Chennai, March 31 : Tamil Nadu officials were on Tuesday busy tracing persons who had attended a congregation at Tablighi Jamaat's international headquarters Nizamuddin Markaz in southwest Delhi, pointing out that around 1,500 persons from the southern state had gone there. According to officials, five persons who had attended the Delhi congregation have so far tested positive in Tamil Nadu, where the total number of cases had gone up to 74 due to seven new cases overall. They also brought Erode district under strict monitoring as 24 persons from there have tested positive for coronavirus. The official maintained that the spike in corona positive cases was due to the fact that those affected had mingled with others and passed on the infection. Chief Minister K. Palaniswami on Tuesday announced extension in service on temporary contract basis for doctors, nurses and lab technicians set to retire on March 30. On Tuesday, the state announced that five persons who had travelled to Delhi's Nizamuddin area this month had tested positive. Health Minister C. Vijayabaskar said that seven new corona positive cases were reported in Tamil Nadu, with the total corona cases now rising to 74. Out of the seven new male patients, five (three form Villupuram, two from Madurai) had travel history to Delhi. Of the remaining two, one person is a co-worker of a COVID-19 patient and the other had travelled to Thiruvananthapuram in Kerala. Some foreign nationals from Thailand and Indonesia had also attended the conference and then visited Tamil Nadu. Two Thai nationals tested positive have been admitted to hospital. The health department officials are screening about 1,000 persons who have returned after attending the conference. "We have covered more than 500 persons who had attended the Delhi event. The exact number is yet to be known," a health official said. According to him, a sizeable number of persons who had attended the conference are from Erode and Coimbatore. Other places wherefrom Muslims had attended the event are Sivaganga, Thanjavur, Nagercoil, Kanyakumari and other places. With Erode district topping the state with 24 positive cases, the Tamil Nadu government is seriously implementing its containment plan under which an area with 7km radius from the house of a coronavirus patients is declared a containment zone. All the homes located within that radius will be surveyed and its residents screened. Suspected cases are stamped with quarantine warning on the back of their hands. "None of the persons who had attended the conference from Sivaganga has been found infected with coronarvirus," J. Jayakanthan, District Collector, told IANS. Meanwhile, Commissioner of Revenue Administration J. Radhakrishan appealed to those who had attended the Nizamuddin Markaz in Delhi to self-declare so that necessary tests could be done and necessary steps taken. Appeals have been made to family members of attendees to home quarantine themselves and register with the nearest government hospital. Officials in Vandavasi had enquired with 37 persons who had attended the Delhi conference. A 54-year-old person in Madurai tested positive for coronavirus and later died. It was learnt that he was in contact with two Thai nationals who were present at the Delhi congregation. A doctor who treated COVID-19 patients in Erode, her 10-month-old baby and two others in her household tested positive and are admitted to hospital. In 13 districts where coronavirus patients have been reported, about 1.08 lakh homes have been checked and over 3 lakh persons screened. A health official told IANS the screening had brought to the fore many asymptomatic persons which was worrisome. As of March 30, as many as 3,052 contacts of 50 coronavirus patients in Tamil Nadu have been traced. A total of 74,533 persons have been home quarantined. The state is also taking steps to tackle increased admissions of COVID-19 patients by augmenting bed capacity in hospitals and ordering masks, ventilators and other items. Chief Minister Palaniswami had said that orders have been placed to procure 1.1 crore masks, 25 lakh N-95 masks, 2,500 ventilators, 30,000 test kits and other medical items. /IANS