EMERGING INFECTION AND MULTI RESISTANT PATHOGEN

1. EMERGING INFECTION AND MULTI RESISTANT PATHOGEN " SALMONELLOSIS - A Review "

2. What is emerging infection? • An emerging infectious disease is an infectious disease whose incidence has increased in the past 20 years and threatens to increase in the near future. • This include diseases caused by a newly identified microorganism or newly identified strain of a known microorganism. • Some examples of emerging infections are Ebola virus , Lyme disease, Salmonellosis/Salmonella , Shigellosis/Shigella, Dengue Fever.

3. Multi Drug Resistance….. • Multi-drug resistant organisms are bacteria or virus that are resistant to a number of antibiotic. • It is a condition enabling a disease-causing organism to resist distinct drugs or chemicals of a wide variety of structure and function targeted at eradicating the organism. • Many different bacteria now exhibit multidrug resistance, including staphylococci, enterococci, gonococci, streptococci, salmonella, Mycobacterium tuberculosis.

4. Cause for Multi-Resistance?? • The increase in multi antimicrobial resistant has been associated with the wide spread use of antimicrobial agents in food production. • Multi-resistance organisms arise naturally by spontaneous mutation. • Over usage of antibiotics also leads to the resistance of bacteria towards antimicrobials. • When the genes for resistance are passed on from one bacteria to other, then the bacteria will acquire resistance towards antibiotics.

5. Image showing the formation of antibiotic resistance gene in bacteria • Efflux pumps are transport proteins involved in the extrusion of toxic substrates from within cells into the external environment. • Pumps may be specific for one substrate or may transport a range of structurally dissimilar compounds (including antibiotics); such pumps can be associated with multiple drug resistance (MDR)

6. Salmonella Species…. • The genus Salmonella contains over 2,000 sero-species and is one of the most important pathogens in the family Enterobacteriaceae. • Many types of salmonella species are responsible for salmonellosis, but S. typhimuriumand S. enteritidis are the two most commonly found. • Salmonella causes food borne disease since salmonella transmits through raw or contaminated food products.

7. “Salmonella Typhimurium” Image showing Salmonella Typhimurium

8. S.Typhimurium…… • Salmonella typhimurium is a leading cause of human gastroenteritis. • It is a Gram-negative , anaerobic bacteria of the family Enterobacteriaceae, usually motile with peritrichous ( flagella in all direction)flagella. • S. typhimurium, causes a wide range of infections in birds and mammals ranging from self limiting gastroenteritis to severe systemic paratyphoid diseases. • S. typhimurium acts along with S.enteritidis and cause disease in the environment.

9. Transmission of salmonella… • Salmonella infections are zoonotic. • Salmonella bacteria can be found in food products such as raw poultry, eggs, and beef, and sometimes on unwashed fruit. • The present situation with S. typhimurium is complicated by the presence of the organism inside the egg, in the yolk.

10. Effects!!!! • Initial symptoms are diarrhea, vomiting, fever and abdominal cramps. • If not treated initially it leads to nausea, loss of appetite and gastro intestinal infections. • If the salmonella enters the blood stream and circulates there, it leads to an infection called bacteremia.

11. Effects due to drug-resistance… • Chronic stage of salmonellosis leads to Reiter’s syndrome. • Reiter’s syndrome leads to reactive arthritis, eye irritation and urinary tract infection. • The symptoms of Reiter’s Syndrome usually occur between one and three weeks after the infection. • Arthritis may even lead to spondylitis, inflammation of the vertebrae in the spinal column.

12. Treatment??? • Persons with severe diarrhea require re-hydration, often with intravenous fluids. • If the infection spreads to the intestines, the infection can be treated with Antibiotics. • The antimicrobials most widely regarded as optimal for the treatment of salmonellosis in adults is the group of fluoroquinolones.

13. The earlier drugs chloramphenicol,ampicillin and amoxicillin and trimethoprim-sulfamethoxazole are occasionally used as alternatives.

