On December 31, 2019 a regional cluster of cases of pneumonia was reported in Wuhan in China probably deriving from a novel coronavirus, now acknowledged as SARS-CoV-2. The speed of the virus transmission resulted in a statement of the WHO on March 11, 2020 that Corona Virus disease (COVID-19) can be characterized as a pandemic . The first case in Germany was published on January 27, 2020. Particularly in the community of otolaryngologists, there was a rapidly growing awareness of the high risk of virus transmission during diagnostic and therapeutic procedures . This resulted in publication of recommendations and guidelines for clinical and endoscopic examination, surgical procedures and personal protection equipment of various societies in Germany. Ongoing political discussions resulted in an appeal of the German Health Minister to postpone elective medical treatments (March 16th until May 1st 2020), accompanied by national lockdowns (March until May 2020; December 2020 until May 2021), introduction of social distancing, use of face masks and hand washing (June 2020). Schools, kindergartens and public indoor premises were closed, and daycare was recommended to be arranged at home. Gatherings were limited to two persons, and avoiding traveling was recommended. The various measurements resulted not only in a decreased number of COVID-cases but also in a reduction in the number of airway infections in general  and particularly in children .
This is strongly confirmed by the findings of our study revealing a significantly reduced number doctor contacts with antibiotic prescriptions, particularly in the second quarter (Table 3; Fig. 2). Interestingly, this phenomenon affected strongly young male and female patients (< 20 years of age) in the second and fourth quarter. We have no scientific explanation for this age-related phenomenon. It should be emphasized that children under the age of six still do not have to wear face masks in Germany and the protective value of face masks appears questionable in children and adolescents either due to inadequate fittings of the masks or discontinuous utilization in peer groups. Fewer doctor contacts resulted at least in part by the fact that patients or parents did not present their children or adolescents in fear of infection. The introduction of getting a sick leave by phone call on March 9, 2020 to avoid doctor contacts (ended on May 31, 2020 but was later resumed October 19, 2020) is a likely contributing factor. However, our study provides sound information concerning antibiotic prescriptions which requires a physician who needs to be contacted. Thus, we assume that there was a true reduction in the number of sore throat patients. Fewer doctor contacts without antibiotic prescriptions in the fourth quarter can hardly be explained as having resulted from a lockdown, since the second lockdown started by December 16, 2020 (Table 3). Our findings favorably compare with the results of a recent publication  analysing contacts of otolaryngologists and pediatricians over time. There was a stronger compensation in the subgroup of pediatricians after each lockdown had ended compared to otolaryngologists.
The decrease of tonsil surgery in Germany in the last decades continued during the pandemic overall but was emphasised sharply by the aforementioned political appeal. These restrictions resulted in a huge decrease in the incidence of tonsil surgery up to 82%. While specialists in German Hospitals had to re-organize operation lists and their professional environment, social distancing in the general population had become one of the main tasks, included fewer doctor contacts. This by itself resulted in fewer referrals from primary care physicians to the hospitals. However, social distancing in its entire dimensions obviously contributed to fewer infections resulting in sore throat.
Our study reveals that most cases in tonsil surgery were indicated to resolve chronic tonsillitis followed by upper airway obstruction due to tonsil hypertrophy. It is noteworthy that none of the different surgical interventions ever reached the quantitative level of pre-COVID time period. Instead our study shows—adjusting for seasonality—a significant level shift in surgical cases before and after the restriction period. Depending on type of surgery case numbers reduced from 18 to 39%.
One of the most surprising findings of our study was the fact that the total number of patients presenting with PTA requiring surgical interventions such as ABTE and ID had decreased, too, sharply with the introduction of the first lockdown and remained stable on a lower level compared to the pre-pandemic episode. Since the design of our study is unable to clarify causal factors for this phenomenon, it can only be speculated that this may have resulted mainly from social distancing .
Our study reveals that the number of surgical interventions to resolve upper airway obstruction due to TH had decreased. While the origin of TH is currently not fully understood,  we have no explanation how the lockdowns might have contributed to this finding. However, since there was no compensatory increase in this indication for surgery there must have been a spontaneous resolution taken place.
Haapanen et al. reported a decrease in the total number of tonsil surgery in 2020 by 37.3% based on rather small pediatric patient population (n = 568 vs. 106.526 of our study) in Finland . The findings compare well to our study (− 34.0%) concerning elective surgery but our update for the first 5 months of the year 2021 revealed a stronger effect (− 54.5%). Emergency operations like in our study were not studied. Waiting times were not retrievable from the database of our study but had doubled in Finland for tonsil surgery.
Carrè et al. from France reported a number of only 350 emergency cases in 2020 compared to pre-COVID years in a tertiary pediatric emergency center (− 54%) including only one case with PTA . The authors stated that there was a 54% drop in consultations, which is hardly comparable with the reduction of doctor contacts in primary care.
Heward et al. from the UK investigated the clinical courses of 44 pediatric patients during the lockdown period and identified a significant reduction in the number of episodes of acute tonsillitis and antibiotic treatment  which is confirmed by the findings of our study. The authors stated that 70% of parents wanted to proceed with their child’s TE during the coronavirus outbreak which demonstrates the impact tonsillitis has on the child and their family .
Gelardi et al. from Italy investigated the clinical courses in 162 children by telephone interviews two months after the first lockdown had started . The parents reported a significant improvement of various symptoms resulting from tonsillitis or upper airway obstruction due to AD and/or TH. Grossly, the findings are confirmed by our study including a decrease of PTA since our patient population was not limited by age.
Smith from the UK reported changes in practice during the peak of the pandemic for the management of tonsillitis and PTA to avoid hospital admissions including iv-administration of cortisone and antibiotics . Fewer patients (n = 1.181) had presented to 83 emergency departments with acute tonsillitis or PTA which complies with the findings of our study.
In the study of Li et al. from the UK, no difference was identified in antibiotic prescribing behavior comparing face-to-face and remote consultations . The multicenter observational study was carried out in five general practice surgeries in North West Wales and encompassed 170 patients presenting with sore throat. Surprisingly, score systems like FeverPain or Centor-Score were rarely used (10% remote vs. 0% F2F). The findings support the idea that the findings of our study are unlikely to be biased by remote consultations.
Our study is not capable to estimate by which extent the decrease in the number of elective surgical cases was influenced by the financial compensation according to the Hospital Relief Act . However, the assumption is challenged by the simultaneous decrease of ABTE and ID to resolve PTA and needs further research. The underlying trigger for the decreases is likely multifactorial.