The unprecedented demand for COVID-19 vaccine manufacturing worldwide has led to a shortage of key supplies, including glass vials, plastic filters, and the raw materials needed to make them, warned the World Health Organization (WHO) on Friday.

The lack is "limiting the production of vaccines for COVID-19 and could put the supply of routine childhood vaccines at risk," said WHO Director-General Tedros Adhanom Ghebreyesus at the daily press briefing.

With the cumulative supply target of up to 14 billion doses of COVID-19 vaccines by the end of 2021, "it has become apparent that many COVID-19 vaccine input supplies of raw and packaging materials, consumables and equipment are in short supply which may result in several COVID-19 vaccines manufactures not being able to meet their current vaccine manufacturing commitments," reads a discussion paper presented at meeting on March 9 organized by UK-based think tank Chatham House, in collaboration with the International Federation of Pharmaceutical Manufacturers and Associations and other international stakeholders.

Lack of vaccine supply keeps experts 'up at night'

The supply of COVID-19 vaccines is "keeping us up at night," Richard Hatchett, chief executive of the Coalition for Epidemic Preparedness Innovations, told The Telegraph.

Glass vials are one of the products that are under significant supply challenges. Sand is the key component on glass, concrete, asphalt, and even silicon microchips, so it is considered to be the most consumed raw material after water. However, the world is now heading towards "sand shortage," according to the UN Environment Programme (UNEP).

According to a UNEP report, the world extracts over 40-billion-tons of sand every year. The global rate of sand use has "tripled over the last two decades" and "far exceeds the natural rate at which sand is being replenished by the weathering of rocks by wind and water," CNBC reported.

"We just think that sand is everywhere… We never thought we would run out of sand, but it starting in some places. It is about anticipating what can happen in the next decade or so because if we don't look forward if we don't anticipate, we will have massive problems about sand supply but also about land planning," Pascal Veluzzi, a climate scientist at UNEP told CNBC.

The other factor threatening vaccine supply is the emerging trend of governments blocking raw material exports, cautioned Hatchett.

The U.S. announced the use of the Defense Production Act to curb the export of raw materials and accelerate domestic vaccine production last month.

Adar Poonawalla, CEO of Serum Institute of India, the vaccine manufacturer that partnered with AstraZeneca and Novavax, said at a World Bank panel discussion that the U.S. decision will hamper the global vaccination efforts, Bloomberg reported.

"The Novavax vaccine, which we're a major manufacturer for, needs these items from the U.S.," Poonawalla told Bloomberg. "If we're talking about building capacity all over the world, the sharing of these critical raw materials is going to become a critical limiting factor – nobody has been able to address this so far."

Such legal restrictions on the export of critical supplies "is putting lives at risk around the world," said Tedros on Friday. "We call on all countries not to stockpile supplies that are needed urgently to ramp up production of vaccines."

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