TAIPEI (Taiwan News) — The Kaohsiung City Government on Thursday (Jan. 20) confirmed that a family of three in the southern city has been infected with COVID-19, without any obvious link to the outbreak concentrated in the north of the country.

Because one of the Kaohsiung cases, a four-year-old boy listed as Taiwan's case No. 18,155, attends a private kindergarten, 79 teachers and fellow pupils have been subjected to rapid COVID tests and taken to a quarantine hotel on a special bus, CNA reported.

The cluster was discovered when the boy visited a doctor, though his father had already developed a fever and cough. In the days before he sought medical care, the father apparently conducted repair work on two ships in Kaohsiung’s harbor. As a result, a medical team visited pier No. 34 at the port Thursday afternoon to test possible contacts, according to CNA.

Listed as case No. 18,156, the father, who is in his 50s, has received two BioNTech vaccine doses, while the mother, who is in her 30s, has received one BioNTech jab. The boy has not received any COVID shots, according to the report.

The city government advised its schools against organizing trips to areas of the country already affected by the virus. The recent local outbreak centers on Taoyuan, but related cases have also been discovered in other parts of north Taiwan, from Keelung to Hsinchu.