Israel’s Health Ministry on Monday issued new guidelines for COVID testing with antigen tests. The tests should be carried out three days after contact with a confirmed COVID carrier since it’s been found that earlier tests produce many false negatives. Additionally, users should first swab their throat and then their nostril (with the same swab), and not just their nostrils as the instructions say.

According to Dr. Nadav Sorek, the head of the epidemiology lab at Assuta Hospital in Ashdod, it’s also recommended to take repeated tests. “Repeated tests will succeed in detecting the virus since at some point the virus load will be high enough that an antigen test will be able to detect it,” he said. “So even if you receive a negative antigen test, there’s value in undergoing another test 24 hours later.”

A Channel 12 News report on Sunday said that the rapid antigen tests being used by Magen David Adom until just a few days ago were ten times less reliable in detecting Omicron than other antigen tests. After the Health Ministry informed MDA of the tests’ unreliability, they stopped using them but did not inform the public. The report added that the tests, the SD Biosensor and the BD brands, are still being sold.

דו״ח של המעבדה המרכזית לנגיפים קובע: מתוך 6 בדיקות אנטיגן שמשווקות בישראל, 2 הראו רגישות נמוכה פי עשרה בזיהוי האומיקרון. מד״א ביצעה בדיקות מוסדיות עם הסוג היעיל פחות. לפני 3 ימים שינו במד״א את סוג הבדיקות. את הציבור עדיין לא עדכנו בממצאים והבדיקות נמכרות כרגיל pic.twitter.com/HUUV3L7X92

— עמליה דואק (@AmalyaDuek) January 9, 2022

Health Ministry Director-General Nachman Ash on Monday urged Israelis who are experiencing symtoms such as a cough, sore throat or runny nose to remain at home even if their antigen tests are negative. Reports on Sunday said that nearly half (47%) of confirmed COVID cases are not detected by antigen tests.

(YWN Israel Desk – Jerusalem)