Major aetiologies of acute undifferentiated fever in 2013 and 2014: an experience in retrospect

Abstract

Background: Major aetiologies of acute undifferentiated fever (AUF) show wide variations, especially in developing countries including India. A better understanding of ‘AUF causes’ helps in better management of such cases with attendant reduction in morbidity and mortality. The present analytical study, retrospective in nature, estimates burden of the AUF in the years 2013 and 2014 with some useful information and conclusions.Methods: Important pathogens ‘investigated for’ either as a ‘direct or indirect evidence’ included - Malaria parasite, Dengue virus, Salmonella typhi and paratyphi A and Chikungunya virus. Malaria testing included examination of peripheral blood smear with Giemsa stain and also immuno-chromatographic test to detect lactate dehydrogenase (LDH) for Plasmodium falciparum and Plasmodium vivax and also HRP2 for detection of Plasmodium falciparum infections. For dengue and chikungunya virus infections - specific IgM antibodies - were detected by ELISA test. Enteric fever was diagnosed by detecting IgM and IgG antibodies using enzyme immunoassay. For Widal test, agglutinating antibodies against the O and H antigens of S. typhi and “H” antigens of ‘S. paratyphi A’ were undertaken. All the test procedures, including sample collections, were performed as per manufacturer’s recommendations, and, as per ‘standard operating procedures (SOPs)’.Results: Of the 10,670 samples received for dengue investigations, 3646 i.e. 34.17% tested seropositive for dengue cases. Percentage seropositivity for chikungunya was 18.6 (8/48). For dengue, 1193 (43.92%) and 488/577 (84.57%) samples were positive in the year 2013 and 2014 respectively in Delhi alone. Annual peak in months of September to November was observed for dengue while a bi-annual pattern was observed for malaria with two peaks occurring in months of May-June and August-September respectively for the year (s) i.e. 2013 and 2014. Enteric fever was present throughout the year with no specific distribution pattern. Majority of patients were from Delhi and adjoining Haryana followed by Western Uttar Pradesh. Co-infection of dengue with enteric fever was observed in only four cases.Conclusions: Dengue, chikungunya, malaria and enteric fever were the most important major causes of AUF in the year 2013 and 2014. Improved interactions with clinician counterparts generating awareness about major aetiologies of AUF would help in timely detection of such illnesses and hence better management reducing morbidity and mortality in the long run.