Human Rabies Epidemiology in Shandong Province, China

Human Rabies in China, 1960-2014: A Descriptive Epidemiological Study

Background

Rabies in China remains a public health problem. In 2014, nearly one thousand rabies-related deaths were reported while rabies geographic distribution has expanded for the recent years. This report used surveillance data to describe the epidemiological characteristics of human rabies in China including determining high-risk areas and seasonality to support national rabies prevention and control activities.

Methods

We analyzed the incidence and distribution of human rabies cases in mainland China using notifiable surveillance data from 1960–2014, which includes a detailed analysis of the recent years from 2004 to 2014.

Results

From 1960 to 2014, 120,913 human rabies cases were reported in mainland China. The highest number was recorded in 1981(0.7/100,000; 7037 cases), and in 2007(0.3/100,000; 3300 cases). A clear seasonal pattern has been observed with a peak in August (11.0% of total cases), Human rabies cases were reported in all provinces with a yearly average of 2198 from 1960 to 2014 in China, while the east and south regions were more seriously affected compared with other regions. From2004 to 2014, although the number of cases decreased by 65.2% since 2004 from 2651 to 924 cases, reported areas has paradoxically expanded from 162 prefectures to 200 prefectures and from southern to the central and northern provinces of China. Farmers accounted most of the cases (65.0%); 50–59 age group accounted for the highest proportion (20.5%), and cases are predominantly males with a male-to-female ratio of 2.4:1 on average.

Conclusions

Despite the overall steady decline of cases since the peak in 2007, the occurrence of cases in new areas and the spread trend were obvious in China in recent years. Further investigations and efforts are warranted in the areas have high rabies incidence to control rabies by interrupting transmission from dogs to humans and in the dog population. Furthermore, elimination of rabies should be eventually the ultimate goal for China.

China is a high-risk environment for rabies, with human rabies cases second only to India globally. This paper reviews 55 years of rabies epidemiology in mainland China, and detailed analysis of data in recent years. In this study, notifiable surveillance data were analyzed and found that rabies still remains a serious public health problem in China, the east and south regions were more seriously affected compared with other regions, however, the occurrence of cases in new areas and the spread trend were obvious in China in recent years. Moreover, males in rural areas had higher risk of infection than residents in urban areas, a clear seasonal pattern has been observed with a peak in August. These findings indicated a clear need to increase government and public consciousness with regard to the potential risk of rabies and the means of avoiding the disease. Further efforts should be strengthen specially in the high spot areas.

Human rabies in Zhejiang Province, China

OBJECTIVES

To explore the epidemiological characteristics of human rabies in Zhejiang Province, China.

METHODS

Descriptive and statistical analyses were performed using data collected through interview with human rabies cases or their relatives during 2007 to 2014. A standardized questionnaire was used to collect the data.

RESULTS

Two hundred and one cases of human rabies were diagnosed in Zhejiang Province between 2007 and 2014, with a gradually declining annual incidence. Of the rabies cases identified, 61.2% were aged 40-65 years, and the male to female ratio was 2.30:1; 63.7% of cases occurred in the summer and autumn. The two most reported occupations were farmer (69.2%) and rural laborer (15.4%). Wenzhou, Jinhua, and Huzhou were the three cities with the most reported cases. The majority of cases (92.8%) were attributed to canines, and 71.0% of animal vectors were household animals. Less than half of the cases (41.4%) sought wound treatment after exposure. Post-exposure passive immunization was given to 9.7% and active immunization to 2.3%. Cases with a wound on the head/face only had a significantly shorter incubation than those with wounds at other sites (p<0.05); cases with a wound on the hand only had a significantly shorter incubation than those with a wound on the lower limb below the knee only (p<0.001). Non-resident cases were significantly younger (p<0.001) and had a shorter disease duration (p=0.015) than locally resident cases.

CONCLUSIONS

The majority of rabies cases occurred among 40-65-year-old male residents of northern, mid-west, and southeast Zhejiang Province. Further health education is needed to increase the coverage of post-exposure prophylaxis (PEP) in people exposed to possible rabid animals and rabies vaccine use in household animals.