Moscow - Usain Bolt leads an overwhelming majority of clean athletes, and a series of recent doping cases is not damaging athletics, the president of the ruling body IAAF, Lamine Diack, says.
Diack told dpa in an email interview ahead of Saturday's start of the world championships in Moscow that the IAAF has been a pioneer in the fight against substance abuse and will continue to take appropriate measures against offenders.
American 100 metres season leader Tyson Gay and former 100m world record holder Asafa Powell recently failed tests, and so did Powell's Jamaican compatriot sprinters Veronica Campbell-Brown and Sherone Simpson.
But Diack, an 80-year-old Senegalese who has presided over the IAAF since 1999, is not worried about the state of the sprint or the Olympic showcase sport in general.
"I do not believe that any doping issue 'severely damages' either the world championships or the sport of athletics because we are completely committed to fighting doping and have been at the forefront of the fight against doping for decades now," Diack said.
"We have a serious, committed and successful anti-doping campaign which aims to have a sport which is worthy of athletes who play by the rules. So every positive case does not damage our sport but it makes it stronger.
Diack named the fight against doping "an eternal one" and added "The absolute majority of athletes are clean - but those who aren't are news, however unrealistic a picture this gives of our sport."
He said "the men's 100m has always had a powerful hold on the public and media and that means that the impact of a 100m sprinter testing positive is always more dramatic but it is not correct to single out any particular event."
The Jamaican superstar Bolt has redefined the sprint with world records and so far 11 gold medals from worlds and Olympics, and Diack insisted that it wrong to make him, and other fast men, suspects just because of their times.
"Usain Bolt is clean - most sprinters who run under 10 seconds are clean," Diack said.
Doping has also made headlines in other parts of the world, such as in Turkey championship hosts Russia, where several athletes including Olympic discus silver medallist Daria Pishchalnikova and the initial 2012 European 800m champion Yelena Arzhakova have been banned.
Diack said that Russian officials are taking the matter serious and that their athletes are among the most tested in the world because the nation has the most athletes in the IAAF testing pool.
"It is a very good sign because it shows that positives are announced even for countries that are hosting our biggest event. I think you would be right to be more worried if there were no Russian positives in athletics," Diack said.
The doping cases have not scared away sponsors, Diack said, as they see "the attractiveness, appeal and excitement" of athletics and recognise the IAAF anti-doping measures.
Diack also defended the marketing of the IAAF centred on Bolt as "a fact of life" because "the public, in all our research, loves the sprints."
Diack will preside over the IAAF congress Wednesday and Thursday in Moscow before his term ends in 2015 when a new president will be elected by the congress ahead of the world championships in Beijing.
Frontrunners are IAAF vice-presidents Sebastian Coe, a two-times 1 500m Olympic champion and organiser of the London 2012 Olympics, and Sergey Bubka, a six-times pole vault world champion and world record holder who aims to become president of the International Olympic Commmittee in September.
"Sebastian organised an excellent edition of the Olympic Games in London, and Sergey Bubka is currently in the race to become IOC President with an election later this year. I am not ready yet to announce who I believe should be my successor as president," Diack said.
Diack expressed confidence in local organisers at the August 10-18 championships as far as security goes in the wake of the Boston Marathon bombings.
"We have received reassurances from the highest levels in Russia that the security plan in place for our event has been reviewed and will be of the highest level possible, without spoiling the atmosphere of what we hope will be a wonderful sporting event," he said.
The Moscow worlds have seen record entries with 1 974 athletes from 206 countries, which according to Diack shows the unbroken appeal of athletics.
"I am delighted that our sport continues to develop and grow in every corner of the world. This reflects well on all our members and the work they do to discover talented athletes and to bring them to world class standard," Diack said.