The World Health Organization will oversee a COVID-19 vaccination drive in war-torn Syria that is expected to start in April with the aim of inoculating 20% of the population by the end of 2021, it reported on Tuesday.

The announcement comes amid a sharp increase in infections in government-held parts of the country. State media said intensive care units in state hospitals in the capital Damascus are full and medical staff have been called to stay on alert to deal with coronavirus patients.

Among those infected earlier this month were Syrian President Bashar Al-Assad and his wife Asma who are now both in a “state of recovery,” according to the presidency.

WHO said it doesn’t know what variant or variants are spreading in Syria given that the country’s laboratory capacity is weak and it has sent samples to labs outside of Syria for more information. Neighboring countries have seen both the United Kingdom and South African variants.

The country that had a pre-war population of 23 million people has registered around 50,000 COVID-19 infections, of which 40% are in the last rebel stronghold in the Syria’s northwest along the border with Turkey, according to Akjemal Magtymova, WHO representative and head of mission in Syria.

Magtymova added that over 17,000 cases have been recorded in government-held parts of Syria, while in areas controlled by Kurdish-led U.S.-backed fighters there have been more than 9,000 cases.

“I do believe that the real numbers are much higher. The virus is not behaving differently in Syria,” said Magtymova about government-controlled areas. She spoke from the northern city of Aleppo during a virtual news conference.

Syria’s Health Ministry has registered nearly 17,600 cases, including 1,175 deaths, since the first case was recorded in March last year.

The WHO representative said the fatality ratio is highest in government areas, where out of every 100 people, 6.7 or 7 are likely to die. She also noted that the overall case fatality is 4.5 while in the northwest it is 3 and the northeast is 3.9.

There have been 411 deaths in the region, said Mahmoud Daher, the WHO representative responsible for northwest Syria, noting that there was a rise in cases between August and December.

He added that the “curve has gone sharply down” recently but cautioned that the region will probably see an impact of the third wave that is happening in other territories as well as across the border from Turkey.