Frequency of lymphocytic meningitis associated with mumps before and after a mass campaign for mumps vaccination in children from Salvador, Northeast Brazil.

OBJECTIVE: To describe the frequency of lymphocytic meningitis(LM) concomitant with mumps, before and after the mumps mass immunization campaign in 1997. METHOD: Demographic, clinical and cerebrospinal fluid(CSF) information was collected from the chart of all patients aged from 2 to 59 months, whose CSF exam was performed at the CSF Lab/FJS, between 1989 and 2001. LM was defined as pleocytosis composed by lymphomononuclear cells and negative exams for bacterial or mycologic infection. RESULTS: Of 1,519 patients, 894(58.9%) had normal exams. LM was present in 301(19.8%) patients, out of which 22(7.3%) had concomitant mumps. The frequency of LM ranged from 15.8% in 1989 to 19.7% in 2001 and of LM with concomitant Mumps ranged from 10.5% in 1989 to 4.7% in 1995, when the last cases were registered. CONCLUSION: It is probable that the mumps vaccine campaign has influenced the absence of LM with concomitant Mumps, from 1996 to 2001.

Nested PCR for rapid detection of mumps virus in cerebrospinal fluid from patients with neurological diseases.

In this study, we have developed a reverse transcription (RT)-nested polymerase chain reaction (n-PCR) for the detection of mumps virus RNA in cerebrospinal fluid (CSF) from patients with neurological infections. A specific 112-bp fragment was amplified by this method with primers from the nucleoprotein of the mumps virus genome. The mumps virus RT-n-PCR was capable of detecting 0.001 PFU/ml and 0.005 50% tissue culture infective dose/ml. This method was found to be specific, since no PCR product was detected in each of the CSF samples from patients with proven non-mumps virus-related meningitis or encephalitis. Mumps virus RNA was detected in all 18 CSF samples confirmed by culture to be infected with mumps virus. Positive PCR results were obtained for the CSF of 26 of 28 patients that were positive for signs of mumps virus infection (i.e., cultivable virus from urine or oropharyngeal samples or positivity for anti-mumps virus immunoglobulin M) but without cultivable virus in their CSF. Overall, mumps virus RNA was detected in CSF of 96% of the patients with a clinical diagnosis of viral central nervous system (CNS) disease and confirmed mumps virus infection, while mumps virus was isolated in CSF of only 39% of the patients. Furthermore, in a retrospective study, we were able to detect mumps virus RNA in 25 of 55 (46%) CSF samples from patients with a clinical diagnosis of viral CNS disease and negative laboratory evidence of viral infection including mumps virus infection. The 25 patients represent 12% of the 236 patients who had a clinical diagnosis of viral CNS infections and whose CSF was examined at our laboratory for a 2-year period. The findings confirm the importance of mumps virus as a causative agent of CNS infections in countries with low vaccine coverage rates. In summary, our study demonstrates the usefulness of the mumps virus RT-n-PCR for the diagnosis of mumps virus CNS disease and suggests that this assay may soon become the "gold standard" test for the diagnosis of mumps virus CNS infection.