Chikungunya in returning traveler to Germany

Acknowledgement
BEACON thanks the GeoSentinel Site at the Institute for Tropical Medicine, LMU University Hospital, Munich, Germany, for this submission.

Key findings
A confirmed case of chikungunya virus (CHIKV) infection in an adult German traveler returning from Mogadishu, Somalia, highlights the importance of clinician vigilance for such cases coming from the Horn of Africa.

Case description

• An adult patient presented with symptoms of fever and generalized arthralgias after returning from a visit to friends and relatives (VFR) in Mogadishu, Somalia, where the patient had stayed from late June to late July 2025.
• The patient developed a fever, severe polyarthralgia, and nausea on the evening of their return to Germany and sought care two days after symptoms began.
• The patient complained of generalized arthralgias and nausea, and on examination, was febrile (38°C) but showed no rash. Joints were not swollen but tender to palpation.

Laboratory results

• Leukocytopenia: L 2.3 G/L (normal: 4–10 G/L)
• Thrombocytopenia: PLT 128 G/L (normal: 140–360 G/L)
• CRP 43 mg/L (normal: <5 mg/L)
• Dengue NS1 antigen, malaria thick and thin blood smears, and malaria rapid diagnostic test (RDT) were negative.
• Chikungunya virus polymerase chain reaction (PCR) was positive.

Epidemiological analysis

• The patient reported that many people in Mogadishu were experiencing similar symptoms, including fever and joint pain, indicating possible community spread of CHIKV in the area.
• This case highlights the importance of considering CHIKV in febrile travelers returning from Somalia and other areas of Africa.
• Further epidemiological investigations may be needed. Additionally, viremic travelers returning to Europe and other regions where Aedes mosquitoes are common during summer should be advised to use repellents to prevent local transmission of arboviral diseases.

Comparative and future outlook

• On 22 Jul 2025, the WHO raised an alarm about the regional spread and global importation of chikungunya cases, following a large outbreak across the Indian Ocean islands that already affected up to one-third of the population. WHO has reported that the virus is now spreading to countries like Madagascar, Somalia, and Kenya, with epidemic transmission in Southeast Asia, including India.
• CHIKV is transmitted by Aedes aegypti and Ae. albopictus mosquitoes. Per the ECDC, Ae. albopictus is known to be established in many EU/EEA countries, including large parts of Germany, which raises the potential for local transmission as the number of imported cases in returning travelers increases.