Blood samples from typhoid fever suspected patients were collected.

Alltogethers 400 patients suspected of having typhoid fever were collected at Nepal Medical College (NMC). Different age group and sex visiting in Microbiology Laboraory for blood culture were included in the study from April to September 2017.Blood samples were collected aseptically. Samples collecting site were also make sterile with 70% alcohol.

Blood collection for paediatric patients was 3 ml and 5 ml for adults patients were collected and incubated into Brain Heart Infusion (BHI) broth at the ratio of d1:10. After incubation at 37℃ for 24 hours. After 24 hours of incubation, if there is seen turbidity in BHI broth, it was then sub culture into MacConkey agar, blood agar and chocolate agar respectively.4

Next day, if there was seen non lactose fermenter pale colour colonies then it was further confirmed bu using standard mocrobiological techniques. Such as biotyping e.g. colony morphology, staining reaction and biochemical characteristics and serotypng using specific atisera i.e. Denka Seiken Co. ltd., Tokyo, Japan. Likewise patients information such as patient name. age. Sex. Ward, bed no (if admitted), brief clinical history, duration of hospital stay and histroy of antibiotic use were taken.

Specimens were handled, processed and disposed by using standard guidelines for biohazardous materials. Spills was immediately disinfected.

A positive control and a negative control were included in each run.

The study subjects was suspected typhoid fever patients visiting in Nepal Medical College, jorpati. In this study, total 400 blood samples were proceed both from out patients and inpatients visiting in hospital. In this study, male population were more infected (60%) than female population (40%) (Table 1). Likewise, in total isolated cases (200) of Salmonella spp, Salmonella typhi (180) was more prevalent organism than Salmonella paratyphi A (Figure 1).

Nepal is a pocket area of typhoid endemic city due to cross contamination of food and drinking water with sewage and poor sanitation status. Estimation of the disese burden and its etiology would be helpful in the development of effective prevention and control intervention 5. Out of 200 cultures confired typhoid fever cases, 180 were caused by salmonella typhi and 20 were by Salmonella Para Typhi. Such a higher prevalence of typhi serovars in our study complies with the study by Adhikari et al, (64%) and (35.9%) of Salmonella and Salmonella respectively 6. In accordance to this study such a high prevalence of Salmonella Typhi was due to contaminated drinking water supply ia small Nepali town has recently been described 11. However Shirawa et al documented Salmonella Paratyphi are more prevalent serovar in Kathmandu, Nepal 7. Which is suppported by another study of Pramod et al., (35.9%). Salmonella and (64.1%) Salmonella Paratyphi 8. Although, there is no such well established cause of serovar vriation in tyhphoid cases. Higher incidence of Salmonella Typhi might be due to waterborne transmission of Salmonella Typhi as it usually involves smaller inocula than paratyphoid achieved through food borne transmission that require large inocula 9.

In accordance to this study, more prevalent rate of typhoid cases was in male than females 10. Which was done by Mohantyet al 2006 in All iIndia institute of Medical science. The one of the strong reason for such a high rate in males were that males in Nepal, at present also usually worked outside their homes and also eat street food and drinking water are liable to contaminated.