RIYADH — Saudi Arabia"s National Scientific Committee for Infectious Diseases has given its approval for using different COVID-19 vaccines for the first and second dose, the Ministry of Health said in a statement on its Twitter account on Wednesday. "The approval is in accordance with international scientific studies that showed the possibility of giving two doses of two different coronavirus vaccines safely and effectively in fighting the virus, with the effectiveness of which the second dose aims to achieve," the statement added. In another statement, the ministry said that all those, who are 50 years and above (according to Hijri calendar) and have spent 42 days after receiving the first dose, can take the second dose, beginning on Thursday.