In a recent study, it was suggested that unvaccinated people are unlikely to develop an immune response against other variants of the coronavirus after the omicron infection. The antibodies induced by the Omicron BA.1 and BA.2 do not neutralize other variants unlike the antibodies induced by Covid 19 vaccine or SARS-CoV-2 variant. 

According to a report posted on Research Square, people getting infected with the omicron variant after the administration of three doses of the mRNA vaccine have higher levels of neutralizing antibodies against the two variants. While the antibodies were reported to be less efficient against the SARS-CoV-2 infection. However, in the case of unvaccinated individuals antibodies produced after infection was more specific to the respective variant and no antibodies were found against non-omicron virus strains stated Karin Stiasny and Judity Aberle of the Medical University of Vienna, Austria. They added that the BA.2 induced antibodies are particularly monotonous and don’t provide protection against any other variant. The study proves the importance of booster doses for immune protection. (Source: https://www.reuters.com/business/healthcare-pharmaceuticals/omicron-infection-induces-limited-immune-response-unvaccinated-covid-hospital-2022-04-18/ )