UW failed on its first man advantage of the third period, Michigan State’s Thomas Ebbing tacked on a third goal for the Spartans five minutes in that silenced the Kohl Center crowd and effectively put the game to rest.Wisconsin’s next chance to get back on track will come next week when they hit the road to take on Michigan in a two-game series.last_img read more