Concurrent Infection with Plasmodium vivax and the Dengue and Chikungunya Viruses in a Paediatric Patient from New Delhi, India in 2016.

Dengue and chikungunya fevers are transmitted by the common mosquito vector Aedes and malaria by Anopheles. Concurrent infections are reported due to co-circulation of these pathogens, especially in endemic regions. We report a rare case of triple infection with 3 arthropod-borne pathogens (Plasmodium vivax and the dengue and chikungunya viruses) in a 3-year-old child from New Delhi, India, in August 2016. The viruses were identified by RT-PCR and the parasite by microscopy and antigen detection. The dengue virus serotype 3 sequence was clustered in the genotype III by the phylogenetic analysis. Mixed infection with multiple pathogens is a challenge for accurate diagnosis due to the overlapping clinical symptoms. The accurate and timely diagnosis of multiple pathogens in such cases is important for rapid and effective patient management.

Circulation of dengue virus serotypes in hyperendemic region of New Delhi, India during 2011-2017.

BACKGROUND: Dengue fever has become a hampering menace in New Delhi India, since the disease has become hyperendemic, due to circulation of multiple serotypes of dengue virus (DENV). This hyperendemicity poses a greater risk of secondary infections in human health system. This is a major issue which leads to apprehension amongst the researchers and health organizations and thus requires regular epidemiological surveillance. METHODS: We analyzed the prevalence and serotypic distribution of dengue fever cases reported from the Southern part of New Delhi during continued surveillance from 2011 to 2017. The blood samples for the investigation were obtained from the patients suspected with dengue fever attending the OPD at a local Health Centre. The data for 2011-2016 was already published from our laboratory. The samples collected during 2017 were serotyped and characterized in the present study. RESULTS: A total of 565 samples (59%) were positive for DENV of 958 samples tested by RT-PCR during 7 years (2011-2017). Our study has shown that most infections were caused by DENV-2 during 2011-2015. The data has shown occurrence of all four serotypes of DENV during 2015 and predominance of DENV-3 in 2016 and 2017. Further, predominant combination of DENV-1 and DENV-2 was found in most of the co-infections. To the best of our knowledge this is the first study showing the epidemiological trend of dengue fever in reference to the circulating DENV serotypes and co-infections from a hyperendemic region of New Delhi during 2011-2017. CONCLUSIONS: This hyperendemic pattern of DENV and instantaneous shift in circulation of its serotypes is likely pose a greater risk of secondary infections. Inclusion of comprehensive community and hospital surveillance of dengue fever will assist in formulation and implementation of effective control measures.

Circulation of single serotype of Dengue Virus (DENV-3) in New Delhi, India during 2016: A change in the epidemiological trend.

BACKGROUND: Dengue is a rapidly emerging arthropod borne viral infection affecting tropical and sub-tropical regions of the world. Dengue is an acute febrile illness but sometimes causes more fatal complications like dengue haemorrhagic fever (DHF) and dengue shock syndrome (DSS). Delhi, the capital of India has become hyper endemic for dengue virus because all the four serotypes are circulating here. METHODS: The present study describes the identification of dengue virus from clinical samples collected from the suspected dengue patients from New Delhi, India during 2016. The CprM region of Dengue virus genome was analyzed for phylogenetic, selection pressure and Shannon entropy analyses. RESULTS: The present study reports circulation of a single serotype (DENV-3) in New Delhi, during 2016. The phylogenetic analysis revealed that Indian subcontinent (genotype III) of DENV-3 was circulating in Delhi during this period. Neutral selection pressure in the analyzed region revealed relatively conserved nature of this part of the Dengue virus genome. Amino acid at 31 was positively selected and had high entropy value suggesting probability of variation at this position. CONCLUSIONS: The changing trend in circulation of dengue virus serotypes necessitates the continuous epidemiological surveillance for the dengue outbreaks in this region.

A clinical report on mixed infection of malaria, dengue and chikungunya from New Delhi, India.

Arthropod-borne infections like malaria, dengue and chikungunya fever are transmitted by mosquitoes. The present report describes an unusual case of mixed infection with malaria, dengue and chikungunya viruses in a 21 year old male patient from New Delhi, India during monsoon season of 2016. The malarial fever was diagnosed by thin slide microscopy and antigen test. Chikungunya virus IgM was detected in the sample by the card test. Dengue and chikungunya viruses were further confirmed by RT-PCR for CprM and E1 gene respectively. Phylogenetic analysis clustered the study dengue virus serotype 3 sequence in the genotype III. Thus, the mono infections can not be differentiated from concurrent infections on the basis of clinical symptoms, the appropriate laboratory diagnosis is essential for the accurate pathogen confirmation. Precise and appropriate identification of the multiple pathogens in such clinical cases will assist in the effective management of these arthropod mediated infections.