The systematic protection of persons at sea remains flawed. This problem has become even more acute during the Covid-19 pandemic when port closures have caused an unprecedented humanitarian crisis at sea. This article looks at the impact of port closures on the rights of persons at sea and considers how international law can protect those rights. While persons at sea are afforded significant rights protections in international law, the rights and duties of States often clash, with the result that persons at sea can find themselves in something of a legal vacuum. In order to address this problem, this article argues that the various rights and duties of States must be interpreted and applied in a way that fully recognises the rights of persons at sea.