Shift in dengue transmission pattern

The current dengue epidemic was associated with a shift in the transmission pattern of dengue serotypes in favour of DEN-1, states Asiri Centre for Genomic Medicine, Asiri Surgical Hospital in a press release.

The trend has become clearer with the number of tests performed increasing in the past two weeks. Usually it is DEN-2 and DEN-3 that are found in Sri Lanka. So most people have immunity to DEN-2 and DEN-3. They do not have immunity to DEN-1.

As a result an increase in the transmission of DEN-1 would result in more people than usual developing the condition. This may be one reason for the current epidemic. We are also noticing another feature of this epidemic, i.e. mix infection with DEN-1 and DEN-3. 37.5 percent of patients positive for dengue in the past two months had mix infection with DEN-1 and DEN-3.

Before May we have not detected any cases of mixed infection. This may be one reason for the high number of deaths experienced in the current epidemic.

“We are happy to note that after we provided this information the Epidemiology Unit of the Ministry of Health has now set up a Dengue Laboratory network to collect and compare information, release said.