New Delhi: While Kerala has succeeded in preventing the spread of COVID from expats returning to the state, it couldn’t adequately control the infection from other states, a genome sequencing study of the coronavirus that causes the disease has shown.
Two major genetic mutations in the virus in the state have had the ability to spread the disease rapidly, the research showed. Of the virus variants detected in Kerala, 89 have been reported for the first in India and four of them for the first time in the world.
The research was conducted jointly by Kozhikode Medical College, CSIR's Institute of Genomics and Integrative Biology and the Academy of Scientific and Innovative Research.
Manorama has obtained the results of the genome sequencing study done on 179 of the 200 samples recently collected at the Kozhikode Medical College. As the samples are from North Kerala, it cannot be seen as an assessment of the overall situation in the state.
Virus came from Maharashtra, Odisha, Karnataka
Genetic sequencing can help determine where the virus came from. There are three main types of viruses that have spread in Kerala - K1, K2 and K3.
K1: 40 (35.4%) of the sequenced genomes belong to this group. It came from Maharashtra between May 11 and July 22.
K2: 42 (37.1%). This came from Odisha between February 12 and May 16.
K3: 25 (22.1%). This came from Karnataka between March 3 and May 27.
In many states, including Delhi, where COVID has spread on a large scale, the virus came mostly from foreign countries.
Virus groups
There are 10 types of coronavirus prevalent in the world that cause COVID-19. In India, the I/A3I group is the most prevalent.
About 60–70% of those infected with coronavirus in the world have the European clade known as A2a. In India, too, A2a was found in about 60% of the people with COVID.
India has the highest number of infections by the I/A3I type in the world, which is why it is considered to be the dominant group in India.
In Kerala, COVID was first detected in a person who had come from Wuhan in China. This was caused by the Chinese type B. All the samples from the Kozhikode Medical College that were tested for the study had A2a type virus.
Changes needed in testing methods
Five of the genetic mutations found in the samples are likely to escape detection with the RT-PCR test. This means if a person is infected with these types of mutated virus, then the RT-PCR test will show a negative result. Therefore, there is a need for changing the testing methods, the research said.
COVIDSeq
COVIDSeq, a procedure developed by a US-based genomics company Ilumina, was used for the research. The system can sequence 1,500 samples in 24 hours.
