Zoonotic transmission of rotavirus: surveillance and control

Abstract

Group A rotavirus (Rotavirus A, RVA) is the main cause of acute dehydrating diarrhea in humans and numerous animal species. RVA shows vast diversity and a variety of human strains share genetic and antigenic features with animal origin RVA strains. This finding suggests that interspecies transmission is an important mechanism of rotavirus evolution and contributes to the diversity of human RVA strains. RVA is responsible for half a million deaths and several million hospitalizations worldwide. Globally, two rotavirus vaccines are available for routine use in infants. These vaccines show a great efficacy profile and induce protective immunity against various rotavirus strains. However, little is known about the long-term evolution and epidemiology of RVA strains under selective pressure related to vaccine use. Continuous strain surveillance in the post-vaccine licensure era is needed to help better understand mechanisms that may affect vaccine effectiveness.

Keywords:

• evolution
• interspecies transmission
• molecular epidemiology
• reassortment
• rotavirus A

Acknowledgements

The authors are grateful to Dr. Jon R, Gentsch, for critical reading of the manuscript.

Financial & competing interests disclosure

K Bányai was supported by the Hungarian Scientific Research Program (OTKA, T100727) and the Momentum Program (awarded by the Hungarian Academy of Sciences). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Key issues

• Rotavirus A (RVA) is a major cause of childhood diarrhea with significant mortality, mainly in developing countries. Vaccination is the primary strategy to reduce disease burden.

• Rotavirus vaccines are currently available worldwide and 77 countries have already introduced rotavirus vaccines in national immunization programs.

• Over the past three decades, global RVA strain surveillance programs identified numerous neutralization antigen type specificities associated with human infections, including 12 G and 17 P types in nearly 90 antigen combinations.

• New RVA diversity in humans comes, in part, from animal host species. Domestic livestock, companion animals and even feral animals may serve as reservoirs.

• Although prelicensure clinical trials and post-licensure surveillance indicate good homotypic (i.e., serotype-specific) and heterotypic protection, the question whether the marked genetic and antigenic diversity of RVA strains influences vaccine effectiveness over the long term remains open.

Notes