Retrospective epidemiologic diagnosis of viral non-A, non-B hepatitis with a fecal-oral mechanism of transmission of the causative agent

The possibility of the retrospective epidemiological diagnosis of viral hepatitis non A, non B with the fecal-oral mechanism of the transfer of infection in three cities of Central Asia on the basis of the analysis of the dynamics of registered hepatitis A morbidity is shown. With the irregularity of morbidity levels among the total population being characteristic of all three cities, in Andizhan one rise in morbidity within a period of 3 years (1975-1978) and in Tashauz one rise within a period of 5 years (1975-1980) were registered. The analysis of the dynamics of morbidity observed in individual age and social groups showed that these rises, especially those registered in 1976 in Andizhan and in 1977 in Tashauz, were determined by morbidity levels among school children and adults. This is also true for a rise in morbidity rate registered in Tashauz in 1985. In Andizhan the highest morbidity rates among adults were registered in districts insufficiently equipped with modern amenities. Cases of infection registered as hepatitis A (HA) among persons immune to HA at territories with high intensity of the epidemic process of HA at the above-mentioned periods seem to be due to viral hepatitis non A, non B with the fecal-oral mechanism of the transmission of the infective agent.     

Zonal characteristics of the dynamics of viral hepatitis A morbidity over a period of many years (based on data from the Ukrainian SSR)

The previously established zonal character of the prevalence of viral hepatitis A in the Ukraine is a stable epidemiological regularity observed for more than 30 years (1952-1985). Zonal differences in the dynamics of the epidemic process of viral hepatitis A were established. These differences became particularly hepatitis manifest in the years of periodic rises in the morbidity rate which is also irregular within zonal and regional boundaries. The main typological variants of the dynamics of the epidemic process ("urban" and "rural") were defined. Typological approach appears to be useful in the provision of information necessary for the proper functioning of epidemiological surveillance and for taking measures aimed at epidemics control.     

Prognosis of the dynamics and intensity of the epidemic process in viral hepatitis A

The article deals with approaches to the calculation of the annual morbidity rate in virus hepatitis A at the period preceding the season of maximum morbidity, necessary for planning the relevant prophylactic and antiepidemic measures in due time. The method for calculating the monthly levels of sporadic morbidity in virus hepatitis A is proposed. This method permits the detection of complications on the epidemic situation, which is necessary for the timely organization of antiepidemic measures. The proposed method for predicting annual and monthly morbidity levels can be used in the practical work of specialists at sanitary and epidemic stations.     

Epidemiological analysis of hepatitis A morbidity

A retrospective epidemiological analysis of hepatitis A morbidity for many years among the population of two neighboring towns in the temperate climatic zone of the USSR has revealed the cyclic character of the epidemic process without a perceptible decrease in its extensiveness and has determined the high-risk groups, as well as the beginning of the seasonal rise of morbidity in these groups. The results of the study indicate that different levels of hepatitis A morbidity and risk groups can be observed in these two neighboring towns. At periods of a lower morbidity level the high-risk group embraces schoolchildren, and when morbidity is at a higher level the risk group includes schoolchildren and preschool children in organized groups. Among the latter the morbidity level is influenced by factors acting all the year round and among school children, by seasonal factors. The beginning of the seasonal rise of morbidity falls on August, while in organized groups of children of preschool age the seasonal rise of hepatitis A morbidity begins 1-1.5 months later. All prophylactic measures for controlling hepatitis A should be carried out with due regard to these features of the epidemic process.     

Characteristics of the epidemic process manifested as chronic viral hepatitis

The incidence rates of chronic viral hepatitis in Leningrad over the period of 1962-1984 were studied. The tendency towards a rise in total morbidity because of increased incidence of chronic hepatitis B was shown to appear in recent years. This increase in morbidity was mainly due to its rise among adult males and children, which led to the shift of morbidity to younger age groups. The seasonal rises of morbidity in winter and spring were found to be characteristic of viral hepatitis.     

