Epidemics can have a devastating effect on people’s well-being and our prosperity. But something good can also come from it, scientists show.

It will not have escaped your notice: we are still in the middle of a pandemic. The culprit is SARS-CoV-2, a virus closely related to SARS-CoV-1, the pathogen that struck 29 different countries between 2002 and 2004 and claimed more than 700 lives. One of the hardest hit countries during this SARS-CoV-1 outbreak was China; in the country more than 5300 cases were reported and more than 300 people died.

Episodic Memory

The negative impact of the epidemic was large. But a new study now shows that the epidemic also had positive consequences. For example, the episodic memory of older Chinese who lived in a SARS-CoV-1 community between 2002 and 2004 appears to be much better years later than that of peers who were part of communities spared by SARS-CoV-1. .

Four years

“So at first glance, the impact that exposure to the SARS outbreak had on episodic memory was not that great,” said researcher Hongwei Xu. “It was only a difference of about 0.2 points on a 0-10 scale. In our data, however, that difference is equal to the difference that we normally see between the cognitive functioning of people who are four years apart in age. In other words, exposure to the SARS outbreak could cause the survivors to be cognitively about four years younger.”

The research

Xu and colleagues base their conclusions on data collected during a longitudinal study in China. During such a study, subjects are followed for a long period of time and examined repeatedly. The researchers focused on Chinese people who are 45 years or older at the time of the SARS-CoV-1 outbreak. Some of the subjects were part of a community where SARS-CoV-1 struck. For others, the virus didn’t come that close.

Episodic Memory

During the longitudinal study, the episodic memory of all subjects was repeatedly tested, among other things. This was done by reading a list of ten words to the subjects, after which the subjects were asked immediately and four minutes afterwards to name as many words as possible from the list. The researchers looked at the score of the older Chinese and looked at whether there were striking differences between the scores they had achieved before the epidemic and some time afterwards (in 2011). And so the scientists found that the episodic memory of the subjects for whom the SARS-CoV-1 virus had come very close was generally better than that of subjects for whom the virus was far-from-their-bed. show had stayed.

Surprising

It’s quite surprising, Xu thinks. “This is the second study in our research project to assess the long-term health impact of the epidemic,” explains Xu. “The initial study already surprised me, as we found that people who were part of communities affected by the SARS outbreak developed better health behaviors than those who lived in communities unaffected by SARS. These positive behavioral changes include an increase in regular physical activity. They also had an annual physical examination more often.” It was this first study that then set Xu and colleagues on the track for this second study. “The literature on the cognitive functioning of the elderly suggests that health behaviors such as regular physical activity can slow down cognitive decline. And so we thought it would be interesting to find out if the positive changes in behavior we saw in our previous study did indeed lead to better cognitive health among people confronted with SARS-CoV-1 within their community, but the survived the outbreak. And yet I was surprised to find a significant association between SARS exposure between 2002 and 2004 and better cognitive functioning among middle-aged Chinese and older in 2011.”

It’s not just the study results that surprised Xu. He was also amazed at how quickly we forgot about the SARS outbreak. “During our original literature review, we came across quite a few good studies published shortly afterwards dealing with the impact the SARS epidemic had on public health and the economy. There are many valuable lessons that we could have paid attention to in order to better prepare for and better combat the next epidemic or pandemic. I was surprised and disappointed that we (including myself) have failed to learn from this recent history.”

Psychosocial changes herald behavioral changes

The better episodic memory, according to the researchers, is most likely due to the fact that the Chinese positively changed their health behavior. “Our theory is that exposure to SARS – a new, contagious and deadly disease – led to fear, but also acted as a barrier for survivors. wake up call. In the wake of the SARS outbreak within their communities, the survivors may have experienced positive psychosocial changes. As a result, they valued their health and life more, their priorities changed and their relationships became more intimate. Those psychosocial changes may then have led to behavioral changes, such as exercising more frequently, participating more regularly in social activities, and closer and cross-generational relationships. And those behavioral changes may in turn have contributed positively to cognitive functioning.”

long lasting

That the subjects in 2011 – about seven years after the outbreak officially ended – had even better episodic memory suggests that the wake up call which Xu mentioned above, lasts a long time. It is unclear whether the Chinese subjects who were confronted with SARS between 2002 and 2004 still have a better cognitive function than the Chinese who were not directly confronted with SARS. Researchers are currently collecting data from later years to answer that question. “But if the SARS survivors have maintained their positive behavioral changes, you can expect the cognitive health benefits these have to hold. However, those benefits can gradually diminish, because cognitive decline in later life is simply insurmountable.”

Pandemic

The research of Xu and colleagues is not only interesting, but also very relevant. After all, we see ourselves once again being confronted with a coronavirus worldwide. Could this pandemic also have positive consequences for our cognitive functioning? Xu thinks so. In fact, perhaps this pandemic will encourage us to change course even more strongly and then benefit even more from it. “The SARS-CoV-2 pandemic has done far greater damage to almost every aspect of the global community than the SARS epidemic did. In theory I think the wake up call for those who have survived to date, is loud enough to put us on the trail of even greater behavioral changes and maintain them for much longer.”

And so this pandemic can also help improve our health – because we are becoming much more careful with it. “The main implication of our study is that a devastating epidemic can have a silver lining for those who survive it. But ultimately what matters is that survivors change their behavior positively in the aftermath of the epidemic and that they maintain those behavioral changes.”