Record High Lyme Disease Cases Reported in Berlin Amid Favorable Tick Conditions
The number of Lyme disease infections in Berlin has reached an unprecedented level since the introduction of mandatory laboratory reporting in 2013. According to the Berlin State Office for Health and Social Affairs (Lageso), 1,406 cases were recorded up to mid-December, significantly exceeding previous annual figures. In recent years, Berlin typically reported between 700 and 800 cases annually, with the previous year already surpassing 1,000 cases for the first time.
Specialists attribute this sharp increase to a combination of environmental and climatic factors. The summer months experienced above-average rainfall, creating ideal conditions for ticks, which are the primary carriers of Borrelia bacteria responsible for Lyme disease. Moist environments support the survival and proliferation of ticks, while milder winters, influenced by ongoing climate change, further contribute to the growth of tick populations. In contrast, prolonged dry periods are less favorable for tick survival.
Berlin is not unique in facing this rise in Lyme disease cases, as the condition is prevalent throughout Germany. In some instances, infections may occur outside the city, but are reported in Berlin due to patients seeking local medical assistance. The complexity of Lyme disease transmission is influenced by several factors, including tick density, weather patterns, and human outdoor activities.
Alongside the surge in Lyme disease, Berlin has also observed a record number of tick-borne encephalitis (TBE) cases, with nine infections registered this year, compared to a previous average of three cases annually between 2020 and 2024. Both diseases underscore the importance of heightened public awareness and preventive measures during the peak tick activity season, which typically spans June to August.
Ticks are commonly found in forests, along woodland edges, grassy strips near forest paths, and in dense undergrowth. Urban environments such as gardens, parks, and meadows are also potential habitats. Not all ticks carry Borrelia bacteria; estimates suggest that around 20 percent of ticks in Germany are capable of transmitting Lyme disease. Direct human-to-human transmission is not possible.
To reduce the risk of infection, health authorities recommend wearing long clothing and using tick repellents when spending time in tick-prone areas. After outdoor activities, individuals should thoroughly inspect their bodies for ticks and immediately remove any found. Prompt removal of ticks can minimize the likelihood of disease transmission.
Experts continue to monitor the impact of climate change on tick populations and the spread of tick-borne diseases, though the full extent of these influences remains under investigation. Ongoing public health efforts focus on education, early detection, and preventive strategies to address the growing risk of Lyme disease and other tick-borne illnesses in Berlin and beyond.