Serotyping of Dengue Virus from Deadly Outbreaks of Pakistan

Abstract

Dengue Dengue virus (DENV) belonging to the family Flaviviridae consists of 4 serotypes (DEN-1, 2, 3 & 4) causing severe illnesses like dengue fever (DF), Dengue Hemorrhagic Fever (DHF) and Dengue Shock Syndrome (DSS). Dengue fever has become an emerging disease in Pakistan during the past 5-7 years with an increase in the number of cases every year since 2006. The current study aimed at identifying the serotypes of dengue virus involved in 2011 outbreak of Pakistan. Samples were collected from all provinces of Pakistan. Patients were confirmed in the hospital by antibody captured Enzyme linked immunosorbent assay (ELISA). These ELISA positive serum samples were inoculated on HeLa cell line to raise the viral titer of dengue virus and then RT-PCR was done for serotyping of dengue virus. Initially D1, D2 primers were tried for serotyping of dengue virus but poor results were obtained.Then serotype specific primers were designed having equal fragment length targeting NS1 gene. This approach was successful in serotyping of dengue virus from Pakistani population. On Real time RT-PCR, Dengue virus (DENV) was detected in 43.33% (n=26) patients out of 60 analyzed samples. Among 26 positive cases, 76.9% (n=20) were children and 23.1% (n=6) were adults and 46.1% (n=12) were male and 53.8 % (n=14) were females. ELISA results of 26 PCR positive cases show that 53.8% (n=14) were positive for IgM, 15.4 % (n=4) were positive for IgG and 30.8 % (n=8) were positive for both IgG and IgM. In this study DEN-2 was detected in 13.3% (n=8) patients, DEN-3 was detected in 16.67% (n=10) patients and DEN-2 & DEN-3 coinfection was detected in 13.3% (n=8) patients. We did not detected DEN-1 & DEN-4 in 2011 outbreak of Pakistan in 60 analyzed samples. By this study we can conclude that DEN-2 and DEN-3 were the main serotypes involved in 2011 outbreaks in Pakistan.

Epidemiological study of dengue fever in District Swabi, Khyber Pakhtunkhwa, Pakistan

“…Dengue viral disease has caused many outbreaks in Pakistan in 1994 to 2011.In Pakistan Dengue fever first time reported in 1982 in which out of 174 patients, 12 were the affected patients (Atif et al, 2016). The symptoms of dengue fever first time seen in 1994 in Karachi, while in Khyber Pakhtunkhwa the dengue fever case was initially registered in swat in August 2013, Dengue infection spread from one place to another through travellers.…”

Burden and distribution of dengue infection in Pakistan (2000-19): a review

“…The worst outbreak of dengue in KP (Swat) was reported in 2013 and then in the following years the infection rate decreased rapidly and might be due to awareness among people to deal with the mosquito vectors . In some areas the infection is spreading and may be it is due to increased population, urbanization, uncontrolled vector growth, traveling, unawareness, and failure of public health departments (Ahmed et al, 2013;Atif et al, 2016). Similar situations were faced by developed countries also like Germany (Murray et al, 2013).…”

“…Of the total dengue cases, 15124 were confirmed for dengue infection from multiple cities of the country including Islamabad, Rawalpindi, Lahore, Faisalabad, Peshawar, Karachi (Rafique et al, 2015(Rafique et al, , 2017Ali et al, 2016;Koo et al, 2013;Khan et al, 2010;Atif et al, 2016;Munir et al, 2014;Suleman et al, 2017a;Shahid et al, 2019;Zamir et al, 2012;Zafar et al, 2010Zafar et al, , 2013Bhatti et al, 2015), Azad Jammu and Kashmir (Tariq et al, 2006) and Swat (Ali et al, 2016).…”

“…While some reported all four serotypes from Lahore in 2008 (Javed et al, 2009;Humayoun et al, 2010). During 2011 all the four serotypes as well as mixed infections were reported from Punjab and KP (Ali et al, 2016) while some studies reported only II, III (Atif et al, 2016;Assir et al, 2014a;Idrees et al, 2012). The prevalent serotype in 2013 was DENV-II in the country (Shahid et al, 2019).…”

Effectiveness of Comprehensive Campaign for Dengue Control in Southern Punjab, Pakistan - An Experience of 2 Years

“…Life-long immunity is achieved by a particular serotype but temporary cross-immunity is attained to other types. 3 In 2006 Co-infection of DENV-2 and DENV-3 was identified while DENV-2, DENV-3 and DENV-4 co-circulation was determined during 2008 dengue outbreak in Lahore. 4 According to WHO, higher risk of dengue fever outbreaks in subcontinent is attributable to several factors including precipitation, moderate temperature, population density, and ineffective implementation of the dengue vaccine and poor attitudes toward dengue prevention among community.…”