The U.N. health chief declared Friday that positive results from coronavirus vaccine trials mean the world “can begin to dream about the end of the pandemic,” but he said rich and powerful nations must not trample the poor and marginalized “in the stampede for vaccines.”

In an address to the U.N. General Assembly’s first high-level session on the pandemic, World Health Organization Director-General Tedros Adhanom Ghebreyesus cautioned that while the virus can be stopped, “the path ahead remains treacherous.”

The pandemic has shown humanity at “its best and worst,” he said, pointing to “inspiring acts of compassion and self-sacrifice, breathtaking feats of science and innovation, and heartwarming demonstrations of solidarity, but also disturbing signs of self-interest, blame-shifting and divisions.”

FILE - In this Feb. 12, 2020, file photo, Tedros Adhanom Ghebreyesus, Director General of the World Health Organization (WHO), gives a statement to the media about the response to the COVID-19 virus outbreak, at the World Health Organization (WHO) headquarters in Geneva, Switzerland. An email obtained by The Associated Press shows that the World Health Organization has recorded 65 cases of the coronavirus among staff based at its headquarters. (Salvatore Di NolfiKeystone via AP, File)

FILE - In this Feb. 12, 2020, file photo, Tedros Adhanom Ghebreyesus, Director General of the World Health Organization (WHO), gives a statement to the media about the response to the COVID-19 virus outbreak, at the World Health Organization (WHO) headquarters in Geneva, Switzerland. An email obtained by The Associated Press shows that the World Health Organization has recorded 65 cases of the coronavirus among staff based at its headquarters. (Salvatore Di NolfiKeystone via AP, File)

Referring to the current upsurge in infections and deaths, Tedros said without naming any countries that “where science is drowned out by conspiracy theories, where solidarity is undermined by division, where sacrifice is substituted with self interest, the virus thrives, the virus spreads.”

He warned in a virtual address to the high-level meeting that a vaccine “will not address the vulnerabilities that lie at its root” -- poverty, hunger, inequality and climate change, which he said must be tackled once the pandemic ends.

“We cannot and we must not go back to the same exploitative patterns of production and consumption, the same disregard for the planet that sustains all life, the same cycle of panic and meddling and the same divisive politics that fueled this pandemic,” he said.

FILE - In this Thursday, June 25, 2020 file photo, Tedros Adhanom Ghebreyesus, Director General of the World Health Organization (WHO), attends a press conference, at the (WHO) headquarters in Geneva, Switzerland. Ethiopia’s government is accusing the head of the World Health Organization, a fellow Ethiopian, of lobbying neighboring countries to come to the aid of the country’s rebellious Tigray regional government with arms and other support. Ethiopia’s army chief asserts to reporters that Tedros Adhanom Ghebreyesus had urged unnamed neighbors to “oppose the war and for (the Tigray People’s Liberation Front) to get arms.” (Salvatore Di NolfiKeystone via AP, File)

FILE - In this Thursday, June 25, 2020 file photo, Tedros Adhanom Ghebreyesus, Director General of the World Health Organization (WHO), attends a press conference, at the (WHO) headquarters in Geneva, Switzerland. Ethiopia’s government is accusing the head of the World Health Organization, a fellow Ethiopian, of lobbying neighboring countries to come to the aid of the country’s rebellious Tigray regional government with arms and other support. Ethiopia’s army chief asserts to reporters that Tedros Adhanom Ghebreyesus had urged unnamed neighbors to “oppose the war and for (the Tigray People’s Liberation Front) to get arms.” (Salvatore Di NolfiKeystone via AP, File)

On vaccines, Tedros said, “the light at the end of the tunnel is growing steadily brighter,” but vaccines “must be shared equally as global public goods, not as private commodities that widen inequalities and become yet another reason some people are left behind.”

He said WHO’s ACT-Accelerator program to quickly develop and distribute vaccines fairly “is in danger of becoming no more than a noble gesture” without major new funding.

He said $4.3 billion is needed immediately to lay the groundwork for mass procurement and delivery of vaccines and a further $23.9 billion is required for 2021. That total, Tedros said, is less than one-half of 1 percent of the $11 trillion in stimulus packages announced so far by the Group of 20, the world’s richest countries.

U.N. Secretary-General Antonio Guterres made a similar appeal for funding for the ACT-Accelerator at Thursday’s opening of the two-day General Assembly session. U.N. spokesman Stephane Dujarric said Friday that Guterres is frustrated and would have liked see “a much much higher rate of investment by those countries who can.”

Despite years of warnings, Tedros said, many countries were unprepared for the pandemic and assumed their health systems would protect their people. Many countries that have done best dealing with the crisis had experience responding to the outbreaks of SARS, MERS, HINI and other infectious diseases, he said.

WHO has been sharply criticized for not taking a stronger and more vocal role in handling the pandemic.

Tedros told the meeting that “clearly, the global system for preparedness needs attention.”

He said a WHO commission established in September is reviewing international health regulations. WHO is also working with several countries on developing a pilot program in which countries agree to regular and transparent reviews of their health preparedness, he said.

The pandemic also showed the need for a global system to share samples of viruses and other pathogens that cause disease to facilitate development of “medical counter-measures as global public goods” he said, welcoming Switzerland’s offer to use a high-security laboratory to manage a new biobank.

Tedros also backed European Union chief Charles Michel’s proposal for an international treaty under which WHO would monitor the risks of emerging infectious diseases in animals for transmission to humans, ensure alerts of health risks, improve access to health care, and address financing needs. He said this would provide “the political underpinning” for strengthening the global health sector.

The world spends $7.5 trillion on health every year, almost 10% of global GDP, Tedros said, but most of that money is spent in rich countries on treating disease rather than on “promoting and protecting health.”

“We need a radical rethink on the way we view and value health,” he said.

“If the world is to avoid another crisis on this scale,” Tedros said, “investments in basic public health functions, especially primary health care, are essential, and all roads should lead to universal health coverage with a strong foundation of primary health care.”