SEOUL, June 18 -- Infections with the Middle East Respiratory Syndrome (MERS) abated in South Korea despite lingering concerns over a new wave of contagion caused by a viral exposure to high-risk patients.

Three more MERS infections were added Thursday, bringing the total contagion to 165 since the patient zero was discovered on May 20, according to the Ministry of Health and Welfare.

The MERS spread eased recently amid the ministry's expectations that the viral disease crisis may end before July. After peaking at 23 on June 8, the daily increase in MERS infection went down from 14 on June 11 to 13 on June 13 and five on June 15 and three on June 18.

Despite the roughly downward trend, concerns remained over the third wave of massive contagion as the corona virus was exposed to a group of high-risk patients with other illnesses.

The 165th patient, tested positive Thursday, had received the kidney dialysis treatment after showing symptoms of the viral disease. More than 100 patients were quarantined as they were treated together with patient 165 at the Gangdong Kyunghee University Medical Center in Seoul.

Beds and sets at the dialysis room are reportedly arranged close, raising possibility for a number of infection from the 165th patient. It takes about four hours to get the dialysis treatment, and patients with kidney failure are very vulnerable to the MERS virus.

The patient 165 contracted the virus from the 76th patient at the Kyunghee hospital's emergency room, bringing the total number infected at the hospital to two.

The first MERS infectee in the southeastern city of Daegu had contact at a public bathhouse with more than 260 people after developing symptoms, but almost half of the potential carriers have been traced yet.

The 141st patient had traveled to the southern resort island of Jeju a couple of days before the 42-year-old man was confirmed positive Saturday. He accompanied his father who visited the Samsung Medical Center, in which a super spreader infected about 80 people.

During the Jeju trip, the man reportedly stayed at a car for long due to his bad health conditions, indicating that his symptoms could have shown at the island.

Meanwhile, two nurses were included in the list of new cases, after a radiographer at Samsung Medical Center in Seoul was tested positive Wednesday.

Contagion to medical staffs boosted worries about further spread as they tend to more closely contact with many other patients under treatment.

Until now, five doctors and 11 nurses were infected with the MERS corona virus. Other medical staffs catching the virus numbered 14.

Five more patients were discharged from hospitals as they completely recovered after being infected, bringing the hospital discharge number to 25.

Three more deaths, including patients 31, 77 and 82, were added, raising the death toll to 23 and the fatality rate to 13.9 percent.

Before being infected, the 31st and 77th patients had already suffered from other illnesses, including tuberculosis, asthma and high blood pressure. The 82nd patient was an 82-year-old caregiver at a hospital, for whom old age may have contributed to her death.

Male patients accounted for 70 percent, or 16 people, of the total deaths. Those in their 60s took up 35 percent, or eight people, of the deaths, followed by 30 percent in their 70s, 17 percent in their 50s and 13 percent in their 80s.

More than 90 percent of the MERS deaths had other illnesses or was of old age, which had been categorized as high-risk patients.

Excluding the deaths and those discharged, 118 patients are under treatment. Among them, 17 people have been in unstable conditions.

The number of those quarantined was 6,729 on Thursday, up 221 from the previous day. It was a slower increase than a 992 growth on Wednesday. Those ordered to stay at home was 5,857, with the number quarantined at the government-designated hospitals being 872.

Those freed from quarantine totaled 4,492 Thursday, up 541 from the prior day.