After marginal increase in COVID-19 cases in Telangana for two days, the number of positive cases detected in a day is on the decline again.
Despite comparatively high number of tests, less COVID-19 cases were detected from December 1.
However, experts suggested to use sero surveillance, and sewage surveillance, to ascertain if the virus is declining, or if it is the same as earlier months.
Facts speak
Comparison of the data from September will help to know the declining trend in numbers mentioned in media bulletin issued by the State Health department.
In September, when 51,000 to around 60,000 people were examined in a day, over 2,000 were diagnosed with coronavirus. From December 1 to 16, 48,000 to around 56,000 samples were examined in a day, and barring December 7 and 8, the daily cases did not cross 650. On December 7 and 8, 682 and 721 positive cases were identified, which is a marginal increase compared to other days of the ongoing month. Thereafter, cases started to decline again.
However, experts said that method adopted to test the samples is important. The State Health department uses Rapid Antigen Tests (RAT) and RT-PCR to detect coronavirus. However, the break-up of tests between the two methods is not mentioned in the media bulletin.
Director of CSIR-Centre for Cellular and Molecular Biology (CCMB) Rakesh Mishra had earlier said that since sensitivity or Rapid Antigen Test (RAT) is low (50% to 60%) compared to RT-PCR, we may not detect all cases using RAT.
Sero surveillance can be used to ascertain if the cases are on decline, or, if the situation is otherwise. In sero surveillance, antibodies against the virus present in a particular number of people are the measures to estimate the prevalence. The CCMB director also suggested sewage surveillance to know the prevalence.
