Allergies are the result of a hypersensitive immune system. The allergic immune system misidentifies an otherwise innocuous substance as harmful, and then attacks the substance with a ferocity far greater than required.
Laying off an employee is different from firing an employee. Firing means letting a worker go for any reason, whereas a layoff refers to an employment termination based on economics, usually involving more than one worker.
Talk to an Employment Lawyer. Generally speaking, no law prohibits employers from laying off workers. Unless an employee has a contract that limits the employer's right to fire, an employer is free to lay off employees as the needs of the business dictate. Employers may not discriminate in deciding which workers to lay off (by getting rid of mostly female employees or older workers, for example).