First epidemic of echovirus 16 meningitis in Cuba.

From April to September 2000, an epidemic of aseptic meningitis spread throughout Cuba, with 16,943 reported cases. Virologic studies identified echovirus 16 as the cause of this epidemic. This is the first reported isolate of echovirus 16 from patients with viral meningitis in Cuba.

Persistence of vaccine-derived poliovirus following a mass vaccination campaign in Cuba: implications for stopping polio vaccination after global eradication.

BACKGROUND: With substantial progress made toward polio eradication, developing the appropriate strategy for discontinuing global oral poliovirus vaccine (OPV) after global eradication becomes increasingly important. At issue is the theoretical risk of independent circulation of potentially virulent OPV-derived strains. Because Cuba uses OPV only in mass campaigns, it represents an ideal site to assess vaccine-derived poliovirus persistence. METHODS: Infants born after the 1997 biannual mass campaigns were evaluated for past (neutralizing antibody) or current (virus excretion) evidence of vaccine-derived poliovirus exposure. We obtained sera and/or stool specimens from 861 infants; a second serum from 218 infants. RESULTS: All stool specimens were poliovirus negative. Of 762 infants, 113 (14.8%) had initially detectable poliovirus type 1 antibody, 193 (25.3%) type 2, and 94 (12.3%) type 3. A precipitous antibody decline occurred in initially positive sera. CONCLUSIONS: Our results suggest that in a country with high population immunity, vaccine-derived virus is unlikely to establish ongoing circulation.

[Contribution to knowledge about the permanence and circulation of poliovirus vaccine in the environment]. / Aportes al conocimiento acerca de la permanencia y circulación del poliovirus vacunal en el ambiente.

The erradication of poliomyelitis in the world is a goal that requires the adoption of effective and safe strategies for its attainment. Knowing how long the strains of poliovirus derived from the oral attenuated virus vaccine may circulate and remain in the environment was essential to define the measures to be taken and was also the objective of our paper. Specimens of stools and sewage water, which were weekly obtained at the end of the National Polio Vaccination Campaign, in 1998, were analyzed. Viruses were isolated and identified by culture and neutralization tests for the identification of poliovirus. In the particular case of the sewage water, it was also used the polymerase chain reaction. The curves of elimination in both media were drawn and it was concluded that the permanence of viruses in the environment did not exceed the 12 weeks after the immunization with the oral attenuated virus vaccine.

Meningoencefalitis virales por Enterovirus en Cuba en el período 1990-1995 / Viral meningoencephalities due to enteroviruses in Cuba during 1990-1995

Se describen los resultados del estudio de enterovirus como agentes causanes de meningoencefalitis viral (MEV) en Cuba, desde 1990 hasta 1995. En este período fueron estudiados 586 muestras de heces, 108 líquidos cefalorraquídeos y 1095 sueros pareados para un total de 1789 muestras, procedentes de 1458 pacientes diagnosticados clínicamente con esta patología. Las muestras para el aislamiento viral se inocularon en dos sistemas celulares diferentes, encontrándose 225 muestras positivas a enterovirus que representan el 32,42 o/o del total; el mayor número de aislamientos (217) fue a partir de heces, en células diploides de fibroblastos de pulmón humano (PHuE-1). Las determinaciones de anticuerpos se realizaron por prueba de neutralizacion en micrométodo, enfrentándolos con 10 antígenos de enterovirus (Echovirus 4, 6, 9, 11 y Coxsackievirus B1-6) y, en períodos epidémicos, además con el virus aislado. En los años estudiados se produjeron tres brotes epidémicos por Coxsackievirus A9 (1990-91), Echovirus 30 (1994) y Coxsackievirus B5 (1995). Es de señalar que desde 1970 los Coxsackievirus A9 y Echovirus 30 se vincularon en nuestro país, por primera vez, con epidemias de MEV. En los sueros pareados se obtuvo 66,84 o/o de positivos, siendo la mayor positividad a los Echovirus 6 y 11. Al considerar en conjunto la positividad por aislamiento y serología, más del 80 o/o de los casos estudiados pudieran tener ua explicación por algún enterovirus, lo uqe demuestra la importancia de estos agentes como causantes de MEV en Cuba

[Outbreak of Coxsackievirus B5 meningoencephalitis in Cuba, 1995]. / Brote de meningoencefalitis por coxsackievirus B5 en Cuba, 1995.