14. Test for drug resistance….. (i) Agar Dilution Method: • This test is done using 80 salmonella strains got from chicken carcass and giblet samples. These isolated samples were serotyped with slide agglutination and then tested for resistance to 23 drugs. • Amikacin ,Amoxicillin and clavulanic acid, Ampicillin, Apramycin,Carbadox,Ceftiofur,Ceftriaxone,Cephalotin,Chloramphenicol,Ciprofloxacin,Florfenicol,Gentamicin,Kanamycin,Nalidixicacid,Neomycin,Nitrofurantoin,Spectinomycin,Streptomycin,Sulfisoxazole,Tetracycline,Tobramycin,Cotrimoxazole,Trimethopri.

15. (i) Method contd… Result: • Out of all the 80 strains all the strains were susceptible to Ciprofloxacin, Nalidixic acid, Ceftiofur, Ceftriaxone, Cephalotin, Amikacin, Apramycin, Gentamicin, Neomycin, Tobramycin and Kanamycin. • Fifty one strains were resistant to one or more antimicrobials i.e. 63.7% were multiple drug resistant. • Less than 21% were resistant to Carbadox, Trimethoprim and Cotrimoxazole

16. (ii) In vitro testing method.. • The activities of mecillinam and Ampicillin alone and in combination were evaluated in mice infected with the LT 2 strain of salmonella typhymurium. • Ampicillin in doses of >=0.03 mg and mecillinam in doses of >= 0.5 mg reduced mortality rates from 77% in saline treated controls to a range of 0-47% (P<0.05). • The same doses of antibiotics also extended the median times to death and lowered significantly the means of splenic bacterial counts.

17. (ii) Method contd… • When both drugs were combined in doses that were partially effective or sub inhibitory alone, no synergistic effects were observed. • These results showed that mecillinam and Ampicillin given alone were effective in treating S. typhymurium infection but that combinations of two drugs were not synergistic in controlling the course of infections.

18. About PCR Technique…. • In molecular biology, the polymerase chain reaction (PCR) is a technique to amplify a single or few copies of a piece of DNA across several orders of magnitude, generating thousands to millions of copies of a particular DNA sequence. • In the PCR procedure trace amounts of DNA can be quickly and repeatedly copied to produce a quantity sufficient to investigate using conventional laboratory methods. • The PCR technique enables early diagnosis of malignant diseases.

19. Image of PCR!!!!!

20. Diagnosis using PCR Technique… • Multiplex PCR assay for Salmonella detection has been developed. • Six sets of primers were designed to detect the major Salmonella serotypes and phage types in Spain. • The different amplification profiles obtained allowed us to detect Salmonella bacteria and to distinguish the clinically prevalent Salmonella enterica serotypes Enteritidis, Typhimurium. • Using this method, we could detect a specific band for DT104 and U302 phage types in Salmonella serotype Typhimurium.

21. Vaccination……. • Salmonella is resistant to antibiotics and not to vaccines. Hence vaccines can be taken to prevent salmonellosis. • A single-dose, oral salmonella typhi vaccine strain has been sought as a carrier or vector of cloned genes encoding protective antigens of other pathogens. • Such a hybrid vaccine, administered orally, would stimulate immune responses both at the mucosal surface and in the systemic compartment and would potentially provide protection against multiple pathogens.

23. Prevention!!! • Do not eat or drink foods containing raw eggs. • Should not drink unpasteurized milk or raw milk. • Under cooked meat or poultry shouldn’t be consumed, as this meat may carry bacteria. • Frequent and over consumption of antibiotics should be avoided so that resistance of the pathogen to the antibiotic can be controlled. • Food prepared for infants must be very hygienic and bottles must be sterilized before usage, since infants are easily prone to bacterialinfections.

24. Conclusion!!!! • Control of multi-drug resistant Salmonella typhimurium DT 104 requires reducing infection in food animals and lowering the risk of contamination at all stages in the food production chain. • It is required to create an awareness amoung the public about the multi resistant pathogen and complications due to these pathogens.