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Blindness as a public health problem in China

Global Initiative for the Elimination of Avoidable Blindness

Fact sheet N°230

China accounts for about 18% of the world's blind. The country is estimated to have the largest number of blind people in the world – around 5 million. By definition, these people cannot walk about unaided.

Against the background of a huge population, estimated by the UN at some 1267 million people, these figures do not look impressive. Indeed, the current prevalence of blindness in China – the total number of blind people at any given time expressed as a percentage of the total population -- is around 0.4%. However, in absolute terms, the country's ever-increasing blind population has already surpassed the total population in such countries as Denmark, Finland or Norway.

In China, blindness is not only a public health and social problem. Apart from the unspeakable suffering and hardship that it has brought upon these millions of people and their immediate families, this condition is a serious drain on the national economy. However, any attempt to arrive at the total direct and indirect costs of blindness to the Chinese economy will be guesswork. Such statistics do not exist in the country.

For comparison, in 1990, the total cost of blindness to the federal budget in the USA was estimated to be around US$4.1 billion. It was also estimated that if all the avoidable blindness in persons under 20 and working-age adults were prevented, a potential saving of US$1.0 billion per year would accrue to the federal budget.

In a study from India in 1989, such costs, including a minimal subsistence allowance for the blind, were estimated at some US$4.6 billion per year.

Globally, the aggregated costs of blindness to the world economy were put at some US$25 billion.

Causes of blindness

The major causes of blindness in China include cataract, cornea diseases, trachoma, glaucoma and a number of factors contributing to blindness in children.

The main cause of blindness in China today is cataract -- a condition that refers to a clouding of the crystalline lens of the eye. It is predominantly a disease associated with ageing. Cataract is responsible for approximately 50% of the country's blind, or around 2.5 million people. Each year, around 400 000 people become totally blind because of cataracts alone.

Trachoma is still endemic in certain parts of China. Of the thirty-one provinces in the country, the disease is reported in eight. Trachoma blindness prevalence of 0.1% is reported in the Henan Province. The disease is the second cause of blindness after cataract in the Shandong Province and the third one in the Hunan and Yunnan Provinces. It is also considered a public health problem in the Fujian and Hebei Provinces. Trichiasis surgeries are still performed in the Anhui and Gansu Provinces.

Blindness in Chinese children is mainly caused by vitamin A deficiency, measles, conjunctivitis in the newborn, congenital cataract and retinopathy of prematurity (ROP). Of an estimated 1 million blind children in Asia, some 400 000 probably live in China.

According to the UN and WHO, vitamin A deficiency remains a public health problem in China. It will remain so even after the year 2000 – the target year for the elimination of blindness resulting from vitamin A deficiency, which was ambitiously set by the World Summit for Children in 1990. ROP blindness is emerging as a problem in the country because of the ever-increasing survival of low and very low birth weight infants.

National efforts

In 1949, when the Peoples' Republic of China came into existence, the principal causes of blindness were infectious eye diseases (mainly trachoma), vitamin A deficiency, trauma and glaucoma. The prevalence of trachoma – a disease associated with poor housing, sanitation and hygiene -- was as high as 50%, reaching 90% in remote rural areas of China.

From its inception the new State and the national authorities at all levels made great efforts to prevent and treat trachoma, which was declared a public health priority.

Ophthalmologists throughout the country responded enthusiastically and actively participated in these nationwide efforts. As a result, in the 1960's the prevalence and severity of trachoma was significantly reduced throughout the country. However, during the ten years of the Cultural Revolution, blindness prevention efforts in China were discontinued. They were reinitiated only in the 1980's.

In 1984, blindness prevention in China received a new impetus. The Government established a National Steering Group for the Prevention of Blindness that has subsequently developed a "Nationwide Working Programme for Blindness Prevention and Primary Eye Care, 1991-2000". In 1996, at the initiative of the Ministry of Health, supported by other ministries, June 6 was declared to be the annual National Eye-Care Day, a move that has played a significant role in mobilizing the public at large and national authorities at all levels for blindness prevention.

