The global death toll from Covid-19 has topped five million, according to Johns Hopkins University.

The grim figure comes less than two years into a crisis that has not only devastated poor countries but also humbled wealthy ones with first-rate healthcare systems.

Together, the US, the European Union, UK and Brazil – all upper-middle- or high-income countries – account for one-eighth of the world’s population, but nearly half of all reported deaths.

The US alone has recorded more than 745,000 lives lost, the highest of any other nation.

Dr Albert Ko, an infectious disease specialist at the Yale School of Public Health, said: “This is a defining moment in our lifetime.

“What do we have to do to protect ourselves so we don’t get to another five million?”

The death toll, as tallied by Johns Hopkins University in the US, is about equal to the populations of Los Angeles and San Francisco combined.

It rivals the number of people killed in battles among nations since 1950, according to estimates from the Peace Research Institute Oslo.

Globally, Covid-19 is now the third leading cause of death, after heart disease and stroke.

The staggering figure is almost certainly an undercount because of limited testing and people dying at home without medical attention, especially in poor parts of the world.

Coronavirus hot spots have shifted over the 22 months since the outbreak began, turning different places on the world map red.

Now, the virus is pummelling Russia, Ukraine and other parts of Eastern Europe, especially where rumours, misinformation and distrust in government have hobbled vaccination efforts.

In Ukraine, only 17% of the adult population is fully vaccinated; in Armenia, only 7%.

Dr Wafaa El-Sadr, director of Icap, a global health centre at Columbia University, said: “What’s uniquely different about this pandemic is it hit hardest the high-resource countries. That’s the irony of Covid-19.”

Wealthier nations with longer life expectancies have larger proportions of older people, cancer survivors and nursing home residents, all of whom are especially vulnerable to Covid-19, Dr El-Sadr noted.

Poorer countries tend to have larger shares of children, teenagers and young adults, who are less likely to fall seriously ill from the coronavirus.

India, despite its terrifying Delta variant surge that peaked in early May, now has a much lower reported daily death rate than wealthier Russia, the US or UK, though there is uncertainty around its figures.

The seeming disconnect between wealth and health is a paradox that disease experts will be pondering for years.

But the pattern that is seen on the grand scale, when nations are compared, is different when examined at closer range.

Within each wealthy country, when deaths and infections are mapped, poorer neighbourhoods are hit hardest.

In the US, for example, Covid-19 has taken an outsize toll on black and Hispanic people, who are more likely than white people to live in poverty and have less access to health care.

“When we get out our microscopes, we see that within countries, the most vulnerable have suffered most,” Dr Ko said.

Wealth has also played a role in the global vaccination drive, with rich countries accused of locking up supplies.

The US and others are already dispensing booster jabs at a time when millions across Africa have not received a single dose, though the rich countries are also shipping hundreds of millions of jabs to the rest of the world.

Africa remains the world’s least vaccinated region, with just 5% of the population of 1.3 billion people fully covered.

“This devastating milestone reminds us that we are failing much of the world,” UN secretary-general Antonio Guterres said in a written statement.

“This is a global shame.”