The Israeli Ministry of Health reported a Covid-19 outbreak in two schools in the town of Binyamina, 60 km north of Tel Aviv, which has infected 45 students.
The outbreak concerns a primary school and a middle school, Xinhua news agency quoted the Ministry as saying on Saturday.
An extensive testing operation, which began after one of the middle school students had been tested positive, revealed the outbreak.
According to the Ministry, the source of the outbreak is related to a family who recently returned from abroad and had tested positive for the Delta Covid variant.
On June 6, Israel started vaccinating teenagers aged between 12 and 15 against Covid-19.
Before that, only people aged 16 and over were eligible to get vaccinated.
The number of people vaccinated against Covid-19 in Israel currently stands at about 5.49 million, or 58.9 per cent of its total population.
Israel has so far reported 839,829 coronavirus cases.
The death toll from the virus remained at 6,427, while the number of patients in a serious condition decreased from 23 to 22, out of 47 patients currently hospitalised.