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Would an imperfect vaccine be useful in a flu pandemic?

first_imgApr 11, 2006 (CIDRAP News) – A mathematical modeling study suggests that a modestly effective vaccine could keep an influenza pandemic from striking more than 10% of the US population, but only if large amounts of vaccine were distributed quickly and the virus was not too highly contagious. The modeling study seems to lend some support to the US strategy of stockpiling a vaccine based on recent strains of H5N1 avian flu, which won’t precisely match an emerging pandemic strain. But the model incorporates many assumptions that may or may not prove accurate in the event of a pandemic, and experts note that very little H5N1 vaccine would be available if a pandemic occurred anytime soon. Germann TC, Kadau K, Longini IM, et al. Mitigation strategies for pandemic influenza in the United States. Proc Nat Acad Sci 2006 Apr 11;103(15):5935-40 [Abstract] Germann and two associates, Kai Kadau and Catherine A. Macken, all of Los Alamos National Laboratory, worked on the study with Ira M. Longini Jr., a biostatistician from the Fred Hutchinson Cancer Research Center and the University of Washington in Seattle. See also: “Aggressive” production and distribution of vaccine could control a pandemic with an R of less than 1.9, the model predicted. “We believe that a large stockpile of avian-based vaccine with potential pandemic influenza antigens, coupled with the capacity to rapidly make a better-matched vaccine based on human strains, would be the best strategy to mitigate pandemic influenza,” the authors write. “This effort needs to be coupled with a rapid vaccine distribution system capable of distributing at least 10 million doses per week to affected regions of the U.S.” Other experts who were asked to comment on the study had different reactions. Travel restrictions alone would accomplish little, according to the simulations. A 90% reduction in travel would slow the virus’s spread by only a few days to a few weeks, depending on transmissibility, and would not dent the ultimate size of the pandemic. Other control strategies used alone could limit a pandemic only if the virus had relatively low transmissibility (R of 1.6), the model predicted. For example, targeted use of antiviral drugs could succeed in that case, provided the supply was adequate and close contacts of patients could be quickly identified. But if R were 1.8, the nation would need a “prohibitively large” 51 million treatment courses of antivirals. Dr. Gregory Poland, a vaccine expert at the Mayo Clinic in Rochester, Minn., said the situation with the H5N1 vaccine being made for the US government points up the problems with the predictions. As was reported recently, the vaccine seems effective in about half of recipients, but it takes 12 times the dose used in seasonal flu vaccines, he noted. The study was supported by the National Institutes of Health (NIH). Its goals, the NIH said in a news release, were to determine how to slow the spread of a pandemic virus long enough to permit development and distribution of a well-matched vaccine and also how to limit the number of cases to less than 10% of the population, the percentage in an average flu season. The model projected that without any control effort and an R of 1.9, the virus would spread across the nation within 30 days of its first arrivals, that 122 million people would ultimately fall ill, and that the pandemic would peak in 85 days. With an R number of 2.4 and no control effort, as many as 151 million would get sick, according to the model. William Schaffner, MD, a hospital epidemiologist and professor in the infectious disease division at Vanderbilt University in Nashville, said he found the study reassuring, though he had not examined it closely. “The ultimate take-home line was that even a partially effective vaccine is an important part of the strategy,” he said.center_img For a highly transmissible virus (R greater than 1.9), it would take a combination of measures to limit the pandemic, the model predicted. For example, the combined use of vaccination, targeted antiviral use (3 million courses), school closures, social distancing, and travel restrictions could work at an R level as high as 2.4, the authors predict. With a moderately transmissible virus (meaning each case leads to fewer than 1.9 additional cases), “Our model suggests that the rapid production and distribution of vaccines, even if poorly matched to the circulating strains, could significantly slow disease spread and limit the number ill to less than 10% of the population, particularly if children are preferentially vaccinated,” says the report by Timothy C. Germann and colleagues. With a more contagious virus, additional measures such as school closings, travel bans, and antiviral drugs would have to be used in combination with vaccination, says the report published online last week by the Proceedings of the National Academy of Sciences. Michael T. Osterholm, PhD, MPH, a leading pandemic preparedness advocate, had a sharply different view of the study. “I think it’s based on a number of assumptions which in the real world won’t happen,” he said. “The idea that we’ll even have vaccine to consider in terms of dealing with the pandemic is at this point not likely for the vast majority of the world.” Osterholm, director of the University of Minnesota Center for Infectious Disease Research and Policy, publisher of the CIDRAP Web site, said “any number” of assumptions used in the model could be questioned. “I continue to worry that far too much credence is being put into theoretical models that lack reality testing in the likely world of a pandemic,” he said. “A moderately effective vaccine would work if you could get it into enough people,” said Poland, who directs the Mayo Vaccine Research Group and Program in Translational Immunovirology. “This current vaccine, if we used the whole world manufacturing capacity, offers enough doses for somewhere around 37.5 million people. So that’s not an answer.” He added that it may be necessary to make more than one vaccine, given the different clades (families) of H5N1 virus that have emerged. With a very limited supply of a vaccine for which two doses are recommended, the model showed it would be less helpful to vaccinate a given number of people with the two doses than to give just one dose to twice as many people. The model simulated the unfolding of pandemic flu in a US population of 281 million over 180 days. It factored in US census data about population distribution and commuting patterns and assumptions about the frequency of interpersonal contacts. It assumed that a few infected people would arrive from abroad each day at 14 airports in the United States. The researchers ran the simulations with four different reproductive (R) numbers (the number of additional people infected by each infected person), ranging from 1.6 to 2.4. He added that building up the capacity to treat the sick is important, but the main emphasis in pandemic preparedness should be on vaccination and other preventive measures. “The results [of the study] were so affirming of the general thoughts of the public health community that it’s really very reassuring, and I hope it stimulates further what I think is already a strong effort by HHS [the Department of Health and Human Services] to stimulate vaccine production and research on new ways to produce the flu vaccine and make better flu vaccines.” Poland also said no one knows how contagious the next pandemic virus will be. “My understanding is that the estimated R number for the 1918 pandemic was right around 3,” higher than the maximum of 2.4 used in the study, he said. “You wonder now if we truly have a novel subtype that’s easily transmissible, given the travel we have, if we wouldn’t have higher numbers. The average family is bigger than two people.” NIH news releasehttp://www.nigms.nih.gov/News/Results/FluModel040306last_img read more