An epidemiological survey in the early 80s was the first to suggest that the principal cause of blindness in China was no longer trachoma but cataracts.

Blindness prevention and treatment projects, which focused on screening and surgical intervention for cataracts, were initiated in all parts of the country. The China Disabled Persons' Federation – an influential nationwide organization catering for the needs of an estimated 20 million people with disabilities -- began promoting cataract surgery throughout the country.

In 1988, the State Council approved the "Five-year Working Programme of Activities for China's Disabled Persons". The Programme set a target of 500 000 cataract surgeries in the five years that followed. The Outline of the "Eighth Five-year Plan of Activities for China's Disabled Persons", approved by the State Council in 1991, stipulated for 600 000 cataract operations between 1991 and 1995.

The goal of the Chinese Ministry of Health over the coming years is to reduce the prevalence of blindness in the country to less than 0.3%, i.e. almost by half. Special emphasis in the prevention of blindness in China is placed on improving the quantity and quality of cataract surgeries, as well as on intensifying efforts to avoid eye injuries in the workplace (within an occupational health programme) and among children (within a school health education programme).

Cataract, human resources and eye care delivery

Cataract blindness in China reflects the overall problems the country is facing in the eye care delivery.

At present, China has some 126 million people over 60 years of age. The country is also estimated to have the highest growth rate of the elderly population in the world. By 2020, the group of older people is projected to increase by 90% and reach 240 million people. This estimated increase would place China on top of the list of five developing countries that are expected to have the largest elderly populations in the world by 2020.

Age-related conditions in China, such as vision loss due to cataract, will increase accordingly if no preventive actions are taken. The Chinese Ministry of Health estimates that if the current trends remain unchanged, the number of people blind from cataract alone will more than double, reaching over 5 million by 2020, while the overall number of China's blind will increase four times.

The number of cataract operations per million population per year (Cataract Surgical Rate or CSR) is illustrative of the delivery of eye care in any country. Today, an estimated 360000 cataract operations are performed in China, giving the average national CSR of 290 per million population per year.

This rate is higher than in Africa (200) but particularly low if compared to the established market economies, where it ranges between 3000 and 5000. On the other hand, the CSR in China is steadily on the rise. It was estimated to be 136 in 1994 and 192 in 1997. In certain provinces, the CSR is already considerably higher than the average national rate.

Lack of adequately trained eye care practitioners seems to be the main bottleneck. There is an estimated 22 000 eye doctors in China, who have different levels of training and experience. About 50% of them practice cataract surgery. This means that the country probably has only around 5-7 cataract surgeons per million population or 1 per 150 000 -- 200 000 population.

In addition, the distribution of surgically active ophthalmologists is very uneven. Most of them are found in urban settings, while more than 70% of the population lives in the rural areas.

On average, of the 2400 county hospitals scattered throughout the country, 45% do not have a trained cataract surgeon. In some provinces, such as Xinjiang, Tibet and Hunan, this percentage is even higher, often reaching 75%. The situation at the county level is frequently further complicated by the lack of appropriate equipment and supplies.

Nevertheless, from 1988 to 1996, an estimated 1.75 million sight-recovering cataract surgeries was performed in China. However, two randomized sample surveys (in the Shunyi District, Beijing, and in the Doumen County, Guangdong Province) carried out in 1996 revealed that in more than 10% of these cases the outcome of the operation was poor. In the operated patients, the sight was either not restored, or they continued to have low vision. The surveys showed that the lower than expected quality of cataract surgery was not an isolated phenomenon.

One of the reasons is the lack of practical knowledge about and supply of intraocular lenses, which are successfully used in cataract surgery in developed countries.

As a result, the cataract surgical coverage in China chronically lags behind the expected needs by some 80%. The current backlog of urgent cataract cases, which require surgical intervention, exceeds 2 million.

