Dataset Information

High Risk of Influenza Virus Infection Among Swine Workers: Examining a Dynamic Cohort in China.

ABSTRACT:

Background

China is thought to be a hotspot for zoonotic influenza virus emergence, yet there have been few prospective studies examining the occupational risks of such infections.

Methods

We present the first 2 years of data collected from a 5-year, prospective, cohort study of swine-exposed and -unexposed participants at 6 swine farms in China. We conducted serological and virological surveillance to examine evidence for swine influenza A virus infection in humans.

Results

Of the 658 participants (521 swine-exposed and 137 swine-unexposed), 207 (31.5%) seroconverted against at least 1 swine influenza virus subtype (swine H1N1 or H3N2). Swine-exposed participants' microneutralization titers, especially those enrolled at confined animal feeding operations (CAFOs), were higher against the swine H1N1 virus than were other participants at 12 and 24 months. Despite elevated titers, among the 187 study subjects for whom we had complete follow-up, participants working at swine CAFOs had significantly greater odds of seroconverting against both the swine H1N1 (odds ratio [OR] 19.16, 95% confidence interval [CI] 3.55-358.65) and swine H3N2 (OR 2.97, 95% CI 1.16-8.01) viruses, compared to unexposed and non-CAFO swine workers with less intense swine exposure.

Conclusions

While some of the observed increased risk against swine viruses may have been explained by exposure to human influenza strains, study data suggest that even with elevated preexisting antibodies, swine-exposed workers were at high risk of infection with enzootic swine influenza A viruses.

SUBMITTER: Borkenhagen LK

PROVIDER: S-EPMC7108185 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

High Risk of Influenza Virus Infection Among Swine Workers: Examining a Dynamic Cohort in China.

Borkenhagen Laura K LK Wang Guo-Lin GL Simmons Ryan A RA Bi Zhen-Qiang ZQ Lu Bing B Wang Xian-Jun XJ Wang Chuang-Xin CX Chen Shan-Hui SH Song Shao-Xia SX Li Min M Zhao Teng T Wu Meng-Na MN Park Lawrence P LP Cao Wu-Chun WC Ma Mai-Juan MJ Gray Gregory C GC

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 20200701 3

<h4>Background</h4>China is thought to be a hotspot for zoonotic influenza virus emergence, yet there have been few prospective studies examining the occupational risks of such infections.<h4>Methods</h4>We present the first 2 years of data collected from a 5-year, prospective, cohort study of swine-exposed and -unexposed participants at 6 swine farms in China. We conducted serological and virological surveillance to examine evidence for swine influenza A virus infection in humans.<h4>Results</h ...[more]

PMID: 31504322

Similar Datasets

Project description:BackgroundWithin the last decades industrial swine herds in Europe grown significantly, creating an optimized reservoir for swine influenza A viruses (swIAV) to become enzootic, particularly in piglet producing herds among newborn, partly immunologically naïve piglets. To date, the only specific control measure to protect piglets from swIAV is the vaccination of sows, which provides passive immunity through maternally derived antibodies in colostrum of vaccinated sows. Interruption of infection chains through management practices have had limited success. This study focused on weaned piglets in five enzootically swIAV infected swine herds in North-West and North-East Germany and aimed to better understand swIAV infection patterns to improve piglet protection and reduce zoonotic risks. Participating farms fulfilled the following inclusion criteria: sow herd with ≥ 400 sows (actual size 600-1850 sows), piglets not vaccinated against influenza A virus and a history of recurrent respiratory problems associated with continuing influenza A virus infection. Influenza vaccination was performed in all sow herds, except for one, which discontinued vaccination during the study.ResultsFirst swIAV detections in weaned piglets occurred at 4 weeks of age in the nursery and continued to be detected in piglets up to 10 weeks of age showing enzootic swIAV infections in all herds over the entire nursery period. This included simultaneous circulation of two subtypes in a herd and co-infection with two subtypes in individual animals. Evidence for prolonged (at least 13 days) shedding was obtained in one piglet based on two consecutive swIAV positive samplings. Possible re-infection was suspected in twelve piglets based on three samplings, the second of which was swIAV negative in contrast to the first and third sampling which were swIAV positive. However, swIAV was not detected in nasal swabs from either suckling piglets or sows in the first week after farrowing.ConclusionsPredominantly, weaned piglets were infected. There was no evidence of transmission from sow to piglet based on swIAV negative nasal swabs from sows and suckling piglets. Prolonged virus shedding by individual piglets as well as the co-circulation of different swIAV subtypes in a group or even individuals emphasize the potential of swIAV to increase genetic (and potentially phenotypic) variation and the need to continue close monitoring. Understanding the dynamics of swIAV infections in enzootically infected herds has the overall goal of improving protection to reduce economic losses due to swIAV-related disease and consequently to advance animal health and well-being.

Dataset Information

High Risk of Influenza Virus Infection Among Swine Workers: Examining a Dynamic Cohort in China.

Background

Methods

Results

Conclusions

Publications

High Risk of Influenza Virus Infection Among Swine Workers: Examining a Dynamic Cohort in China.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets