However, the impact of the Cultural Revolution on accessible education varied among regions, and formal measurements of literacy did not resume until the 1980s. Some counties in Zhanjiang had illiteracy rates as high as 41% some 20 years after the revolution. The leaders of China at the time denied that there were any illiteracy problems from the start. This effect was amplified by the elimination of qualified teachers—many districts were forced to rely on selected students to educate the next generation. Though the effect of the Cultural Revolution was disastrous for millions in China, there were positive outcomes for some sections of the population, such as those in rural areas. For example, the upheavals of the Cultural Revolution and the hostility to the intellectual elite is widely accepted to have damaged the quality of education in China, especially at the upper end of the education system. However, the radical policies also provided many in rural communities with middle school education for the first time, which is thought to have facilitated the rural economic development in the 70s and 80s.> Similarly, many health personnel were deployed to the countryside as barefoot doctors during the Cultural Revolution. Some farmers were given informal medical training, and health-care centers were established in rural communities. This process led to a marked improvement in the health and the life expectancy of the general population.