ABSTRACT
Purpose: This study was designed to evaluate the immunogenicity of hepatitis B vaccine in infants of rural and urban Pakistan and to find out the vaccine efficacy. Methods: A sample of 400 subjects was taken by simple random method from the rural and urban areas (200 from Rural and 200 from urban areas) of Rawalpindi District Pakistan. The serum samples were analyzed by Enzyme Linked Immunosorbant assay (ELISA) for the quantitative determination of antiHBs antibodies. Results: As 88 (22%) infants out of the total 400 were found to be seropositive at baseline. The post vaccination results showed that about 15 (7.53%) of infants had inadequate levels of antibodies (i.e. <10 IU/L). Overall 92.46% infants showed a positive response to the vaccine. The females showed higher titers of antiHBs against vaccination as compared to that of males. Infants of urban areas showed higher titers as compared to that of rural areas. Conclusion: Our results reinforces that the Hepatitis B vaccine has a good tolerability and is highly immunogenic among infants. It is recommended that serosurvey of HBsAg and vaccine coverage at country level should be done.
ABSTRACT
Methicillin resistant Staphylococcus aureus (MRSA) and methicillin resistant coagulase negative staphylococci (MRCoNS) are the important nosocomial infectious agents. There is a growing concern about the rapid rise in the resistance of Staphylococcus aureus to presently available antimicrobial agents. The aim of this study was to evaluate the prevalence rate of MRSA and MRCoNS and their rate of resistance to different antistaphylococcal antibiotics used broadly for treatment. Out of the total 350 staphylococcal isolates from different clinical specimens 148 isolates (60.40%) were identified as MRSA by oxacillin screen agar method, and 46 isolates (43.80%) were screened as MRCoNS. All the MRSA and MRCoNS isolates were tested for antibiotic resistance pattern by disc diffusion method for 16 different antibiotics. All the isolates of MRSA and MRCoNS were multi-drug resistant. Antibiotic resistance pattern of these isolates was high against penicillin. All the MRSA strains were resistant to penicillin and oxacillin (100%), followed by cephalothin and nalidixic acid (89.18%), cotrimoxazole (86.48%), erythromycin (85.81%), cephalaxin and cephradine (83.10%), levofloxacin (80.40%), imipenem (77.70%), gentamicin (76.35%), tetracycline (59.45%), ciprofloxacin (44.59%), chloramphenicol (18.24%) and rifampicin (10.13%). The MRCoNS strains also showed closely similar drug resistance pattern with 97.82% isolates being resistant to penicillin, followed by oxacillin (95.65%), cephalothin (86.95%), cephradine (82.60%), levofloxacin and nalidixic acid (80.43%), erythromycin, cephalaxin and imipenem (78.26%), cotrimoxazole (73.91%), gentamicin (69.56%), ciprofloxacin and tetracycline (63.04%), chloramphenicol (13.04%) and rifampicin (6.52%). However, all the MRSA and MRCoNS isolates, even those with very high oxacillin MIC (>130 μg/ml) were uniformly susceptible to vancomycin. Chloramphenicol and rifampicin also showed excellent activity against methicillin-resistant isolates. Overall, data presented in this study indicated a slightly higher methicillin resistant rate in MRSA compared to MRCoNS strains. Multi-drug resistance rates in our MRSA and MRCoNS isolates were, 58.10 and 32.60%, respectively. Application of ß-lactamase production method revealed that 84% of MRSA and 87% of MRCoNS strains tested positive for the ß-lactamase production. This study indicated a high level prevalence of MRSA and MRCoNS strains resistance against widely used antimicrobial agents. An appropriate knowledge on the current antibiotic susceptibility pattern of MRSA and MRCoNS is essential for appropriate therapeutic regime determination.
ABSTRACT
Southern corn leaf blight caused by Cochliobolus heterostrophus is a major foliar disease of maize crop in Pakistan. The disease affects leaves, leaf sheaths, ears and maize grains. Suitable physiological conditions which include different nutrient media, temperature, pH, carbon and nitrogen sources were determined for growth and reproduction of the pathogen. Among all media used viz, the best supporting medium was found to be Richard’s agar for the growth of pathogen after 7 days of incubation. Different temperatures (20, 25, 30 and 35ºC) were selected for mycelia growth of the pathogen, among which maximum growth was found to be at 30ºC (80 mm colony size) and minimum at 35ºC (35 mm). Maximum radial colony growth of the pathogen was observed at neutral pH (80 mm). Sucrose and potassium nitrate (KNO3) were found to be the most appropriate sources of carbon and nitrogen respectively.