For paramedics dealing with a surge in coronavirus infections in Mexico, finding an available bed for patients in overwhelmed hospitals has become a daily lottery.

"For there to be room, one person has to be discharged or die. It's tough but it's the truth," said Angel Zuniga, a Red Cross coordinator in the city of Toluca southwest of the capital.

"One goes in and another comes out," Zuniga added.

In Mexico City and neighboring areas, 64 of 78 hospitals were in a "critical" state on Friday with beds available in only a handful of them, according to the authorities.

In the capital itself, home to nine million people, 86 percent of hospital beds were occupied.

The problem is not confined to the public sector.

Private clinics, where many coronavirus patients turn in the hope of finding a place, are also overcrowded.

Some turn away patients unless they give a deposit of 170,000 pesos (about $8,400).

"They say 'take him away' and we'll go back to the street again," looking for another hospital, Zuniga said.

- 'You become desperate' -

Even when there is room for another patient, it sometimes takes hours before they are admitted.

"It's frustrating, but if we collapse, the healthcare system will collapse too. So, we always try to stay positive," said Miguel Angel Moreno, a paramedic from Naucalpan near the capital.

"As humans, there's obviously a point at which you become desperate."

On top of the emotional stress comes the physical toll and discomfort of having to wear a protective suit for hours.

"Fatigue is always an issue," said senior paramedic Ana Yesi Hernandez.

"Sometimes it takes them three to four hours to find a spare bed in a hospital."

Mexico's official Covid-19 death toll, the fourth highest in the world, now stands at nearly 134,000, with more than 1.5 million cases registered.

The authorities acknowledge that the real figure is probably much higher due to limited testing.

On Friday authorities scrapped plans to reopen non-essential activities in the capital.

"The city is today at its highest level of hospitalization since the start of the pandemic," Mayor Claudia Sheinbaum said.

Paramedics say the patients they are seeing now probably got sick while gathering to celebrate Christmas.

Soon they expect to see those who caught the virus during the New Year holiday.

They are praying for some respite after that wave subsides.

Beyond that they are counting on the vaccination program that the government began on December 24, with priority going to health workers.

"We all have high hope for the vaccine," Zuniga said.