An increase in the reported cases of viral meningoencephalitis (VME) was detected in October and November, 1995, compared with the same period of 1994. 43 stock specimens from children with this diagnosis were received at the Laboratory of Enterovirus from the "Pedro Kourí" Institute of Tropical Medicine. 23 isolations (53.4%) were obtained and identified as Coxsackievirus B5. Besides, in 43 matched sera investigated by the neutralization test against some Enteroviruses, 21 proved to be positive (48.8%) to the isolated agent. This allowed us to affirm, supported by the clinical picture and by epidemiology, that we are in the presence of an VME outbreak produced by Coxsackievirus B5.

[Enterovirus meningoencephalitis in the last 5 years]. / Meningoencefalitis por Enterovirus en los últimos 5 años.

The results of the study of Enterovirus as viral meningoencephalitis producing agents, carried out from 1990 to 1994, are described, 546 feces samples, 95 cerebrospinal fluids and 1,058 matched sera were studied and obtained from 1,388 patients clinically diagnosed with this disease. Samples for viral isolation were inoculated into two different cellular systems. The highest number of isolation was found in diploid cells from human fibroblast. Antibody determinations were carried out by a neutralization test (micromethod) with 11 Enterovirus antigens (Echo 4, 6, 9, 11 and 30; and Coxsackie B1, 2, 3, 4, 5 and 6) and in epidemic periods with the isolated virus. During the years under study, 2 epidemic outbreaks took place: on caused by Coxsackie A9 (1990-1991) and the other one by Echo 30 (1994). A greater positivity to Echo 6 and 11 was found among the matched sera.

[Cuban epidemic neuropathy. III. Neutralizing antibodies to the strains isolated and to other enteroviruses in patients and healthy subjects]. / Neuropatía epidémica cubana. Parte III. Anticuerpos neutralizantes a cepas aisladas y otros Enterovirus en pacientes y personas sanas.

Determinations of neutralizing antibodies to the strain 47/93 IPK (CA9) and to the strain 590 were performed in serum samples from patients presenting with epidemic neuropathy and from a group of seemingly healthy subjects. Determinations were also done in the reference strains CA9 and CB1-6 by the microneutralization technique. Patients and their contacts showed significantly higher percentages of neutralizing antibodies to the strain 47/93 than the control group and residents of municipalities with a low rate of the disease. This difference was also confirmed regarding the geometric mean titres with the use of the reference strains CA9 and CB2-4. An increased circulation of the strain 47/93 within the infantile population from 1981 to 1993 was evidenced. Patients exhibited significantly lower percentages and geometric mean titres of neutralizing antibodies to the strain 590 than the control group, despite the fact that in 25/28 certain agents having a mild cytopathogenic effect had been isolated. The possibility of two mechanism of neutralization is stated and an hypothesis on the mechanism by which these viruses may be involved in the pathophysiology of the disease is formulated.

[Development and evaluation of an ELISA for the detection of IgM antibodies against the hepatitis A virus]. / Desarrollo y evaluación de un ELISA para la detección de anticuerpos IgM contra el virus de la hepatitis A.

We present the results of the normalization of an IgM capture ELISA method for the diagnosis of type A viral hepatitis with reagents produced in the laboratory and its comparison with the "Diag-A-Hep" commercial ELISA. The results attained were: sensibility by 91%; specificity by 100%; and coincidence of the two systems by 97%. Results are discussed and their relationship with clinical symptoms and epidemiological characteristics is established. The results attained in 13 serum samples taken from patients seen during 2 acute viral hepatitis outbreaks agreed with clinical findings.