Exploring the determinants of influenza A/H7N9 control intervention efficacy in China: Disentangling the effect of the ‘1110’ policy and poultry vaccination

Abstract

The influenza A virus of the H7N9 subtype (FLUAV H7N9) emerged in Eastern China provinces in 2013 causing illness in both poultry and humans. Most reported FLUAV H7N9 human cases were related to those associated with the live poultry market chain. From 2013 to 2017, there were five epidemic waves of human infections, and from the end of 2016, the number of human cases increased sharply. To control FLUAV H7N9 in the market chain, the so‐called ‘1110’ policy at live poultry markets and a national vaccination programme were implemented. The relative efficacy of these two measures on the number of poultry and human infections has not been quantified and compared. To explore their efficacy, a cross‐sectional study was conducted in six provinces of China, and the vaccination and surveillance data of H7N9 were analysed. Our survey data showed that poultry vendors were not widely aware of and did not accept the ‘1110’ policy. For subjective and objective factors, some measures of the ‘1110’ policy were not implemented in live bird markets (LBMs). However, the national vaccination programme achieved good immune effects and sharply decreased poultry FLUAV H7N9 infections. The detection rates of FLUAV H7N9 in LBMs and farms gradually decreased since the vaccination programme was implemented. Our analysis also indicated that human infections were closely related to poultry virus carriage rates; therefore, controlling FLUAV H7N9 circulation in poultry was an effective measure to control FLUAV H7N9 infections in humans. Although LBMs play a significant role in human infections, the management measures may not be implemented efficiently; hence, we need to conduct more investigations before developing related policies.

Research Note: Factors influencing highly pathogenic avian influenza preventive behavior among live poultry market vendors

“…LPM workers who obtain AI knowledge from multiple information channels are more likely to support government preventive measures than those who have fewer sources ( Lei, 2019 ). Insufficient disclosure of policy is also an important reason why management practices have not been successfully implemented in most markets ( Yi et al, 2022 ).…”

Novel technology to develop non-transmissible live influenza virus vaccines through alterations in M2/M42 ion channel expression

“…Following the emergence of Goose/Guangdong lineage H5N1 in China in 1996, H5 HPAIVs have spread world-wide and continue to cause severe morbidity and mortality in domestic poultry, as well as sporadic zoonotic infections. Due to the genetic and antigenic diversity of these viruses, many Southeast Asian countries have incorporated AIV vaccination into their control programs to reduce mortality, environmental shedding, transmission to other flocks, and reduce potential human exposure 14,50 . Faced with recent annual winter epidemics of H5NX HPAIV, many European countries are now considering vaccination of poultry and is also made available for use under a CC0 license.…”

Bayesian phylodynamics reveals the transmission dynamics of avian influenza A(H7N9) virus at the human–live bird market interface in China

“…Given the critical role of LBMs in the spread of H7N9 viruses, various interventions were implemented at LBMs in most affected areas to respond to the epidemic ( 16 , 20 – 22 ). In 2014, the Guangdong veterinary authority established the 1110 policy at LBMs, which involved daily cleaning, weekly disinfection, monthly rest day, and no overnight stay of poultry, and then, the Ministry of Agriculture and Rural Affairs (MARA) extended the policy to all provinces in February 2017 ( 23 ). Given the large number of human infections during wave 5 ( Fig.…”