Nigeria is now experiencing a fourth COVID-19 wave, health authorities in the country have said, attributing it to the rise in Delta and Omicron variants infections.

The most populous African country has recorded a 500 percent increase in infections in the past two weeks, Ifedayo Adetifa, head of the Nigeria Center for Disease Control (NCDC), said in a statement on Tuesday.

"The country is now in a fourth COVID-19 wave," Adetifa said, noting as of Sunday, Nigeria had recorded 223,887 cases and 2,985 deaths in the 36 states and the federal capital territory.

Health authorities in the country are intensifying risk communication efforts to remind Nigerians of the risk and the need to take collective responsibility to reduce transmission of the virus, the senior public health official said.

"The response to COVID-19 requires a whole-of-society approach. Therefore, individuals, families, and institutions also need to play their part in protecting each other by ensuring adherence to COVID-19 public health and social measures," he added.