Other diseases less common in a pandemic

Yes, there are also other pathogens than the coronavirus: Many of them were registered much less frequently in Germany last year. Why is it?

The last cold? More like a dark memory. And even the child, who is constantly ailing, is noticeably healthy for a long time. Such observations were made by some people during and after the lockdown last spring. At that time one could still ask oneself: is it just imagination? Perhaps because of concern about Corona, do you listen more to yourself or only now really appreciate freedom from symptoms?

2020 is now over and scientists have drawn their first conclusions. They seem to confirm the observations made in spring: "The number of cases of many other infectious diseases fell during the Covid 19 pandemic compared to previous years," said Sonia Boender from the Surveillance Department at the Robert Koch Institute (RKI) on request. The data converges there not only on Covid-19, but also on many other ailments.

Less respiratory and gastrointestinal diseases

In order to examine possible pandemic effects, the RKI experts carried out an analysis of relevant notifiable diseases, from tuberculosis to salmonellosis to hepatitis E. Between March and the beginning of August 2020, almost 140,000 such non-Covid-19 cases were reported. This corresponds to a decrease of 35 percent compared to the value that would have been expected based on the previous years (January 2016 to February 2020). Possible annual fluctuations and trends have been taken into account.

According to the analysis, respiratory and gastrointestinal diseases fell particularly sharply. Sexually transmitted infections decreased less sharply. From the point of view of experts, there isn't one reason for the numbers to fall. This is dependent on several factors, pathogen-specific and cannot be explained by data analysis alone, explained Boender.

But: The measures to contain the pandemic would certainly also have had an impact. School and daycare closings, home office, distance rules, contact restrictions and hand hygiene would have prevented in particular the person-to-person transmission of pathogens causing respiratory and gastrointestinal diseases.

RKI has fewer motion sicknesses

According to the RKI, the overall decrease affected all age groups and was most pronounced in children up to 14 years of age and seniors over 80. According to the evaluation, diseases such as chickenpox and whooping cough occurred less than half as often as expected during the study period. With measles, the minus is particularly large at 85 percent. The epidemiologist Rafael Mikolajczyk from the Martin Luther University Halle-Wittenberg explains that in the case of measles, however, he would look less for the effect in the corona restrictions. Strong fluctuations from year to year are common with measles. Even at the beginning of 2020, the numbers were low.

According to expert Boender, the fact that Germans who love to travel were less able to wander into the distance because of the pandemic is also noticeable: As a result, fewer diseases such as dengue fever and malaria have been observed, which are otherwise diagnosed in returnees, she said.

Regarding the number of reports, it must always be taken into account that these depend not only on the actual illnesses, but also, for example, on going to the doctor and on tests. Recorded cases therefore never show a complete picture. So could it be that the lower numbers are also related to the fear of some people of corona infections in waiting rooms, the strong Sars-CoV-2 focus in the health system and the overloading of the authorities?

Corona measures slowed the flu wave last spring

A deterioration in the recording due to other pollution in the pandemic is conceivable, says Rafael Mikolajczyk. "But I would ascribe less importance to this - and would also expect that the control measures have had effects on other infections." Like experts from the State Office for Health and Social Affairs in Berlin, he assumes that the measures, especially in the case of infectious diseases that are transmitted in the same way or similar to Sars-CoV-2, can be a reason for their decline.

As early as the spring of 2020, it had become apparent that the first lockdown of the flu wave brought an early end to it. According to the data available so far, colds and influenza are also rarer in autumn and winter 2020 than in previous years. The rate of acute respiratory diseases has been significantly lower since September than in the previous seasons, writes the Influenza Working Group at the RKI in the weekly report at the end of the year.

Not even 300 influenza cases confirmed in the laboratory have been reported nationwide since the beginning of the season in autumn, a year ago it was already more than 5000 at the time. In the metropolis of Berlin, only five influenza cases have been confirmed since October. "So far, it has been assumed that the circulation of influenza viruses will be at an extremely low level in the 2020/21 season," write the RKI experts. This coincides with observations abroad.

Increased cases of TBE brain infections

Not only registration data, but also the analysis of sick leave shows effects in the pandemic context. As the health insurance company AOK Nordost recently reported, the protective measures slowed down other infectious diseases from the end of September to mid-November 2020 in Berlin, Brandenburg and Mecklenburg-Western Pomerania. Sick leave has declined compared to the same period in the previous year, for example due to flu, gastrointestinal infections, pneumonia and acute bronchitis.

In the RKI analysis of the number of registrations from March onwards, there was an increase in only one of the diseases examined: TBE (early summer meningoencephalitis), which is transmitted by ticks. That too does not have to be solely related to the urge of many people to go into the green during lockdown times. There were warnings, for example from the Red Cross, that there were more ticks due to the mild winter and that the season had already started in March.