Level of Immunity, Neutralization of the COVID-19 Virus and Reinfections in Residents of 2 Migrant Workers' Residences

A previous seroprevalence survey showed very high seroprevalence levels among residents of the two among the residents of the two migrant workers' hostels surveyed, indicating a high level of circulation of the virus SARS-COV-2 during the 1st wave of COVID-19. The constitution of a cohort after the event would be an opportunity to obtain opportunity to obtain answers to crucial questions: duration of immunity, potential reinfections potential reinfections, potential re-clustering. Going back to check the serological status seems feasible, especiallyespecially in the Foyers de Travailleurs Migrants (high probability of finding the participants). There is an obvious scientific interest around the duration of immunity and reinfections in a population highly exposed during the first wave. Several articles document the decline of IgG antibodies in the months following an infection, but very few infection, but very few evaluate the protective character in the medium term (\>=6 months), especially in asymptomatic individuals. We are also concerned about the circulation of We are also concerned about the circulation of new variants and the immunity acquired after infection in residents. To date, no study on the duration of immunity has been conducted in migrant worker's residences.