Health and Tech: Dengue cases on the rise, causing alarm

This significant jump in neighbouring States can quickly jump to Telangana

The dramatic rise in cases of dengue in different States in the last one week or so should be a matter of concern for public health officials and general public, who are already grappling with the infections of conjunctivitis.

With the monsoon becoming active, Odisha, New Delhi, Bengaluru, Assam, and several regions in Kerala have reported a significant jump in dengue positive infections, a trend that can quite quickly spread to other States, including Telangana.

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Immediately after the drop in Covid-19 infections, the health officials in Telangana, last year, had reported a surge in cases of dengue during the monsoon. Widespread incessant rains in the last fortnight have also created ideal conditions for mosquito breeding, which could trigger a new wave of dengue infections during this season.

How bad is it?

In the last one week, Bengaluru reported a 142 per cent rise in dengue positive infections, while New Delhi is already deep into its dengue season. The health authorities in New Delhi have reported a five-year high and the local administration has launched campaigns to curb rampant mosquito breeding.

For the past six months, Kerala is in the grip of dengue, with authorities reporting over 3,500 positive cases and nearly 10,000 suspected infections. Other States like Odisha and Maharashtra have also started to report fresh infections.

This year’s dengue is unique

In Hyderabad, over the years, there have been numerous instances of severe drop in platelet count among dengue positive patients. Platelets are small blood cells that are produced by bone marrow and the low platelet count due to dengue will impair the ability of the blood to clot.

Based on multiple reports, this year many States are reporting a very unique aspect related to dengue infection in patients. In addition to drop in platelet count, the doctors in cities like New Delhi and Bengaluru, are reporting a severe drop in White Blood Cells (WBC).

While platelets are responsible for blood clotting, the WBC are part of the body’s immune system. A drop in WBC count among dengue positive infections should be a matter of worry as it comprises the immune system, making patients susceptible to other diseases, after they recover from dengue.

Dengue virus in India has evolved

The fact that this year, the dengue infections are causing a drop in WBC count, in addition to the reduction in platelets, should not be a surprise. Over the years, there is ample evidence that the dengue virus has evolved in the country, especially in South India.

In April, the researchers from Indian Institute of Science (IISC), Bengaluru, published a study titled ‘Evolutionary Dynamics of Dengue Virus in India’, in the prestigious Plos Pathogens, suggesting that the dengue virus has evolved dramatically in the Indian subcontinent.

The IISC scientists, through their study, reported that dengue outbreaks are cyclical and happen every 3 to 4 years. There are four serotypes of dengue virus, including DENV-1, 2, 3 and DENV 4.

For over the last decade, DENV-1 and DENV-2 have been the dominant serotypes but DENV-4 has recently emerged as a major serotype in South India. “In summary, DENV-1 and DENV-3 were the dominating serotypes in India till 2012. Since then, DENV-2 became the dominant serotype in most regions in India and DENV-4 is establishing itself in South India,” the researchers said.