Dr Thaer Ahmad, an emergency medicine physician who volunteered at the Nasser Hospital in southern Gaza in January, has said that health officials in the strip believed that “days of tranquillity” were needed to deliver and administer the vaccines.

“We know that there are others [cases of polio] out there. The next question is, how do we stop this?” Dr Ahmad told Al Jazeera.

“It is with clean water. You know, we use chlorine tablets to help clean and disinfect the water. There have been no chlorine tablets that have entered Gaza since January. All of the water that people are using is contaminated. It’s not safe,” Ahmad said.

“The second part is how can we get them to vaccines if we can’t even bring in medical supplies because of restrictions?” he said.

“If the Rafah border is effectively shut down, then we are totally dependent on the Israeli military allowing humanitarian aid in,” he added.

“We know that we are in jeopardy of losing many people. Kids who will be paralysed for the rest of their lives. Elderly people who could have been saved. All of these people are at risk,” he continued.

“The WHO, the Health Ministry, all different NGOs, they are saying we need days of tranquillity so that we can at least deliver these vaccines and administer them. They want to plan to roll this out on August 31. But by the looks of it, we have no chance of a successful rollout vaccination campaign.”