The World Health Organization's (WHO) chief scientist Soumya Swaminathan said Saturday that six to eight new coronavirus vaccines could complete clinical trials and be subjected to regulatory review by the end of the year. She added that between them are vaccines that do not require needles and can be stored at room temperatures.

As pharmaceutical companies struggle to meet the global demands for the virus, the new vaccines will add to the ten vaccines that have already been proven effective within a year of declaring the pandemic, as the world needs more vaccinations, especially as the virus's continuous spread generates dangerous new symptoms.

Only 122 countries have begun to immunize people, according to data compiled by Bloomberg.

"We are very pleased with the vaccines we have," said Swaminathan.

"We can develop further," she said. “I think that by 2022, we will see improved vaccines emerge.

The current crop of experimental vaccines uses alternative technologies and delivery systems, and includes more single-shot vaccinations, vaccines that are given orally, by nasal spray, and through the skin using some kind of patch. According to Swaminathan, these can bring immunizations that are best suited to specific groups, such as pregnant women.

Studies are being conducted on more than 80 candidate vaccines, although some are still in the early stages of testing and may not be successful.

"We need to continue to support research and development for more candidate vaccines, especially since the need for continued enhanced immunization of the population remains unclear at this stage," Swaminathan said.

"So we need to be prepared for that in the future."

The WHO Strategic Advisory Group on Immunization is currently reviewing whether people infected with SARS-CoV-2 need two doses of the vaccine. Some research suggests that a natural infection activates the immune response to SARS-CoV-2, just like the first dose, making a second injection unnecessary.

Swaminathan added that giving just one dose of the vaccine to those who have recovered from COVID-19 could make more supplies available, although it could present "practical and logistical challenges in many countries" such as organizing for blood tests, which will be needed to measure antibody levels in patients before deciding on a second dose.