As India's coronavirus catastrophe worsens, new waves of infections are fast engulfing a growing number of nations across South and Southeast Asia -- with some grappling with their worst outbreaks since the pandemic began.

The World Health Organization (WHO) said on Wednesday that India had accounted for nearly half of all global infections and a quarter of deaths reported in the past week.

But cases have also skyrocketed in countries around India, from Nepal in the north to Sri Lanka and the Maldives in the south. And it's not just India's neighbors -- further away in Southeast Asia, infections are also surging in Thailand, Cambodia and Indonesia.

"The Southeast Asia region reported over 2.7 million new cases and over 25,000 new deaths, a 19% and a 48% increase respectively compared to the previous week," the WHO said on Wednesday. "India is currently driving the vast majority of this upward trend."

The rapid resurgence of the virus has placed enormous pressure on the health systems and medical supplies of these countries. Some have called for international assistance amid the deepening crisis.

On Wednesday, the International Federation of Red Cross and Red Crescent Societies (IFRC) warned more must be done to stop the tragedy unfolding across Asia.

"We need to act now and we need to act fast to have any hope of containing this human catastrophe," Alexander Matheou, the IFRC's Asia-Pacific regional director, said in a statement. "This virus has no respect for borders and these variants are running rampant across Asia."