What is the fine-grained topic of the following text: To mark this year’s International Migrants Day, the International Organization for Migration (IOM) is calling on the international community to come together and remember the refugees and migrants who have lost their lives or have disappeared while trying to reach safe harbor after arduous journeys across seas and deserts. Only return the topic.
International Migrants Day and the International Organization for Migration's call for remembrance of lost or disappeared refugees and migrants