Spread of hepatitis virus as a threat to national security

Information on viral hepatitis A, B and C morbidity in Russia is presented. A distinct trend to decreased viral hepatitis B and C morbidity in 2001-2002 in comparison with the 1990-ies is noted. Nevertheless, there is still unfavorable prognosis regarding high hepatitis B morbidity among the population of reproductive age, as well as among adolescents, which increases the risk for children at an early age. In addition, a new specific feature of hepatitis A spread is observed: morbidity in this infection is shifted to older age groups. The role of vaccinal prophylaxis in the decrease of hepatitis A and B morbidity, virus safety of blood and its components, the quality of the diagnostics of chronic hepatitis, especially hepatitis C, are discussed. The complex of measures for the prophylaxis of viral hepatitis is proposed.     

Various epidemiological principles of the spread of viral hepatitis in the Astrakhan district]

Analysis of many-year changes in the vitral hepatitis incidence in the Astrakhan region showed a significant cyclicity of the epidemic process: its incidence rose 4 times during the period of from 1957 to 1976; four of these elevations were comparatively high (in 1960, 1964, and 1974). Lately the group of children aged from 3 to 7 years has been of the greatest epidemiological significance, but at present greatest incidence of the disease fell on the group of persons aged from 8 to 14 years. This can be connected with gamma-globulin vaccinations given to children aged under 10 years. Seasonal distribution of morbidity in different are groups was about the same and reflected the general automn-winter seasonal prevalence.     

The cause of the activation of an epidemic process of intestinal infections in the 70s]

In the seventies a considerable rise in dysentery morbidity was observed in all republics of the USSR, in the whole of the USSR, in Bulgaria and in the German Democratic Republic. An increase in cholera morbidity in the world, as well as in the number of countries affected by this infection, was registered. A tendency towards a rise in virus hepatitis incidence was observed in the USSR. The dynamic study of the ozone content in the stratosphere, solar activity, disturbances in the magnetic field of the Earth, air temperature for the period of 1967-1980 was carried out. Strong and moderate correlation between dysentery and air temperature in summer was established. The maximum morbidity level in the USSR in 1972 was probably the consequence of unusually high air temperature in summer.     

Characteristics of the manifest and latent components of the hepatitis A epidemic process in cities of Russia

Seroepidemiological study of hepatitis A (HA) morbidity was carried out in three Russian cities, with different levels of HA morbidity. The study included the analysis of HA morbidity for 22 years, the determination of antibodies to HA virus (anti-HAV) in 2,958 healthy persons aged 0-12 months to 40 years and older. In one of the cities 7 isolates of HA virus were obtained from unrelated sources and the genotypes of the virus were determined. The study revealed that the frequency of seropositive cases among persons of different ages correlated with the level and prolonged dynamics of HA morbidity. According to the occurrence of anti-HAV, such cities as St. Petersburg, Rostov-on-Don and Yakutsk may be at present classified as territories, moderately endemic in HA. At the same time in the 90 s the epidemic situation in HA was more favorable in Rostov-on-Don than in two other cities. The suggestion was made that a high proportion of seropositive persons among the population of St. Perersburg was linked with an almost twofold rise in HA morbidity in 1993-1995 caused by genotype 1 of the virus. Seroepidemiological studies in HA during the period of a drop in morbidity acquire special importance in the surveillance and control system of this infection.     

Prevalence of viral hepatitis among the hospital staff in CSR between 1980 and 1982

The hepatitis morbidity data were used to study prevalence rate of manifest viral hepatitis among the hospital staff members in CSR over a 3-year period between 1980 and 1982. This study showed that the overall hepatitis morbidity rate was 2.68 per 1,000 health personnel and was 3.6 times as high as that recorded in a normal population matched by age. The mean HBsAg positivity rate was 1.67 per 1,000 and was 5.8 times the rate in the control population group. The rate of HBsAg-negative cases of hepatitis was 1.01 per 1,000 health personnel and was higher than double the rate of morbidity encountered in an age-matched normal population. The highest morbidity rates were recorded in the lower-grade and auxiliary health personnel. When compared with an age-matched normal population the hospital staff members at all departments had distinctly higher morbidity rates than the general population, but the highest risk of acquiring viral hepatitis was evidently run by the personnel at departments of renal dialysis, biochemistry, hematology, infectious diseases, internal medicine, surgery, urology and TRD (tuberculosis and respiratory diseases). Of a total number of recorded cases of viral hepatitis those with HBsAg positivity predominated, especially at departments of urology, TRD, internal medicine, renal dialysis, psychiatry and hematology. Analyzed by specialty and professional status of personnel these viral hepatitis morbidity rates encountered among the hospital staff members seem to point to at least two conclusions: this infection in the health personnel is work-related and its transmission and spread is dependent on the frequency and intensity of contact with the blood and other secretions of infectious patients.     

