Determination of Significant Baseline Widal Titre amongst Health Personnel & General Population of Ajmer City

Abstract

Background: Enteric Fever is the most infectious disease on global scale and endemic in all parts of India. In a developing country like India laboratory diagnosis of enteric fever relies heavily on serological tests such as widal test. Knowledge of prevalent endemic titre in a region needs to be periodically updated to interpret the significance of the titre as to patient is indeed suffering from enteric fever or not. The present study has been undertaken to evaluate the baseline antibody titre for O, H antigens of Salmonella Enterica, serovar Typhi and AH, BH antigen of Salmonella Enterica, serovar Paratyphi among health personnel and general adult population of Ajmer (Rajasthan). Aim and objectives: To evaluate the significant endemic baseline titre of Ajmer city using quantitative Widal test to suggest the cut off value for interpreting a positive widal test. To compare the endemic baseline titre amongst the Health care providers and General Population. Material and methods: A total number of 600 healthy volunteers and 200 medical personnel working in Jawahar Lal Nehru Medical College, Ajmer were screened during period of study from 1 st April 2014 to 31 st December 2015. Non repetitive samples were collected from healthy adults aged 18 year to 70 year. Results and conclusions: Out of 600 screened samples for healthy volunteers 61% were males and 39% were females. The frequency of positive results was 43.67%. The agglutinins to S. Typhi were the most prevalent among the sera of various dilutions (33.16% for 'O' antigen and 43.33% for 'H' antigen) which was tested. The levels of agglutinins for Salmonella paratyphi AH and paratyphi BH were low (only 1.16% for AH and 1.83% for BH antigen respectively).Out of 200 samples of health personnel screened 69% were males and 31% were females. The frequency of positive results was 45.5%. The agglutinins to S. Typhi were the most prevalent among the sera of various dilutions (33.16% for 'O' antigen and 44.5% for 'H' antigen) which were tested. The levels of agglutinins for Salmonella paratyphi AH and paratyphi BH were low (only 4.0% for AH and 1.5% for BH antigen respectively). Based on the above results, it has been recommended that cutoff titre of 1:80 for anti-O antibodies and of 1:120 for the anti-H antibodies may be considered as diagnostic for enteric fever in Ajmer region of Rajasthan, India.