1 June 2022, 17:00 hours; Rome
Hazard: Influenza A(H7N9) virus with pandemic potential.
Country: China; imported cases in Malaysia (1) and Canada (2).
Number of human cases: 1,568 confirmed; 616 deaths (since February 2013).
New findings in birds / environment since last update (01 December 2021):0
New human cases since last update (01 December 2021): 0
Map 1. Human cases and positive findings in birds or the environment in China
Note: Human cases are depicted in the geographic location where they were reported; for some cases, exposure may have occurred in a different geographic location. Centroid geo-coordinates were used for H7N9 positive animal/environment samples where the precise geolocation is unknown.
Provinces/municipalities affected (since 2013): Beijing, Chongqing, Shanghai and Tianjin Municipalities; Anhui, Fujian, Gansu, Guangdong, Guizhou, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Qinghai, Shaanxi, Shanxi, Shandong, Sichuan, Taiwan, Yunnan and Zhejiang Provinces; Hong Kong SAR, Macao SAR; Guangxi, Inner Mongolia, Ningxia Hui, Tibet and Xinjiang Uyghur Autonomous Regions (China); Sabah (Malaysia); British Columbia (Canada).
Highly pathogenic virus findings: Since 10 January 2017, highly pathogenic avian influenza (HPAI) type H7N9 virus was detected in a total of 66 poultry or environmental samples (46 chickens, 8 peacocks, 2 duck and 10 environmental samples); H7N9 virus isolates from 32 human cases were found to be HPAI virus.
Province | LBM* | Farm | Backyard | Others** | Total |
---|---|---|---|---|---|
Anhui |
0 |
1 |
0 |
0 |
1 |
Fujian |
1 |
0 |
0 |
0 |
1 |
Guangdong |
22 |
0 |
0 |
0 |
22 |
Guangxi |
0 |
1 |
0 |
0 |
1 |
Hebei |
0 |
1 |
0 |
0 |
1 |
Heilongjiang |
0 |
1 |
0 |
0 |
1 |
Henan |
0 |
1 |
0 |
0 |
1 |
Hunan |
3 |
1 |
1 |
0 |
5 |
Liaoning |
0 |
1 |
0 |
1 |
2 |
Inner Mongolia |
0 |
2 |
0 |
0 |
2 |
Ningxia Hui |
0 |
2 |
0 |
0 |
2 |
Shaanxi |
0 |
2 |
0 |
0 |
2 |
Shanxi |
0 |
1 |
0 |
0 |
1 |
Tianjin |
0 |
1 |
0 |
0 |
1 |
Unknown |
0 |
0 |
0 |
1 |
1 |
TOTAL |
26 |
15 |
1 |
2 | 44 |
*LBM: live bird market; **Others include one airport and one zoo.
Animal/environmental findings: Since 4 April 2013 around 2500 virological samples from the environment, chickens, pigeons, ducks, turkeys, peacocks, a tree sparrow and a magpie robin tested positive; positives mainly from live bird markets, vendors and some commercial or breeding farms.
Table 2. National H7N9 surveillance and post-vaccination monitoring results from January 2020 to September 2021 published by MARA, China
Reporting period | #serum samples collected from birds | Average post-vaccination monitoring immunization rate (target 70%) | #virological samples collected from birds and the environment | #H7N9 positive virological samples |
---|---|---|---|---|
2020 |
||||
January |
72 845 |
96.24 |
17 536 |
0 |
February |
107 409 |
94.27 |
34 501 |
0 |
March |
127 074 |
95.05 |
42 190 |
0 |
April |
104 650 |
95.34 |
24 017 |
0 |
May |
180 261 |
95.59 |
21 961 |
3 |
June |
221 577 |
95.77 |
31 183 |
0 |
July |
166 193 |
92.32 |
43 404 |
0 |
August |
110 926 |
96.08 |
17 053 |
0 |
September |
106 163 |
95.67 |
16 410 |
0 |
October |
78 070 |
95.15 |
11 647 |
14 |
November |
168 938 |
95.87 |
32 425 |
0 |
December |
302 599 |
94.21 |
84 929 |
0 |
2021 |
||||
January |
96 733 |
95.70 |
31 780 |
0 |
February |
67 509 |
94.99 |
29 836 |
0 |
March |
78 760 |
95.77 |
20 481 |
0 |
April |
89 500 |
89.96 |
17 821 |
0 |
May |
128 826 |
94.48 |
20 759 |
0 |
June |
213 902 |
94.70 |
52 273 |
0 |
July |
170 840 |
94.78 |
36 193 |
0 |
August |
101 929 |
95.01 |
31 747 |
0 |
September |
102 355 |
94.21 |
25 924 |
0 |
Source: Published by MARA, China. Note: sample sizes and collection sites can vary significantly from one administrative region to another. Detailed results can be consulted on the official website of the Ministry of Agriculture and Rural Affairs, China [reference].
