ABSTRACT
From 2013 to 2015, the National Institute of Health, Pakistan, received 1,270 blood samples of suspected dengue cases reported from inpatient and outpatient departments of various hospitals in Khyber Pakhtunkhwa (KPK) province. In this study, we determined the circulating dengue virus (DENV) serotypes using real-time reverse transcriptase (RT)-PCR to understand the serotype-based epidemiology of DENV. All four serotypes (DENV-1 [6%], DENV-2 [33%], DENV-3 [47%], and DENV-4 [0.1%]) were found circulating during the study period. Our findings suggest the need for an active surveillance system coupled with the laboratory diagnosis, especially in the chronic endemic areas of the country. Public awareness programs are needed for effective control and prevention of outbreaks in the future.
Subject(s)
Adolescent , Adult , Female , Humans , Male , Middle Aged , Young Adult , Dengue/diagnosis , Dengue Virus/genetics , Disease Outbreaks , Pakistan/epidemiology , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction , SerogroupABSTRACT
Objective: To high light some epidemiological, clinical and diagnostic features of dengue fever during an outbreak and the role of different diagnostic techniques to achieve the highest level of accuracy in results. Methods: Blood samples (n = 323) were collected along with epidemiological and clinical data from suspected dengue patients who visited different hospitals in Swat and Mansehra district of Pakistan between May-November 2013 during a dengue outbreak. Samples were tested for the detection of viral nucleic acid by real-time PCR, non structural protein-1 (NS1) antigen and IgM antibodies by ELISA. Results: Out of 323 cases with clinical dengue infection, 304 were positive by one or more diagnostic parameter; 201 samples were positive by real-time PCR, 209 were positive by NS1 ELISA and 190 were positive by IgM antibodies. Sensitivities of real-time PCR and NS1 ELISA were comparable for early diagnosis of dengue virus infection, IgM antibody detection assay was found useful for the diagnosis in the samples collected later than day 5 of onset. Conclusions: The use of real-time PCR or detection of non structural protein NS1 by ELISA followed by IgM antibodies detection can be recommended for early diagnosis of dengue virus infection with a high level of accuracy.
ABSTRACT
Objective To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection. Methods The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELISA and its comparison with viral RNA detection via real time PCR and IgM antibodies detection by ELISA. Results A total of 1270 serum samples were tested 86% (1097/1270) were detected positive by one or more than one diagnostic test. Out of 1 270, 64% (807/1270) were positive by NS1 ELISA and 52% (662/1270), 51% (646/1270) were positive by real-time RT-PCR and IgM ELISA respectively. Conclusions NS1 antigen detection ELISA is highly suitable diagnostic tools and it also has great value for use in outbreak and epidemic situation.
ABSTRACT
OBJECTIVE@#To high light some epidemiological, clinical and diagnostic features of dengue fever during an outbreak and the role of different diagnostic techniques to achieve the highest level of accuracy in results.@*METHODS@#Blood samples (n = 323) were collected along with epidemiological and clinical data from suspected dengue patients who visited different hospitals in Swat and Mansehra district of Pakistan between May-November 2013 during a dengue outbreak. Samples were tested for the detection of viral nucleic acid by real-time PCR, non structural protein-1 (NS1) antigen and IgM antibodies by ELISA.@*RESULTS@#Out of 323 cases with clinical dengue infection, 304 were positive by one or more diagnostic parameter; 201 samples were positive by real-time PCR, 209 were positive by NS1 ELISA and 190 were positive by IgM antibodies. Sensitivities of real-time PCR and NS1 ELISA were comparable for early diagnosis of dengue virus infection, IgM antibody detection assay was found useful for the diagnosis in the samples collected later than day 5 of onset.@*CONCLUSIONS@#The use of real-time PCR or detection of non structural protein NS1 by ELISA followed by IgM antibodies detection can be recommended for early diagnosis of dengue virus infection with a high level of accuracy.
ABSTRACT
OBJECTIVE@#To evaluate NS1 antigen detection ELISA for the early laboratory diagnosis of dengue virus infection.@*METHODS@#The present study was conducted to evaluate the overall positivity of NS1 antigen detection ELISA and its comparison with viral RNA detection via real time PCR and IgM antibodies detection by ELISA.@*RESULTS@#A total of 1270 serum samples were tested 86% (1097/1270) were detected positive by one or more than one diagnostic test. Out of 1 270, 64% (807/1270) were positive by NS1 ELISA and 52% (662/1270), 51% (646/1270) were positive by real-time RT-PCR and IgM ELISA respectively.@*CONCLUSIONS@#NS1 antigen detection ELISA is highly suitable diagnostic tools and it also has great value for use in outbreak and epidemic situation.
ABSTRACT
Diphtheria is a communicable disease of global significance, and its outbreaks have to be reported to the world community under the International Health Regulations [IHR]. A pilot seroepidemiological survey was conducted to assess immunity status of diphtheria among healthy individuals of Rawalpindi/Islamabad [Pakistan], who had been administered at least one dose of the vaccine against the disease, as part of childhood vaccination. The study group comprised of 128 healthy subjects, grouped according to the decade representing their age. Antidiphtheria IgG levels were measured by Enzyme Linked Immunosorbent Assay [ELISA] method. The studied sample showed 100% prevalence of diphtheria antitoxin, confirming prior vaccination; however 49.2% exhibited only minimal protection against diphtheria. Full protection was observed in a significantly higher [p=0.013] percentage of males [54.45%] as compared to female subjects [33.33%]. Maximum level of serum antibodies were seen in 1-10 year age group [0.195+0.031 IU/mL], which was significantly higher than that recorded in the age group of 11-20 [p=0.024] and above 30 years [p=0.0064]. The present results emphasize the need for periodical booster immunization in adolescents and adults, after primary childhood immunization