Human-Animal Interface

A human-animal interface describes the transmission of virus infections from animals to humans. Most of the known cases involved direct or indirect contact with infected live or dead birds. In most cases, humans can be affected by avian, swine, and other zoonotic influenza viruses. They can cause diseases in humans from mild upper respiratory infection, such as fever and cough, to severe pneumonia and death. These viruses are included in influenza type A. They are the most significant for public health because they can cause influenza pandemic like it was already with the Spanish flu of 1918 and 2009 swine flu pandemics.

We have turned to the publications on human-animal interfaces. For the review, we have performed a systematic search in the scientific literature database Scopus and have built a map of publications based on their reference lists (Figure 1). Proximity in this map and belonging to the same cluster mean that the papers cite the same publications, therefore the papers are likely to consider similar issues. The map is built using VOSviewer software.

The papers roughly split into five clusters:

• navy, center: epidemiology, virology and genetic analyses (coronaviruses and other viruses),
• purple, top right: swine viruses,
• yellow, bottom right: avian viruses,
• blue, second from the left: opportunistic infections.
• light blue, on the left: hepeviridae viruses (hepatitis E viruses).

The majority of publications are located on the right side of the map. Purple cluster (top right) and yellow cluster (bottom right) are proximately located because both of them are about influenza. They are located close to the navy cluster (center) because it contains publications that describe pathogens with the greatest zoonotic potential, such as influenza virus A. Blue (second from the left) and light blue (on the left) clusters are located distantly from purple and yellow clusters because they are about different types of infections with different subsequent diseases, therefore their reference lists rarely overlap.

Cluster description

Navy cluster reviews different types of viruses such as henipavirus, rotaviruses, and coronaviruses. A lot of publications are about virology and genetic diversity of viruses, especially about their genomes. Many works also describe the emergence and resurgence of viruses, their epidemiology, and how they are transmitted. Particular attention is paid to viruses transmitted by bats. These works are located at the bottom of the cluster. As for the coronaviruses, a lot of the works trace the transmission from camels to humans.

Purple cluster devoted to swine viruses contains a lot of publications that tell about the need for increased surveillance and further research. Many publications are connected to the recent pandemic in 2009.

Yellow cluster on avian viruses covers their epidemiology, origins, transmission, causes, and their potential. Some publications also describe genetics and molecular structure.

Light-blue cluster represents the family of viruses hepeviridae and the main disease that they cause – hepatitis E. Publications cover the origins, characteristics, modes of transmission, consequences, and prevention. Most of the publications study swine hosts. Most of the research in this cluster was published in the 1990s. The most cited publication describes the connection between novel swine hepatitis E virus and the human hepatitis E virus (Meng et al. 1997).

Blue cluster is about opportunistic infections that are caused by pathogens and usually only affect people with a weakened immune system (taking the opportunity of it – hence the name). The majority of publications study people with HIV and cancer. Publications also describe molecular epidemiology and genetic characteristics of these infections.

General reviews on human-animal interfaces

• Greger, Michael. 2007. ‘The Human/Animal Interface: Emergence and Resurgence of Zoonotic Infectious Diseases’. Critical Reviews in Microbiology 33(4):243–99.
• Jones, Kate E., Nikkita G. Patel, Marc A. Levy, Adam Storeygard, Deborah Balk, John L. Gittleman, and Peter Daszak. 2008. “Global Trends in Emerging Infectious Diseases.” Nature 451(7181):990–93.
• Lloyd-Smith, James O., Dylan George, Kim M. Pepin, Virginia E. Pitzer, Juliet R. C. Pulliam, Andrew P. Dobson, Peter J. Hudson, and Bryan T. Grenfell. 2009. ‘Epidemic Dynamics at the Human-Animal Interface’. Science 326(5958):1362–67.
• Morens, David M., Gregory K. Folkers, and Anthony S. Fauci. 2004. ‘The Challenge of Emerging and Re-Emerging Infectious Diseases’. Nature 430(6996):242–49.
• Taylor, Louise H., Sophia M. Latham, and Mark E. J. Woolhouse. 2001. “Risk Factors for Human Disease Emergence.” Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 356(1411):983–89.
• Woolhouse, Mark E. J., and Sonya Gowtage-Sequeria. 2005. “Host Range and Emerging and Reemerging Pathogens.” Emerging Infectious Diseases 11(12):1842–47.

On page 2 we provide links to the key papers in each cluster.