Mobile vaccine carrier with a passive cooling system comprising: a housing having a lid notably hinged to a base member, so that the lid can be moved between a closed position and an open position; a vaccine storage member disposed within the housing and defining a storage space for a plurality of vaccine containers; and at least one cooling element disposed within the housing; the vaccine storage member further comprising: an inner container defining the storage space and having an inlet opening for placing and removing vaccine containers; a removable vaccine container holder for temporarily storing vaccine containers; and a cover member disposed on the lid, wherein the vaccine container holder comprises an abutment portion abutting against an outer portion of the inner container so that the inlet opening is covered by the vaccine container holder; and wherein at least a part of the cover member protrudes into the storage space when the lid is in the closed position; wherein the vaccine carrier further comprises a measuring device for monitoring the temperature within the storage space; wherein the measuring device has a sensor arrangement comprising a temperature sensor for monitoring the temperature in the storage space; wherein the sensor arrangement is supported on the cover member and wherein the temperature sensor is disposed within the vaccine storage member when the lid is in the closed position; and wherein the cover member comprises an elongated member with the temperature sensor being supported on an end portion of the elongated member, characterized in that the elongated member is integrally formed with the cover member. a housing having a lid notably hinged to a base member, so that the lid can be moved between a closed position and an open position; a vaccine storage member disposed within the housing and defining a storage space for a plurality of vaccine containers; and at least one cooling element disposed within the housing; the vaccine storage member further comprising: an inner container defining the storage space and having an inlet opening for placing and removing vaccine containers; a removable vaccine container holder for temporarily storing vaccine containers; and a cover member disposed on the lid, an inner container defining the storage space and having an inlet opening for placing and removing vaccine containers; a removable vaccine container holder for temporarily storing vaccine containers; and a cover member disposed on the lid, wherein the vaccine container holder comprises an abutment portion abutting against an outer portion of the inner container so that the inlet opening is covered by the vaccine container holder; and wherein at least a part of the cover member protrudes into the storage space when the lid is in the closed position; wherein the vaccine carrier further comprises a measuring device for monitoring the temperature within the storage space; wherein the measuring device has a sensor arrangement comprising a temperature sensor for monitoring the temperature in the storage space; wherein the sensor arrangement is supported on the cover member and wherein the temperature sensor is disposed within the vaccine storage member when the lid is in the closed position; and wherein the cover member comprises an elongated member with the temperature sensor being supported on an end portion of the elongated member, characterized in that the elongated member is integrally formed with the cover member.