Recommended Vaccines: No vaccines are specifically required by China unless you are coming from a yellow fever-infected country. Canadian and US disease control and prevention authorities recommend that you have current polio and tetanus immunizations. For traveling into the countryside and remote areas, immune globulin is also recommended to combat hepatitis A, as is a vaccine against typhoid.
Malaria: You will not be at risk in cities and popular tourist areas. Rural areas can present a risk in these provinces: Anhui, Fuijan, Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Jiangsu, Jiangxi, Shandong, Sichuan, Tibet (Zangbo River valley only), and Yunnan. Transmission exists in rural communities below 4,921 feet (1,500 m) only during warm weather. South of latitude 25° N, however, transmission occurs year-round. The antimalaria treatment varies depending upon where you're going in this big country. Take only atovaquone/proguanil or doxycycline along the China-Burma border in the western part of Yunnan; atovaquone/proguanil or doxycycline or mefloquine in Hainan and the other parts of Yunnan province. Chloroquine in all other areas.
Other Issues: As with many countries you may visit, don't drink tap water or use ice in drinks, and bring along a supply of anti-diarrhea medicine, as well as any other prescription drugs required by your current health and medical situation. This is sound advice for anywhere you travel.