Diagnosis, treatment of TB: state lab is partner.

Between 1992 and 1995, there was a 14.5 percent decline in the number of TB cases reported annually in the United States and a 10.3 percent decline in Pennsylvania. The CDC credits improved laboratory methods to allow prompt identification of M. tuberculosis and the broader use of drug-susceptibility testing among the factors responsible for the decline.

High incidence of congenital rubella syndrome after a rubella outbreak.

Previous studies of the incidence of congenital rubella syndrome (CRS) after rubella outbreaks have been limited because most women with infection during the first trimester elected to have their pregnancies terminated. After a rubella outbreak in 1991 we measured prospectively the impact of maternal infection on CRS among the Amish in one county in Pennsylvania. We compared rubella serology of Amish women delivering before and after the outbreak and cord blood rubella IgM from Amish and non-Amish infants. Before the outbreak 20% of Amish women were susceptible to rubella; after the outbreak 4% were (P = 0.001). Of Amish infants 15% tested positive for rubella IgM; no non-Amish infants did (P < 0.001). This rubella outbreak in a largely unimmunized community led to a high rate of CRS. The annual CRS rate among the Amish was 2130/100,000 live births. Health care providers should promote immunization in all clients and intensify efforts among the Amish.

Comparison of the MEASLESTAT M test kit with the sucrose density gradient centrifugation-hemagglutination inhibition method for detection of measles virus-specific immunoglobulin M.

A new commercial kit, MEASLESTAT M (Whittaker Bioproducts, Inc.), was compared with the sucrose density gradient centrifugation-hemagglutination inhibition method for the detection of measles virus-specific immunoglobulin M. Overall agreement between the two procedures was 97.1% for 104 single and paired serum samples tested. The sensitivity and specificity of MEASLESTAT M were 98.4 and 95.2%, respectively.

Evaluation of direct wet mount parasitological examination of preserved fecal specimens.

A retrospective study covering a 12-year period was performed to determine the contribution of the direct wet mount microscopic examination to the identification of intestinal parasites in preserved fecal material. It was determined that each of 898 specimens contained at least one parasite when processed by the direct wet mount, concentration, and trichrome staining procedures. Of these procedures, the direct wet mount examination was solely responsible for the identification of 45 (2.9%) of 1,581 parasites identified. This is in contrast to the 15.1 and 12.5% which were found exclusively by the concentration and trichrome methods, respectively. These percentages may vary, depending on the prevalence of parasites and the stages present in the stool specimen.

Evaluation of NCS rapid plasma reagin card test, a new screening kit for syphilis.

Agreements in qualitative and quantitative test results between the recently marketed NCS rapid plasma reagin card test (NCS Diagnostics Corp.) and the Macro-Vue rapid plasma reagin 18-mm circle card test (Hynson, Westcott and Dunning) were 99.2 and 99.1%, respectively, indicating the NCS RPR card test to be an acceptable alternative procedure for the serodiagnosis of syphilis.

Hemo-De as substitute for ethyl acetate in formalin-ethyl acetate concentration technique.

In comparative studies, Hemo-De (PMP Medical Industries, Inc., Irving, Tex.) was found to be a suitable replacement for ethyl acetate in the Formalin-ethyl acetate concentration technique. With essentially equivalent recovery rates for both procedures, the Formalin-Hemo-De concentration technique is considered to be the preferred technique because Hemo-De is less toxic and less flammable and does not present disposal problems, and its cost is approximately one-fourth that of ethyl acetate.

Comparison of MYCOPLASMELISA with complement fixation test for measurement of antibodies to Mycoplasma pneumoniae.

The MYCOPLASMELISA test kit was compared with the complement fixation test for detection of Mycoplasma pneumoniae antibody in single sera and evaluation of acute- and convalescent-phase serum pairs for significant rises in antibody titers. Agreement between the two assays was 96.6% (85 of 88) for antibody detection and 93.9% (92 of 98) for evaluation of paired sera. Sensitivity and specificity of MYCOPLASMELISA, relative to complement fixation, for the serodiagnosis of recent M. pneumoniae infection was 92.2% (59 of 64) and 95% (19 of 20), respectively.

Reactivity of Dade rapid plasma reagin card test with low-titer sera.

Of 105 sera having reagin titers of 1 dilution as determined by the rapid plasma reagin 18-mm circle card test (Hynson, Westcott and Dunning, Baltimore, Md.), 103 (98.1%) were reactive with the Dade rapid plasma reagin card test (Biokit Laboratories, Barcelona, Spain), indicating that the two procedures are comparable in their ability to detect low levels of nontreponemal syphilitic antibody, or reagin.

Epidemic of meningitis and febrile illness in neonates caused by ECHO type 11 virus in Philadelphia.

Between April and November, 1980, an outbreak of meningitis and of febrile illness of neonates caused by ECHO 11 virus occurred in Philadelphia and surrounding communities. Thirty-eight virologically confirmed and ten virologically presumptive cases of meningitis were hospitalized in two Philadelphia hospitals for children. Most patients had fever and irritability. Vomiting, upper respiratory symptoms and poor feeding were present in one-third to one-half of the cases. Seventy-five percent of cases occurred between June 10 and August 18. The number of males and females was similar; 71% of children were 4 months of age or younger. This out break differed from those previously reported on enteroviruses in general, and on ECHO 11 virus in particular, in that no strong male predominance occurred and the patients were younger. A minimum attack rate of 4.1 per 1000 Philadelphia resident children ages 1 day to 4 months was estimated.

Comparison of injected and oral polio vaccine for booster immunization during the 1979 polio outbreak in Lancaster County, Pennsylvania.

During a 1979 outbreak of poliomyelitis in Lancaster County, Pennsylvania, we investigated the necessity for and the response to booster vaccination of hospital personnel. The immune response of hospital employees who received booster injections of Salk vaccine (n = 38) was compared with that of residents in the surrounding community who received Sabin trivalent OPV boosters (n = 43). Serum neutralizing antibody titers to the three polio serotypes were measured before and after booster immunization. Results indicated that 38% of the subjects in both groups had low initial antibody titers. Salk vaccine was in all circumstances as effective or better than Sabin vaccine in increasing neutralizing IgG antibody titers.

Detection and identification of diagnostic Histoplasma capsulatum precipitates by counterelectrophoresis.

Studies were carried out to develop and evaluate a counterelectrophoresis (CEP) technique for the rapid and specific identification of the diagnostically important histoplasmosis H and M precipitin bands. Well-defined and centrally located precipitin bands were produced by using a discontinuous buffer system and a gel matrix composed of agarose and ionagar no. 2. A template was devised which allowed the selective identification of the H and M precipitins. Comparative evaluations were performed with the microimmunodiffusion (ID) and complement fixation tests. In 52 sera from persons with histoplasmosis, either the H or M precipitin, or both, were identified in 42 (81%) of the cases with the CEP technique and in 43 (83%) with the ID test. With sera from 28 persons with heterologous diseases, the CEP technique, like the ID test, failed to react. The specificity of the CEP technique was dependent upon the use of the identity template. The CEP technique is recommended for routine use in laboratories testing moderate numbers of sera. It provides accurate and reproducible results within 90 min, in contrast to the ID test, which requires 18 to 24 h.