More than 30 sick climbers have been evacuated from the foot of Mount Everest, raising fears that coronavirus may scupper a hoped-for bumper season on the world's highest mountain.

Nepal's tourism industry suffered a devastating blow last year when the pandemic prompted a complete shutdown of its summits, costing millions in lost revenue.

This year authorities have eased quarantine rules in an effort to lure back foreign adventurers and have issued climbing permits to more than 400 people, a new record.

An Everest permit alone costs USD 11,000 and climbers pay upward of USD 40,000 for an expedition.

However, the warmer weather that ushers in safer conditions for scaling Nepal's dangerous, snow-capped peaks has coincided with a deadly second wave of COVID-19 infections, with active cases in the country rising six-fold in the last two weeks.

Norwegian climber Erlend Ness spent two nights sleeping in his tent at base camp last month, unsure of what was making him ill. He told AFP "I was evacuated to Kathmandu and was tested. My result was positive for COVID-19," becoming the first climber with an Everest permit to test positive for coronavirus.

Another climber Gina Marie Han-Lee decided to abandon her expedition last week over fears the disease was spreading around the base camp. "I have taken a helicopter out of EBC (Everest base camp) back to Kathmandu after one day." She continued saying, "I had no clue what I was flying into."

Officials at a health clinic catering to the climbers say more than 30 people have been flown off the camp in recent weeks and at least two have tested positive for COVID-19 after returning to the capital Kathmandu.

However, the government has yet to confirm a single case OF covid-19 on Everest.

Nepal's tourism department chief Rudra Singh Tamang said "Some evacuated may have tested positive in Kathmandu. They did not test at the base camp, so we cannot be sure where they got infected."

Health professionals at the camp say they do not have the capacity to test for the disease. One doctor said "we have permission to only work as a clinic so we don't have tests here. We have made requests but nothing has happened yet."

Tashi Sherpa of Seven Summit Treks, the largest climbing agency at Everest said "we are taking all precautions possible to make sure that there are no infections." He continues saying "we are not visiting other tents, and even groups within the camps are not mixing."

More than 400 people in Nepal have died over the last two weeks after contracting COVID-19.

The country's health system has been overwhelmed by the sudden spike, with hospitals filling fast and relatives of patients scrambling for medicine and intensive care beds.

Evacuating ill climbers from the remote peaks poses a major logistical challenge, as reported by AFP.

An Indian climber Harshvardhan Joshi said "We are very scared, there are many rumours and we don't know what is really going on."