Pandemics: Past, present and future

Published: 2023-03-14

Just a year after the WHO added "Disease X" to their list of infectious disease threats, we were hit globally with the SARS-CoV-2 virus, COVID.

Professor Lone Simonsen. Photo by Ulrik Jantzen, published with consent from Roskilde University

As Professor of Epidemiology and head of the PandemiX Center at Roskilde University in Denmark, Lone Simonsen worked closely with Danish health authorities investigating and proposing ways to optimize efforts against the pandemic. In Sweden we had Anders Tegnell, whereas the Danes had “Corona Lone”. 

When invited to hold a lecture at the LUSEM Centre for Economic Demography, Lone Simonsen gave insights into the work at PandemiX, highlighting the work with Covid and how they made use of information on earlier pandemics.

“Basically, we took the phenomena of pandemics and put them on an imaginary autopsy table to see what they are all about. From how they emerge to what happens during the pandemic and how it ends,” says Lone Simonsen about her work at the PandemiX Center.

With COVID the Danish expert group tried to find out how pathogens evolved during the pandemic and how human interventions have affected the impact of it. It’s a very differentiated group spanning fields such as epidemiology, economic history, bioinformatics and mathematics just to mention a few areas. 

The Center studies the “Signature Features” of COVID-19 and past pandemics (influenza, cholera, smallpox). In essence that entails the use of mathematical models on historical data of past pandemics.

Among the signature elements of COVID were: 

  • The fact that a single virus bearer could infect many without him-/herself showing any symptoms, thus     making it harder to track. 
  • That the virus mutated several times and certain strains were more likely to infect people at a higher rate, whereas other strains gave graver symptoms. 
  • That unlike the Spanish flu of 1918 it hit the elderly population the hardest. In 1918 the older population had experienced the Russian flu pandemic of 1889 and were to an extent immune to the new one. 

“Also, now that we have better knowledge of pandemic signatures, we can become better at discovering them even with lesser data. This becomes important both in historical studies and when trying to identify a pandemic at an early stage,” says Lone Simonsen.

A group of researchers at the Department of Economic History at LUSEM are involved in a project under the umbrella of NORDEMICS, that is headed by Lone Simonsen. They are specifically looking into tuberculosis, and Doctoral student Liuyan Shi’s thesis will study different measures against tuberculosis and the long term intended and unintended effects of vaccination. Unintended effects may be protection against other diseases, like COVID for instance.  

Thanks to the extent of digitalized data, it was possible to map and analyse past pandemics. In the Nordic countries these types of data, can be traced back 300-400 years. Importantly, the societal context (wars, migration, mitigation strategies, etc) can also be studied to interpret observed patterns and impact.


About Nordemics

Professor Tommy Bengtsson, Associate Professor Luciana Quaranta, Doctoral student Liuyan Shi and Associate Professor Helene Castenbrandt at the Department of Economic History at LUSEM are involved in a project under the umbrella of Nordemics, that is headed by Lone Simonsen.

Nordemics is an interdisciplinary consortium with stakeholders from major universities in the Nordic countries. Its purpose is to study pandemics using data from up to 400 years of record-keeping in the Nordic countries. 

In Lund the primary focus is on early life infections and interventions, and their effects on later life health and socioeconomic outcomes. 


About Lone Simonsen

Lone Simonsen is an epidemiologist and Professor of Population Health Sciences, at the Department of Science and Environment at Roskilde University. She is also the director of the pandemic research centre, PandemiX. Lastly she holds a position as Research Professor in Global Health at George Washington University in Washington DC.    

Her research currently focuses on modeling historical and contemporary pandemics and emerging infectious diseases, population transitions to long healthy lives, "big data" in health, and vaccine program evaluation.