Serological Evidence of Rickettsial Infection by Weil-Felix Test in Tertiary Care Hospital in Bangladesh

Abstract

Introduction: Rickettsial infections are re-emerging diseases and are major causes of febrile illnesses throughout the Asia-Pacific region. It is difficult to diagnose due to the non-specific clinical manifestations, absence of reliable and affordable diagnostic tests thereby contributes to increasing the acute febrile burden and preventive illness in many populations. Undiagnosed or late-diagnosed cases are associated with high morbidity and mortality. Objectives: The study aimed to determine rickettsial disease by Weil-Felix test and to know the frequency of rickettsial diseases in febrile patients presenting to tertiary care hospitals in Dhaka, Bangladesh. Methods: In this study, a total of 135 peripheral blood samples were taken and tested by Weil Felix test from clinically suspected patients of rickettsial fever. Results: Weil- Felix test was positive in 33((24.4%) cases. Of Weil- Felix test-positive cases, OX-2 was positive in 87.87% cases, followed by OX-K (6.06%), OX-19 (3.03%), and both OX-2 & OX-K (3.03%) cases. OX-2 positive cases are suggestive of spotted fever group, OX-K of scrub typhus group, OX-19 of typhus group, and OX-2 & OX-K are suggestive of both spotted fever group and scrub typhus group. This finding suggests that most cases were infected with spotted fever group rickettsiae (SFGR). Conclusion: Analyzing the present study's findings, it may be concluded that rickettsial infection is not uncommon in Bangladesh. Weil-Felix test can be used in laboratories to diagnose rickettsial diseases where specific reliable serological or molecular test is not available.