Pandemics: From uncertainty to identifying risks and preparedness

When a mysterious and deadly disease spread around the world in 1918, people rapidly realized it was like nothing they had seen before and they were not prepared to protect themselves. This was considered a big disappointment since the field of infectious diseases had made some major breakthroughs; in 1796 Edward Jenner developed a vaccine that could prevent small pox, Pasteur and Koch had solidified the germ theory of diseases and many bacteria causing various infectious diseases, including tuberculosis, had been identified.

Uncertainty remains
Even now, with all our additional knowledge, we cannot predict when and where the next influenza pandemic will start. Furthermore, it will take months to develop, test and distribute a vaccine. Given that most people in 1918 died within the first 6 months of the pandemic, it is likely that the vaccine will come too late for many of us in a present-day pandemic.

Identify risks
We now know that new influenza viruses jump from animals, like birds and pigs, into the human population. So, people who are in close contact with poultry or pigs, are at risk to be among the first infected with a new potentially pandemic influenza virus.

By studying individuals at high risk for hospitalization and/or death during past influenza pandemics and seasonal epidemics, we can identify the risk groups for our future pandemics. Today’s aging population will form the traditional high-risk group. During the 1918 pandemic mortality rates were higher among native populations including Aboriginals, Maori and Alaskan natives and among people suffering from malnutrition due to famine. These groups are still at a high risk for hospitalization during seasonal epidemics and were also identified as high-risk groups during the 2009 pandemic.

By studying seasonal epidemics, we now observe new modern-day risk-groups like the obese, diabetics and people living with cardiovascular disease or asthma.

Preparedness
We may not be able to predict when and where the next pandemic will start, however compared to 1918, we now have established a surveillance network that aims to stop any new influenza virus that jumps from animals to humans before it spreads from human-to-human. Nevertheless, we need to prepare ourselves in case a new virus does spread within the human population.

In the absence of an “of-the-shelf” pandemic vaccine, we could anticipate the next pandemic by improving people’s general health and thereby decreasing the number of people living with high-risk conditions like obesity or diabetes. Furthermore, we know that measures which aim to limit viral spread are most effective when they are implemented early. It is therefore important for governments and those in authority to gain public trust and build public knowledge before the next major pandemic outbreak. This will ensure that the public knows what to expect, how to act and is likely to improve compliance with preventative measures in a pandemic scenario. Early implementation of those measures will buy us time until sufficient vaccines are available.

Carolien Van de Sandt
Postdoctoral Research Fellow, The Peter Doherty Institute for Infection & Immunity
1.10pm – 1.50pm
Tuesday 24 September