Sonova, the world's biggest hearing aid maker, said on Monday it would close some stores and cut jobs as it expects its first-half results to only partially recover from the effects from the COVID-19 pandemic.

The pandemic hit hearing aid makers worldwide as many of their customers are over 70 and have been isolating at home to avoid catching COVID-19, the flu-like infection caused by the virus.

The Swiss company said it expects first-half sales to drop 25-35% with single-digit earnings before interest, taxes and amortization (EBITA) margin at constant exchange rates.

Sonova added it remains cautious about a recovery in the second half of the year due to a rise in infections in several markets and the impact of recession on overall demand.

Research and development activities will continue according to plan, the company said.

(Reporting by Zuzanna Szymanska in Gdansk; Editing by Shri Navaratnam and Kim Coghill)