In this photo taken, April 16, 2019, Agiu Nyang, 1, who is sick with measles, sits on the lap of his mother Amel Makir at the hospital in Kuajok, South Sudan. (SAM MEDNICK / AP)

GENEVA - While the world focuses on accelerating vaccination campaigns against COVID-19, millions of children around the world still remain vulnerable to deadly diseases, warned a joint statement issued on Monday by the World Health Organization (WHO), the United Nations Children's Fund (UNICEF) and Gavi, the Vaccine Alliance, on the occasion of World Immunization Week, which is celebrated every year in the last week of April.

Announcing an ambitious new global strategy aiming to save over 50 million lives through vaccination, the three Geneva-based organizations called for urgent action to renew the global commitment to improve access to and uptake of vaccines.

Vaccines will help us end the COVID-19 pandemic but only if we ensure fair access for all countries, and build strong systems to deliver them. 

Tedros Adhanom Ghebreyesus, World Health Organization director-general

"Vaccines will help us end the COVID-19 pandemic but only if we ensure fair access for all countries, and build strong systems to deliver them," Dr. Tedros Adhanom Ghebreyesus, the WHO's director-general, stressed in a press release.

"If we're to avoid multiple outbreaks of life-threatening diseases like measles, yellow fever and diphtheria, we must ensure routine vaccination services are protected in every country in the world," he said.

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A new WHO survey found that 37 percent of respondent countries still report disruptions to their routine immunization services.

According to the survey, 60 of these lifesaving campaigns are currently postponed in 50 countries, putting around 228 million people -- mostly children -- at risk for diseases, such as measles, yellow fever and polio.

"Even before the pandemic, there were worrying signs that we were beginning to lose ground in the fight against preventable child illness, with 20 million children already missing out on critical vaccinations," Henrietta Fore, UNICEF executive director, was quoted in the press statement.

"The pandemic has made a bad situation worse, causing millions more children to go unimmunized. Now that vaccines are at the forefront of everyone's minds, we must sustain this energy to help every child catch up on their measles, polio and other vaccines. We have no time to waste. Lost ground means lost lives."

UNICEF said it had delivered 2.01 billion vaccine doses in 2020 compared to 2.29 billion in 2019, due to the disruptions at the onset of the COVID-19 pandemic.

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Seth Berkley, CEO of Gavi, the Vaccine Alliance, stressed that millions of children across the world are likely to miss out on basic vaccines as the pandemic threatens to unravel two decades of progress in routine immunization.

"To support the recovery from COVID-19 and to fight future pandemics, we will need to ensure routine immunization is prioritized as we also focus on reaching children who do not receive any routine vaccines, or zero-dose children," he said.

"To do this, we need to work together -- across development agencies, governments and civil society -- to ensure that no child is left behind."

New Global Strategy

That is why the three organizations and other partners launched the "Immunization Agenda 2030" with the goal of saving over 50 million lives and maximize the lifesaving impact of vaccines through stronger immunization systems.

The targets to be achieved by 2030 include achieving 90 percent coverage for essential vaccines given in childhood and adolescence and halving the number of children completely missing out on vaccines, they wrote in the statement.

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Calling for bold action from all immunization stakeholders, the three organizations said that donors and governments should increase investments in vaccine research and innovation, development and delivery.

They also urged the pharmaceutical industry and scientists, working with governments and funders, to accelerate vaccine research and development (R&D) and ensure a continuous supply of affordable vaccines.

The theme of year's World Immunization Week is "Vaccines bring us closer."