Evaluation of Rapid Neutralizing Antibody Detection Test against Rabies Virus in Human Sera

Rapid and easy determination of protective neutralization antibody (NAb) against rabies in the field is very important for an early and effective response to rabies in both animal and human health sectors. The rapid neutralizing antibody detection test (RAPINA), first developed in 2009 and then improved in 2012, is a quick test allowing detection of 0.5 IU/ml antibodies in human and animal sera or plasma. This study aimed to assess the RAPINA test by comparison with rapid focus fluorescence inhibition test (RFFIT), using 214 sera of vaccinated and unvaccinated professional dog butchers, laboratory workers and rabies patients in Vietnam. The sensitivity, specificity, false negative rate, false positive rate and concordance of the RAPINA test as compared to RFFIT were 100%, 98.34%, 0%, 1.66% and 98.6%, respectively. The positive predictive value and negative predictive value were 91.7% and 100%, respectively when RAPINA test was used. With its remarkable sensitivity, specificity and easy implementation, RAPINA test can be used for rapid determination of NAb in the field.