The number of patients infected with Carbapenem-resistant Enterobacteriaceae (CRE), a super-bacterium that does not respond to antibiotics, has snowballed to surpass 10,000 patients as of Tuesday.

The number is alarming compared with last year when the number of infected people exceeded 10,000 in November.

According to the Korea Centers for Disease Control and Prevention (KCDC), the number of patients infected with CRE from January to August was 9,675, a 25 percent increase compared to 7,741 during the same period last year. If the trend continues, the KCDC estimates that the number of CRE infections this year will reach 11,954.

CRE is a representative super-bacterium that does not respond to almost all antibiotics, including carbapenem-class antibiotics.

As super-bacteria infections are becoming a social issue, the KCDC has designated CRE and vancomycin-resistant Staphylococcus aureus (VRSA) infections as the third-class infections since June 2017.

While the problem of super-bacteria infections continues to rise, treatments available are limited in Korea. Among the new antibiotics developed globally in the past five years, only two products are approved in Korea -- MSD's Zerbaxa (ingredient: ceftolozane/tazobactam) and Dong-A ST's Sivextro (tedizolid).

Both products are not used in hospitals, however.

Zerbaxa failed to get insurance coverage because it could not prove its cost-effectiveness during the government's economic assessment of reimbursement. The Health Insurance Review and Assessment Service said it recognized the clinical necessity of the drug but the high cost of the drug made the cost-effectiveness unclear. It costs about 300,000 won ($250.7) per month for a patient.

Sivextro was the only antibiotic that won insurance benefit in the past 10 years. However, its low price yielded a small profit. After winning insurance benefits in 2016, the company kept delaying the market release of the drug and finally gave up.