The number of COVID-19 related deaths in Africa has spiked as the continent grapples with local transmission of highly contagious strains of the virus, the World Health Organization (WHO) said on Thursday.

Matshidiso Moeti, WHO Regional Director for Africa, said the death toll from the pandemic increased by 40 percent in January, fuelled by a second wave of infections and new variants that have overwhelmed the continent's public health systems.

"The increasing deaths from COVID-19 we are seeing are tragic, but are also disturbing warning signs that health workers and health systems in Africa are dangerously overstretched," Moeti said in a statement issued in Nairobi.

She said that the death toll linked to the pandemic is expected to hit 100,000 by Sunday as the continent marks one year since the first positive case was confirmed in Egypt.

"This grim milestone must refocus everyone on stamping out the virus," said Moeti, adding that flattening the curve in Africa will take longer amid low vaccination rates combined with the emergence of new variants.

Statistics from WHO indicate that over 22,300 COVID-19 deaths were reported in Africa in the last 28 days, compared to nearly 16,000 in the previous 28 days.

The continent's fatality rate rose to 3.7 percent during the last 28 days compared to 2.4 percent in the previous 28 days and has so far surpassed the global average.

Moeti said that 32 African countries reported a rise in deaths in the last 28 days while 21 reported flat or declining rates, adding that the second wave that began in October 2020 and peaked in January is behind the spike in mortality.

She said that a survey from 21 countries conducted by WHO indicates that 66 percent reported inadequate critical care capacity while 24 percent reported burnout among health workers, hence worsening the risk of death from COVID-19.

Moeti said that 15 countries reported that oxygen production that is crucial to avert death of severely ill COVID-19 patients, was insufficient as they battled the second wave.

She said that a new variant that was first reported in South Africa has been detected in eight African countries, adding that speedy roll-out of vaccines is key to tame infection and fatalities.

"While a vaccine that protects against all forms of COVID-19 is our biggest hope, preventing severe cases which overwhelm hospitals is crucial," said Moeti.

"If cases remain mostly mild and moderate and do not require critical care, then we can save many lives," she added.