NEW DELHI: Serotyping of samples that were positive for dengue in the national capital confirmed two strains of the dengue virus — Type I and Type II. While Type I causes classic dengue fever, Type II is tied to hemorrhagic fever with shock.

The identification of the Type II strain has caused concern. However, officials of the National Vector Borne Disease Control Programme (NVBDCP) have stated that there is no cause for alarm. An official stated that Type I causes milder symptoms and has been found to be predominant. A few samples have tested positive for Type II.

An NVBDCP official said the results were preliminary due to the small sample size and they intend to carry out more tests to understand the trend. Uttar Pradesh also has Type I and II strains of the dengue virus.

Dr Neeraj Nischal, additional professor of medicine at AIIMS, said that the type of strain of dengue virus which is circulating is crucial to prepare for a potential crisis. However, it is more important to prevent the spread of the disease by curbing the breeding of mosquitoes.

Aedes aegypti mosquito, which spreads the dengue virus, is a freshwater breeder. Three municipal corporations in Delhi have shown that peri-domestic containers, including vases, flowerpots, bird pots, tyres, fountain water, etc., are accountable for around 38% of the mosquito breeding sites. Other places where the mosquitoes breed include domestic water storage containers, desert coolers and overhead tanks.

Dr Nischal said that people must make sure that there was no stagnation of water in such places, adding that authorities should make the fight against dengue a social movement by means of public awareness, timely identification of high-risk zones and use of anti-larval spraying, besides other measures.

Latest data from the municipal corporations on mosquito-borne diseases in Delhi indicate that there were 158 confirmed cases of dengue on September 11. This is higher than the figure reported in the same period last year. 

Dr Vinay Aggarwal, chairman, Pushpanjali Medical Centre in east Delhi, said that there appear to be more cases of dengue than of COVID currently. At Lok Nayak Hospital, medical director Dr Suresh Kumar, stated that there has been a significant surge in cases of dengue. Dr Kumar mentioned that new admissions for COVID-19 have declined but there has been a surge in cases of febrile illness that are testing positive for dengue. 

Source: ET Healthworld