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Barcelona lands coveted midfielder Frenkie de Jong on $85.4M deal

first_img“Everyone knows that I think Barcelona is a beautiful club, but I don’t know if I should see my career as a city trip.”What you’ve all been waiting for… pic.twitter.com/gDE1mujMLF— FC Barcelona (@FCBarcelona) January 23, 2019De Jong becomes the third major Barca signing of the transfer window following the arrivals of Jeison Murillo and Kevin-Prince Boateng on loan from Valencia and Sassuolo, respectively.Ajax center-back Matthijs de Ligt, 19, has also been linked with a switch to LaLiga’s reigning champions. Barcelona has signed Frenkie de Jong for an initial €75million (approx. $85.4 million), with the coveted Ajax midfielder set to join on a five-year deal for the start of the 2019-20 season.Previously linked with Manchester City, Real Madrid and Paris Saint-Germain, de Jong has opted for Camp Nou but will remain in the Eredivisie for the rest of the season. Barca has agreed to pay a potential €11m (approx. $12.5 million) in variables for the 21-year-old midfielder, who has helped Ajax reach the last 16 of the Champions League this term.De Jong has developed into one of the hottest talents in European football, and it is Barca that has won the race for his signature.With the arrival of Frenkie De Jong we add talent, youth and Barça style to our sporting project. We are convinced that he will be a key part of our team for years to come. Welcome, Frenkie! pic.twitter.com/9HCHmrlqvj— Josep Maria Bartomeu (@jmbartomeu) January 23, 2019″With the arrival of Frenkie de Jong we add talent, youth and Barca style to our sporting project,” wrote club president Josep Maria Bartomeu on Twitter. “We are convinced that he will be a key part of our team for years to come. Welcome, Frenkie!”Barca has a strong history of Dutch players, with icons such as Johan Cruyff and Ronald Koeman having represented the Catalan club.De Jong will also join a fellow Netherlands international at Camp Nou, with Jasper Cillessen — who also moved to Barca from Ajax — already on the club’s books.De Jong told Fox Sports recently he wanted clarity over his future, with City, Madrid and PSG all reportedly keen to snap him up.”I’m not going to make a hasty decision, but I’d like to be clear about it myself pretty quickly,” he said. “I do not know if I’ll make it known to the public.”De Jong had also hinted Barca would not necessarily be his next club when he added: “When I was in Barcelona, people thought I would join them, but that’s not the case.last_img read more

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US Open: Keys eases past Navarro to set up semi-final with Osaka

