Clinical and epidemiological characteristic of enterovirus infection from 1993 until 2007 in Novosibirsk, Russia
Session I or V: Demina, A.: YI submission
Title of Contribution: Clinical and epidemiological characteristic of enterovirus
infection from 1993 until 2007 in Novosibirsk, Russia
Author(s): A.V. Demina1,2, S.V. Netesov2
1Municipal Isolation Clinical Hospital №1, Novosibirsk; 2FSRI State Research Center of Virology and Biotechnology «Vector», Koltsovo, Russia, 630559
Abstract:
The main purpose during last years in the world was poliovirus eradication. However, poliovirus elimination became the beginning of non-polioviruses evolution. The most of them spread by airborne way and fecal-oral route. Non-polio enteroviruses cause a wide variety of clinical diseases, frequently associated with the defeat of central nervous system. They are recognized now as the most common cause of viral meningitis (Lippincott W. & W., 2002).
Purpose: the study of the clinical and epidemiological peculiarities of enteroviral infection (in particular, one of its wide-spread forms – aseptic meningitis) in Novosibirsk, Russia.
Materials and methods: we have analyzed 883 histories of the disease of adult patients, which were being observed in Novosibirsk Municipal Isolation Clinical Hospital №1, with the diagnosis aseptic meningitis during the period from 1993 until 2007.
Results: this analysis revealed that during fifteen years the morbidity by enteroviral aseptic meningitis was considerably increased in Novosibirsk. There also were 3 significant outbreaks: in 1993 – 74 pat., 1998 – 97 pat., 2004 – 194 patients. Among the patients high portion comprised the persons younger 30 years (from 54% to 87,6%). The morbidity among the men was higher than among the women to 5-10%. The greatest number of diseases was in July - October. Although the sporadic morbidity is encountered all year around.
The main factors of infection were: swimming in reservoir (rivers, lakes) (30%); contact with the patients with aseptic meningitis or acute respiratory viral infection (12%); visiting of pioneer camps (6%); using of raw water (6%) and raw milk (2%). However, the large numbers of aseptic meningitis remain with unknown epidemiological anamnesis (44%).
The average degree of gravity of disease predominated in all years (from 64,5% - 1996 till 93,3% - 2004). Aseptic meningitis proceeded as acute, but rapidly cut short infection. However, it is not following its usual pattern from 2004 y. We observed the great number of additional symptoms, which are typical for the enteroviral infection: catarrhal inflammation (hyperemia of oral pharynx, herpangina) – 40%, rhinitis – 13 %, exanthema – 9%, scleritis – 5%, diarrhea – 5%.
The analysis of cerebro-spinal fluid showed that three-digit cytosis predominated in all years (55%-75% from 100 till 500 cells in 1 mm3); however there was bidigitate cytosis from 10 till 99 cells in 1 mm3 in 1999 – 67% and in 2003 – 60%. The nature of pleocytosis was neutrophilic, mixed or lymphocytic in the different years. It depended on the date of hospitalization from the beginning of clinical manifestation.
Diagnosis «enteroviral aseptic meningitis» was established on the basis of clinico-epidemiological work-up and it was confirmed by detection the RNA of enteroviruses by the method PCR: in 69,6% of patients - in the liquor, in 9% - in the blood and in 21,4% - in both cerebro-spinal fluid and blood.
Conclusion: Thus, based on particular example, we observe increase morbidity by non-polio enteroviral infections. This proves the evolution of non-polio enteroviruses whereas take place the elimination of poliovirus.
