Seoul, Aug 18 (IANS): South Korea's disease control agency on Sunday said the level of the Covid-19 virus in wastewater has nearly doubled in just a week, following a surge in infections during the summer vacation season.

According to the Korea Wastewater Surveillance programme, run by the Korea Disease Control and Prevention Agency (KDCA), the average concentration of the virus at local sewage treatment plants reached 47,640 copies per millilitre during the second week of August, Yonhap news agency reported.

It sharply rose from the 24,602 copies per millilitre recorded the previous week.

The data is based on the levels of the Covid virus in water treated by 84 wastewater plants across the country.

The KDCA has used the method since April last year to assess the number of Covid patients within communities.

"The project aims to track the trend in the level of Covid-19 virus in wastewater, which has been rising recently," a KDCA official said.

Meanwhile, the number of newly hospitalised Covid-19 patients in South Korea reached 1,359 during the second week of August, increasing sharply from 878 a week earlier.

With the advent of the Omicron variety, the virus has become an extremely skilled spreader, it is not just a South Korean trend but a worldwide one.

Additionally, after their most recent infection or booster shot, people are more prone to contracting an infection again rather quickly. This is due to two factors: the virus's ongoing evolution, which enables it to infect humans despite having many layers of protection, and the fact that immunity to SARS-2 infections naturally waned over weeks and months.

Individuals with very mild cases may also not have a robust immune response, which means that when they re-expose to the virus, their bodies won't be as well-prepared.