The COVID-19 pandemic is "most certainly not over," the head of the World Health Organization (WHO) warned at the opening of the 75th World Health Assembly (WHA) on Sunday.

The WHA kicked off in Geneva, Switzerland, on Sunday to focus on major issues including response to the continuing COVID-19 pandemic and the Global Health for Peace Initiative.

Despite a decline in reported cases since the peak of the Omicron wave, they cannot afford to relax their efforts to end the pandemic, WHO Director-General Tedros Adhanom Ghebreyesus told officials at the opening event.

"We lower our guard at our peril," he warned.

"Declining testing and sequencing means we are blinding ourselves to the evolution of the virus," he said, noting that almost 1 billion people in lower-income countries still haven't been vaccinated.

In a weekly report on the global situation published on Thursday, the WHO said the number of new COVID-19 cases appears to have stabilized after weeks of decline since late March, while the overall number of weekly deaths dropped.

While there has been progress, with 60 percent of the world's population vaccinated, "It's not over anywhere until it's over everywhere," Tedros said.

"Reported cases are increasing in almost 70 countries in all regions, and this in a world in which testing rates have plummeted," he added.

He said reported deaths are rising in Africa, the continent with the lowest vaccination coverage, and only 57 countries – almost all of them wealthy – have vaccinated 70 percent of their people.

Call for higher vaccination coverage

While the world's vaccine supply has improved, there is "insufficient political commitment to roll out vaccines," he said, adding that there are gaps in operational capacity in some countries while others lack the funds.

"In all, we see vaccine hesitancy driven by misinformation and disinformation," Tedros said. "The pandemic will not magically disappear, but we can end it."

With more than 3.8 billion COVID-19 doses administered to date, the world continues to see a stark disparity in vaccination as lower-income countries struggle to inoculate their populations. Meanwhile, higher-income nations now give fourth or even fifth doses.

According to the WHO, only 16 percent of people in low-income countries have received a single vaccine dose – compared to 80 percent in high-income countries. Eighteen countries have less than 10 percent of their population inoculated with COVID-19 vaccines.

More actions needed to protect people

All countries should maintain COVID-19 surveillance and sequencing, and be prepared to reintroduce and adjust public health and social measures as necessary, he said. Also, countries need to restore essential health services as rapidly as possible, and work with communities to build trust.

"The pandemic is not the only crisis in our world," he said, echoing the theme of the 75th WHA – "Health for Peace, Peace for Health."

He announced that the conference agenda will also include complex humanitarian crises in Afghanistan, Ethiopia, Somalia, South Sudan, Syria, Ukraine and Yemen.

"More even than pandemics, war shakes and shatters the foundations on which previously stable societies stood. It deprives whole communities of essential health services, leaving children at risk of vaccine-preventable diseases ... Indeed, war, hunger and disease are old friends," he deplored.

The WHO has verified 373 attacks on health facilities or personnel in 14 countries and territories so far this year. The attacks have claimed the lives of 154 health workers and patients and injured 131.

"Attacks on health workers and health facilities are a breach of international humanitarian law. But they are also an assault on the right to health," said Tedros.

The seven-day WHA is expected to be one with the largest number of topics discussed and resolutions passed, including the appointment of a new WHO director-general for the next five years. The incumbent chief Tedros is currently the only candidate.

(With input from agencies)