Arvind Kejriwal, chief minister of India's capital Delhi, has tested positive for Covid-19 — one day after he spoke at a political gathering in the northern state of Uttarakhand with thousands in attendance, according to CNN. "I have tested positive for Covid. Mild symptoms. Have isolated myself at home," Kejriwal wrote in a tweet Tuesday morning, urging those who came in contact with him to get tested and self-isolate. Kejriwal's positive test comes as India continues to see a surge in cases, prompting fears among the medical community of a potential third wave fueled by the highly transmissible Omicron variant. Upcoming elections: Five states, including India's most populous, Uttar Pradesh, are heading to the polls for state elections in early 2022. While campaigning has not officially begun, several politicians, including Prime Minister Narendra Modi, have held large political gatherings, speaking without masks as thousands gather in attendance. Social distancing and preventative measures such as mask-wearing are often absent in the crowds. Delhi reported 4,099 new Covid-19 cases on Monday, according to state health authorities. The Omicron variant was detected in 84% of the city's new cases over the last two days, according to its health minister. 4 million children vaccinated India vaccinated more than 4 million children ages 15 to 18 against Covid-19 on Monday after the government approved shots for the group last month in a bid to prevent a potential new wave of infections fueled by the highly transmissible Omicron variant. India's Prime Minister Narendra Modi praised the nation's vaccination drive, calling it an "important step forward" in protecting children against the virus. "Congrats to all my young friends between the age group of 15-18 who got vaccinated. Congrats to their parents as well. I would urge more youngsters to get vaccinated in the coming days!" Modi wrote on Twitter. India has been slow at issuing approval of vaccines for children, and the rollout of booster shots for adults. On December 25, Modi announced the start of limited shots of vaccines for children and booster shots for certain citizens. Booster shots will be available for those age 60 and over with pre-existing medical conditions, health care personnel, and frontline workers, from January 10. The vaccination drive comes as India continues to record a sharp increase in infections, adding to concerns about the possibility of a third wave. India reported 37,379 new Covid-19 cases on Tuesday, according to the Ministry of Health — the second consecutive day of more than 30,000 cases and the highest daily figure since September last year.