first_imgAmerican Madison Keys moved into her second consecutive US Open semi-final after beating 30th seed Carla Suarez Navarro and win 6-4 6-3 on Wednesday.Keys used her powerful serve and forehand to edge past the Spaniard in their quarter-final clash.The game was evenly matched to begin with but the momentum shifted towards Keys in the second set of the 83-minute affair as her powerful game pushed Navarro to the back foot.”I felt good today. You know, being out in front of an energetic crowd is always fun,” Keys said in an on-court interview. “I still haven’t totally processed this match.”.@madison_keys reaches the 3rd semifinal in her last 5 Major appearances as she defeats Suarez-Navarro 6-4, 6-3 under the lights!#USOpen pic.twitter.com/VOGVMyJKCpUS Open Tennis (@usopen) September 6, 2018Keys fired six aces and fended off both break opportunities during the match and told reporters that adapting Navarro’s versatile play proved critical.”She does a really good job…of holding the baseline and redirecting the ball,” Keys said.”So I knew that I was going to have to play really well but also know that she’s going to come up with some great shots and defend really well.”Suarez Navarro, whose own service game was under pressure, told reporters the 14th-seeded American had simply outplayed her.”She was returning in pressure situation every time because I don’t have a big first service,” the Spaniard said. “I think this was really important part of the game.”Also, she was really good with her serve. I mean, I cannot return like I used to.advertisement”She was more fresh than me. Faster, you know. That’s it.”Madison Keys steps to the line for a chance to serve out the match…#USOpen pic.twitter.com/SA5DKw7VvZUS Open Tennis (@usopen) September 6, 2018Keys, who lost the final last year to Sloane Stephens, now faces fellow power player Naomi Osaka of Japan in what could be a combustible semi-final on Thursday.She leads Osaka 3-0 in head to head and most recently defeated the 20th seed in straight sets in the third round at Roland Garros in June.”I think we play similarly,” Keys said of facing Osaka.”I think power, obviously a big serve. I think I probably have a little bit more spin on the ball, but I think she takes time away really well.”I don’t think we will have tons of long rallies.”(With inputs from Reuters)last_img read more

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All Stars captains announced

first_imgTouch Football Australia (TFA) is pleased to announce the captains of the All Stars teams that will play next Friday, 13 February at Cbus Stadium on the Gold Coast.   Touch Football will feature prominently in the overall event program for the first time in 2015; featuring some of Australia’s best players comprising a TFA All Stars Mixed team set to play an Indigenous All Stars Mixed team as a curtain-raiser to the Rugby League match.Australian Mixed Open captain, Kylie Hilder will captain the TFA All Stars team, while Australian representatives, Trent Touma (Mixed) and Marikki Watego (Women’s) will co-captain the Indigenous All Stars team. TFA All Star coach, Micheal Lovett said that Hilder was an easy selection based on the work they’ve done together at an Australian level over the past cycle as coach and captain of the Australian Mixed Open team respectively. “She is a very good leader of males and females and younger up-and-coming players, as well as the more experienced players,” Lovett said. “She is getting towards the twilight of her career but doesn’t leave anything to chance. She is well prepared fitness-wise, she works on always improving and sets a good on-field example like at last year’s National Touch League where she guided the young New South Wales Scorpions team to the Elite Eight Women’s title.”“She is very passionate about where she has come from in her Touch Football career and always remembers who has helped her get to where she is. She is proud of the Australian crest she wears and instils that into her fellow athletes.”Hilder says that being named captain of the All Stars team is a great honour and that she cannot wait until next week’s game. “To be part of this inaugural Touch Football All Stars game is amazing. Just to be selected to play with some of the best talent currently in the game is overwhelming but then to get named as captain and lead this talent has made me speechless,” Hilder said.“Being named as a captain of any team is one of the greatest honours any athlete can receive and for me being named as the first captain of the NRL All Stars Touch Football side means so much to me and will be something I will never ever forget and a highlight of my career.”Indigenous All Stars coach, Phil Gyemore said that Touma and Watego were ‘both proud indigenous players who have progressed through the Touch Football High Performance program and into the Open teams’. “They are both really strong chances of playing in the 2015 World Cup in Coffs Harbour and all players, not just Indigenous players, should be trying to follow in the footsteps of these young aspiring Touch Football players that would like to represent their country on home soil.​ They will be great leaders for the Indigenous All Stars team and are fully aware of the honour and what it means to lead this young but exciting Touch Football team on the Gold Coast.”Watego says she is ‘extremely excited’ to be named in the side and ‘truly humbled’ to be named co-captain. “Being fortunate enough to hold a position in this highly coveted team is something that I will never forget.  It’s such a great honour and privilege to be selected to represent the Indigenous community whilst playing the sport I love. I really hope that this initiative will inspire both young Indigenous and Non-Indigenous Touch Footy players to get involved and pursue Touch be it socially or competitively.”“To me, there is no higher honour than representing your family and your people in the wider community and I know my co-captain Trent, my team mates and I will cherish this opportunity.”“It would be great to see this game become a permanent fixture in the Touch Football and NRL calendar! I just can’t wait to go into camp next week and prepare for what should be an exciting game of Touch Footy!”Touma says that the game will be one of the biggest honours of his sporting career. “To be noticed by selectors to represent the Indigenous All Star team and also my people is one of the biggest honours in my sporting career. The day I received a phone call from I could not answer with a big yes quick enough,” Touma said.  “On top of being selected in this great team I was this week announced as captain alongside Marikki, a great talent in the game today. Being proud enough to represent my people but also captain this team will stay with me for a lifetime.” The game will be played at 3.00pm on Friday, 13 February. Stay tuned to www.touchfootball.com.au in the coming days to find out how you can watch the live stream of the game! Related LinksAll Stars Captainslast_img read more

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