The race is on to produce a vaccine against COVID-19 but it is not certain that one can be found, the head of the global vaccines alliance said Friday.

Seth Berkley said the more competition the better in the scientific fightback against the new coronavirus pandemic, which has killed nearly 200,000 people since it emerged in December.

The head of the Gavi Vaccine Alliance also said confidence in an eventual COVID-19 vaccine would be greatly boosted if political leaders were seen getting immunised, saying he was “quite disturbed” by highly-politicised campaigns against vaccination.