How Has Infectious Disease Incidence in China Changed Since the 2003 SARS Outbreak?

China has the world’s largest population. Not surprisingly, it also has a significant problem with infectious diseases.

In the first study to assess long-term infectious disease trends since the 2003 outbreak of severe acute respiratory syndrome (SARS) in the country, which garnered massive global attention, researchers from Zhejiang University have identified 55 million cases of infectious diseases in mainland China, and more than 130,000 fatalities resulting from them, just for the 10-year period between 2004 and 2013.

However, although their findings indicate that incidence increased over the study period—from 300.5 cases per 100,000 people in 2004 to 483.6 cases per 100,000 people in 2013—the authors note that the pace of that increase actually began to slow in 2009, from 6.2% annually from 2004 to 2008 to 2.3% annually from 2009 to 2013 (mortality rate also stabilized after 2009). The findings were published on April 12, 2017 in the journal The Lancet Infectious Diseases.

“In recent decades, the overall incidence and mortality of infectious diseases have shown a striking decline in China,” senior author Professor Lanjuan Li, MD, PhD, at Zhejiang University, said in a statement released with the publication. “This sharp fall is linked to effective new strategies to prevent and control the spread of infectious diseases in China.”

Dr. Li and colleagues believe these improvements can actually be traced to the SARS outbreak, which they note had highlighted flaws in the country’s disease prevention and control infrastructure. Indeed, since that time, officials in China have taken steps to improve the country’s water supply and sanitation and vector control strategies, while instituting more comprehensive immunization and screening programs. Of the 45 infectious diseases included in their analysis, 20 became less common over the study period, while only 10 became more common and 11 remained the same. Interestingly, 66% of the infectious disease cases recorded in the analysis could be traced to hand, foot and mouth disease, hepatitis B, and tuberculosis. However, the diseases with the highest increase in incidence over the study period were hydatid disease (24%), hepatitis C (19.2%), syphilis (16.3%), and HIV infection (16.3%), while those that caused the highest mortality rates were rabies, avian influenza A H5N1, and plague.

Although the authors credit China with significant improvements in public health, they note that significant challenges remain, including the need to enhance prevention, screening, and control measures in the nation’s more rural (and poor) areas as well as provide overall access to care among the poor population. In addition, they highlight the dual threats posed by antimicrobial resistance and increased travel—1 in 10 individuals in China move from poor, rural areas to cities for “better economic opportunities.”

“To counter the rise of hepatitis C, hydatid disease, syphilis, and HIV infection in China, we need improved screening, vector control, and immunisation, as well as reduced treatment costs," Dr. Li said in the statement. “The proportion of cases and deaths from various infectious diseases have shown changing patterns in the post-SARS era, and personalized strategies should be applied to benefit children, the elderly, men, and those living in high-risk regions.”

Brian P. Dunleavy is a medical writer and editor based in New York. His work has appeared in numerous healthcare-related publications. He is the former editor of Infectious Disease Special Edition.