Figure 1. Number of positive virological samples from birds or the environment, by province and origin as of 02 February 2022
Data include both high and low pathogenic H7N9 viruses.
Figure 2. Distributions of low* and highly pathogenic H7N9 virologically positive samples (nLPAI=246; nHPAI=44)
Note: * May contain unconfirmed HPAI at the time of publishing. Samples collected from birds or the environment, by sampling location, between October 2016 and 02 February 2022. Samples from the same location and time are grouped. Some data on H7N9 positive virological samples collected during national H7N9 surveillance could not be included due to absence of information on the sampling location and the sample origin.
Figure 3. Distributions of low* and highly pathogenic H7N9 virologically positive samples (nLPAI=297; nHPAI=50)
Note: * May contain unconfirmed HPAI at the time of publishing. Samples collected from birds or the environment, by sample origin between October 2016 and 02 February 2022. Samples from the same origin, location and time are grouped. Some data on H7N9 positive virological samples collected during national H7N9 surveillance could not be included due to absence of information on the sampling location and the sample origin.
Figure 4. Number of officially reported human cases since February 2013, as of 02 February 2022
Data include both high and low pathogenic H7N9 viruses.
Figure 5. Incidence of officially reported human cases by quarter, based on onset date from February 2013 (beginning of period 5) to 02 February 2022
Note: For cases with unknown onset dates from period 5 (n=55), reporting dates were used instead. Both high and low pathogenic H7N9 viruses are included. Each period starts on 1 October and ends on 30 September of the next year.
He, D., Gu, M., Wang, X., Wang, X., Li, G., Yan, Y., […], & Liu, X. Spatiotemporal Associations and Molecular Evolution of Highly Pathogenic Avian Influenza A H7N9 Virus in China from 2017 to 2021. Viruses, 13(12), 2524. [reference]. In this study, 10 new strains of highly pathogenic avian influenza (HPAI) H7N9 virus subtype from October 2019 to April 2021 were sequenced. HPAI H7N9 virus subtype was primarily circulating in Northern China since period six (October 2017 – September 2018). HPAI H7N9 virus phylogenies exhibit a geographical structure compatible with high levels of local transmission after unidirectional rapid geographical expansion towards the north of China in 2017. Two major subclades were continually expanding with the viral population size undergoing a sharp increase after 2018 with an obvious seasonal tendency.
Tang, H., Kang, J., Shen, C., Wang, Y., Robertson, I. D., Cai, C., […], & Bruce, M. Benefit-cost analysis of a H7N9 vaccination program in poultry in Guangxi, China. Preventive veterinary medicine, 200, 105580. Advance online publication. [reference]. This study was designed to evaluate the economic value of the H7N9 vaccination program in Guangxi by assessing the benefits and costs of the program compared to not vaccinating against H7N9. A benefit-cost analysis was undertaken to evaluate the adoption of a vaccination program against H7N9 in each of three consecutive years from July 2017 to June 2020 with the baseline scenario (the absence of H7N9 vaccination in the 12-month period July 2016 to June 2017). Results demonstrate the significant economic advantage of implementing a vaccination program against H7N9 in Guangxi.
Information provided herein is current as of the date of issue. Information added or changed since the last H7N9 situation update appears in orange. Human cases are depicted in the geographic location of their report. For some cases, exposure may have occurred in one geographic location but reported in another. For cases with unknown onset date, reporting date was used instead. FAO compiles information drawn from multiple national (Ministries of Agriculture or Livestock, Ministries of Health, Provincial Government websites; Centers for Disease Prevention and Control [CDC]) and international sources (World Health Organization [WHO], World Organisation for Animal Health [WOAH]), as well as peer-reviewed scientific articles. FAO makes every effort to ensure, but does not guarantee, accuracy, completeness or authenticity of the information. The boundaries and names shown and the designations used on these map(s) do not imply the expression of any opinion whatsoever on the part of FAO concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers and boundaries. Dashed lines on maps represent approximate border lines for which there may not yet be full agreement.
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