BEIJING - Some major Chinese cities, including Beijing, will continue to be threatened by low blood reserves due to increasing demands and declining donations, according to an official with the Ministry of Health.

The pressure on blood reserves emerged near the end of last year and is becoming "permanent" in a few regions, said Guo Yanhong, vice-director of the ministry's medical administration division.

Although the amount of blood donated at the national level has increased for years, Beijing and Zhejiang province both reported declines this year, Guo said.

Official statistics show that donations in the past six months dropped 7.31 percent in the Chinese capital over the same period last year, after years of continuous growth.

The shrinkage happened partly because of the public's mistrust of the country's Red Cross branches after a series of embezzlement scandals, said Liu Jiang, director of the Beijing Red Cross Blood Center.

Liu also attributed the drop to the low temperatures in winter that could have deterred people from going to blood-collecting vans on the street, which constitute the main source of blood donations.

Despite the drop in the city's blood reserves, the number of patients queueing for surgeries continues to grow.

The annual growth of medical surgeries in 2010 was 18.6 percent, while the blood donated only grew by about 7.7 percent, Guo said.

Guo noted that the imbalance was more obvious in major cities where the best hospitals are located and attract patients from the whole country.

The ministry estimates the total quantity of blood donations stands at around 4,000 tonnes this year, while demand could reach 6,000 tonnes by 2015.

At that ratio, the ministry would need about 120,000 people to donate every day, Guo said.

Currently, however, only 87 out of every 10,000 people donate blood in the Chinese mainland, far less than the 454 out of every 10,000 people in high-income countries and 101 in middle-income countries.

In addition to mistrust, many still doubt the safety of the donating process and fear getting infected by HIV, though the government has repeatedly assured the public of the safety at licensed blood-collecting centers.

Previous reports indicated that the main source of donated blood in China was still organized college students and migrant workers, which accounted for 60 percent of total donors.

Last year, a national blood shortage occurred and caused a wide range of surgeries to be postponed.

The country's health minister donated blood in late October 2010 and called on the public to do the same.

To cope with the risk of a future blood shortage, several central government departments issued a notice to host a month-long national campaign in December to promote blood donations through mass media and public institutions.

Another major responsibility lies with the managing system inside blood centers and medical institutions, Guo said, specifying that they should upgrade their protocols and training to achieve full and effective use of donated blood.