International response

WHO has always recognized blindness and visual impairment as a public health problem in many countries, both developed and, particularly, developing. However, for a long time, the magnitude of the problem could not be assessed, and meaningful global and regional prevention activities could not be initiated for lack of epidemiological data.

The first task faced by the WHO Programme for the Prevention of Blindness (PBL), created in 1978, was to prepare reliable estimates of prevalence of blindness and visual disability worldwide. In response to this challenge, PBL developed internationally acceptedsimple population assessment methodologies to measure prevalence of visual loss and identify its causes. Standard low-cost field surveys, designed by WHO and conducted mainly by trained non-specialist staff, provided the badly needed epidemiological data and helped arrive at national blindness estimates.

On the basis of national data, regional and global estimates were prepared and used in the development of the WHO Global Data Bank on Blindness, an indispensable tool for planning international action to prevent or treat blindness.

PBL started its work in China in 1981. It supported and assisted the Chinese health authorities in epidemiological surveys on blindness and its causes in many provinces. As a result of these collaborative efforts, the true picture of blindness in the country began to emerge. In 1986, a WHO Collaborating Centre was established at the Institute of Ophthalmology in Beijing. Thus, the foundation was laid for further collaborative research and training activities.

At the same time, in cooperation with leading scientists, institutions and collaborating organizations, WHO continued to develop strategies and technical standards for control of specific blinding diseases. Scientifically sound, field-tested and regularly updated, these strategies were gradually gaining worldwide acceptance.

For example, the "SAFE" strategy for the elimination of trachoma is of special relevance to China, where foci of the blinding disease persist in a number of provinces. "SAFE" stands for Surgery for trichiasis (inturned eyelashes), Antibiotics, Facial cleanliness and Environmental improvement. It consists of a combination of public health interventions, which seek community participation and involvement.

A WHO Alliance for the Global Elimination of Trachoma (GET 2020) was established in 1997, which constitutes an integral part of Vision 2020.

WHO-developed strategies have been adopted by governments, international agencies, nongovernmental development organizations, as well as Foundations in their every-day work to prevent and treat blindness.

Nongovernmental development organizations (NGDOs)

NGDOs have been playing an increasingly important role in blindness prevention worldwide. In developing countries, the NGDO network is currently spending an estimated US$80 million per year on blindness prevention and treatment.

At present, there are 12 NGDOs actively collaborating with WHO and the Ministry of Health and supporting eye care delivery in 19 of the 31 provinces in China. Among them (in alphabetical order):

  • Amity Foundation (China)
  • Asia Foundation for the Prevention of Blindness (Hong Kong, China)
  • Christoffel-Blindenmission (Christian Blind Mission International (CBM), Germany)
  • Foresight (Australia)
  • Foundation for Eye Care Himalaya (The Netherlands)
  • The Fred Hollows Foundation (Australia)
  • Helen Keller International (USA)
  • The Lions Club International (USA)
  • ORBIS International (USA)
  • Singapore National Eye Centre (Singapore)
  • Seva Foundation (USA)
  • Tibet Vision Project (USA)

With rare exceptions, all these NGDOs have agreed to work together within Vision 2020 towards the common goal of eliminating avoidable blindness in China by the year 2020.

There are other NGDOs, like Health Hong Kong Foundation, which are working independently with the Ministry of Heath.

The NDGOs working within Vision 2020 will concentrate on developing model projects for delivery of high-volume, good quality and affordable cataract services and eye care at the county hospital level. Such efforts will require programmes to train Chinese cataract surgeons and provide assistance to the Chinese Ministry of Health and China Disabled Persons' Federation with appropriate equipment and technologies. These organizations will also continue to support the delivery of cataract operations.

Training activities will be carried out with emphasis on counties without a cataract surgeon, where trainee ophthalmologists will be identified on the understanding that they will return to work in their own county. A uniform certification of competence for cataract surgery will be developed in consultation with the Chinese Ministry of Health.

Some of the NDGOs will continue to be involved in the prevention and treatment of trachoma and vitamin A deficiency.

For more information contact:

WHO Media centre
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