Since the beginning of September, Kerala has been witnessing a surge in COVID-19 cases, especially in Thiruvananthapuram. There are many factors that contributed to this sudden rise: Onam celebrations, widespread political protests and the general easing of COVID-19 restrictions among the public. This has reflected on the state’s daily COVID-19 cases and the Test Positivity Rate (TPR), which currently stands at 13.76%, when the World Health Organisation’s recommended level is 5%.
Test Positivity Rate refers to the number of positive cases out of the total samples tested. During the initial stages of the pandemic, the Kerala government pulled out all stops to keep the TPR below 2%. When the number of COVID-19 cases via contact started rising in June, the TPR gradually rose to 2.66% in early July. By August, it fluctuated between 6% and 7%. By mid-September, Kerala’s TPR touched 11.4% and on September 29, it was at 13.93%. The overall average TPR of the state is 6.84 percent.
COVID-19 cases doubled in three weeks in August-September. For instance, on average, Kerala reported 55 cases daily between August 29 and September 5, while it recorded 111 cases every day between September 12 and 19.
“TPR gives us an idea on how and where to increase testing in the state,” says Dr Amar Fettle, state nodal officer for COVID-19. It also helps identify hotspots and clusters.
For example, the Thiruvananthapuram coastal belt, especially Poonthura, had a very high TPR in July-August (about 47.82%), turning it into a COVID-19 cluster. “As more people were tested, more positive cases were showing up from the village. This showed that the virus was spreading fast here,” Dr Amar said. To counter this, health officials increased testing in the region, identifying and isolating more infected persons, he added.
‘Kerala delayed peak but this was expected’
According to Dr Gopikumar P, state secretary of Indian Medical Association (IMA) Kerala, the rise in infections was inevitable in Kerala as the state had to reach its peak at some point. “Other cities or states, including Chennai, Mumbai and New Delhi, too, hit their peak in the early stages of the pandemic,” he pointed out.
Kerala’s public health machinery, on the other hand, was trying to delay this peak to ensure that its existing treatment infrastructure, including ICU beds, ventilators and oxygen masks, are not exhausted, noted Dr Gopikumar.
“The state was trying to ensure that infected persons had access to tertiary health care, a ventilator or an ICU bed. And so far, Kerala has succeeded in this and in keeping the death rates low,” Dr Gopikumar added.
According to data provided by the government, Kerala is one of the few states with a low mortality rate of 0.38%. Although, many health experts in the state argue that the number of COVID-19 related deaths could be higher.
Read: Kerala’s ambiguous reporting of COVID-19 deaths is concerning, say medical experts
The state’s medical infrastructure, too, with the current data available, is currently adequate to meet the recent surge in daily COVID-19 patients, which is between 7,000 and 8,000. The state is roping in private hospitals and freeing up more beds, which are reserved for non-COVID-19 patients for COVID-19 care.
Read: With daily COVID-19 cases being reported in thousands, Kerala starts Plan C
Moreover, epidemiologists say that once at least 40% of the population are infected, the number of cases will begin to drop owing to herd immunity. “Based on available data, more than 30% of Kerala’s population has already been infected by the coronavirus. If we go by this, then in the next two to three weeks, we should see a decline in cases,” said Dr Gopikumar.
What to do if your area has high TRP
If a region is declared a hotspot or cluster zone, it indicates that the TPR there could be high. Any resident of that region should get themselves tested, as there is a higher likelihood that he/she is infected or is susceptible to infection.
“In such cases, a person need not explain to a health worker or a lab technician the reason to get themselves tested. A person should be able to get a test even if he or she does not show symptoms and is not a primary contact, who does not have symptoms,” Dr Amar explained.
On the other hand, if an area shows a lower TPR, then testing need not be increased there.
How to reduce TPR
Increasing testing and isolation is the only solution to reducing TPR, Dr Gopikumar said.
The biggest success story of health workers reducing Test Positivity Rate comes from Dharavi in Maharashtra. Asia’s largest slum reported community spread of coronavirus with very high positive rates.
“The health officials amped up testing. In fact, almost all households in Dharavi were and infected persons were put in First-Line Treatment Centres or hospitals until they recovered. Within three to four weeks, the spread of the infection slowed down drastically in Dharavi,” Dr Gopikumar explained.
More testing would reveal undetected patients who can then be isolated from the non-infected persons. “Filtering out infected persons this way and isolating them, will then leave only non-infected persons in the community, effectively reducing the spread,” he added.
