Leptospirosis is a reemerging zoonosis that occurs worldwide and is believed to be underdiagnosed because of challenging diagnostics and a wide clinical spectrum of disease [
1]. The incidence in Europe has recently been reported to be 0.13 per 100,000 inhabitants [
2]. Leptospirosis is caused by
Leptospira species, a group of spirochete bacteria [
3] with 29 described serogroups and more than 200 different
Leptospira serovars [
4].
Leptospira species infect mammals as well as fish, birds, and reptiles [
5]. Infected animals become reservoirs for the disease, and rodents constitute the most important reservoir [
6].
Leptospira species colonize the renal proximal tubules of their reservoir hosts and are excreted in the urine [
7,
8]. When
Leptospira are excreted into the environment, they are able to survive for several months in water [
9], which constitutes an important source of infection [
4]. Humans are usually infected by contact with urine-contaminated water [
10].
Leptospira enter the human body by penetration of damaged skin or via oral, genital, or conjunctival mucous membranes, and they are hematogenously disseminated afterward [
11]. Disease manifestations vary from mild or asymptomatic to severe illness with multiorgan failure [
12]. Patients with leptospirosis typically present with fever, headache, and myalgia [
11], but symptoms of any organ may be apparent [
10]. Severe forms include meningitis, pulmonary hemorrhage with respiratory failure, or Weil’s disease characterized by jaundice, bleeding, and renal failure [
11]. Leptospirosis may mimic other infectious diseases, such as influenza, viral hepatitis, brucellosis, infectious mononucleosis, malaria, or dengue, depending on the setting [
10], or even bacterial or viral meningitis [
13]. A recent review on leptospirosis meningitis revealed that almost all patients (N = 366 adults) presented with fever (98%), headache (94%), and neck stiffness (93%) [
13]. The authors of that review found that the patients’ median age was 33 years, that most were male, and that the majority were believed to have acquired the infection from their work environment, with others contracting it after contact with fresh water [
13]. There were no cases of transmission from pets. In this report, we describe a case of leptospirosis meningitis in a young, previously healthy woman who was most likely infected by her pet mouse.