Louse-borne relapsing fever (Borrelia recurrentis) in asylum seekers from Eritrea, the Netherlands, July 2015

Two patients from Eritrea, recently arrived in the Netherlands, presented with fever and were investigated for malaria. Bloodfilms showed spirochetes but no blood parasites. Louse-borne relapsing fever caused by Borrelia recurrentis was diagnosed. Treatment was complicated by severe Jarisch-Herxheimer reactions in both patients. Physicians should be aware of the possibility of B. recurrentis infection in migrant populations who travel under crowded conditions, especially after passing through endemic areas such as Ethiopia and neighbouring countries. Borrelia recurrentis has for many centuries caused infections of often epidemic proportions known as relapsing fever. Since the infection is exclusively transmitted by body lice and humans are their only host, large scale outbreaks are only expected under circumstances conducive to louse infestation. We here report the first introduction of louse-borne relapsing fever into the Netherlands after World War II