HIV infection and parenteral virus hepatitis in the Krasnodar territory

The analysis of the morbidity dynamics of HIV infection, hepatitis B and C in the Krasnodar territory for 1996-2003 is presented. The tendency of strengthening direct correlation between age-dependent rates in these groups of diseases has been established. The correlation coefficient (rxy) is at present +0.851 (HIV infection-virus hepatitis B) and +0.892 (HIV infection-virus hepatitis C). The highest levels of primary morbidity are registered in persons aged 20-39 years. The established epidemiological parallels between HIV infection and parenteral hepatitis require the development of the unified strategy of the prophylaxis of these diseases on the federal and regional levels.     

Prophylactic efficacy of reaferon in viral hepatitis A and acute respiratory infections in children

Reaferon, the analog of human alpha 2-interferon obtained by gene engineering techniques, was studied with a view to its use for the prevention of hepatitis A. The study involved children of preschool age in Tashkent. In a strictly controlled trial children aged 2-6 years received the preparation orally in a dose of 1 X 10(6) I. U. or the diluent alone used as placebo. The preparation was administered to 1,100 children and the placebo to 1,078 children. The preparation and placebo were administered twice a week for two months. On the whole, during that period hepatitis A morbidity in both test and control groups of children was the same (5.1% and 4.9% respectively), but among children of nursery age receiving Reaferon the incidence of hepatitis A and acute respiratory viral infections was lower than among those receiving the placebo, though this difference was statistically significant only for cases of acute respiratory infections.     

Prevention of acute enteric infections and viral hepatitis A in the Krasnodar Territory appearing in connection with a natural disaster in 2002

Materials on the sanitary and epidemiological situation in the Krasnodar Territory in connection with emergency situations (intensive snowfalls, heavy showers, high floods) in 2002 are presented. The scope of the destruction of the systems ensuring the life provision of the population in the affected regions of the territory is shown. To carry out the epidemiological surveillance on acute enteric infections, to make corrections of the planned prophylactic measures, as well as the timely solutions of problems connected with controlling the epidemiological situation, the daily monitoring of the level and dynamics of infectious morbidity in individual settlements among different age and professional groups, as well as the foci of infections, was established. 65 cases of acute enteric infection and 4 cases of viral hepatitis A were registered in the affected areas, which did not exceed the average morbidity figures for many years. A complex of sanitary, hygienic and prophylactic measures was carried out by the sanitary and epidemiological service of the territory, which made it possible to maintain human morbidity in acute enteric infections and viral hepatitis A in the affected areas on the sporadic level.     

Analysis of the seasonality of acute intestinal diseases with regard to the detection of dysentery by antigen indication

Coincidence in the seasonal changes of the registered morbidity in dysentery and in other acute intestinal diseases is observed. The occurrence of Shigella antigens, detected with the use of erythrocyte diagnostic reagents, in the excreta of patients with the clinical diagnosis of dysentery and patients with other acute intestinal disease has a seasonal character, its peak coinciding with the period of increased morbidity in bacteriologically confirmed dysentery. The correction of monthly morbidity levels in dysentery and in other acute intestinal diseases with due regard for the proportion of Shigella antigens in the findings, made in the groups of patients with the clinical diagnosis of dysentery and with the diagnosis of other acute intestinal diseases for the corresponding month, has revealed that the actual morbidity in other acute intestinal diseases has a less pronounced seasonal character in comparison with the registered morbidity. This fact substantiates the statement that in the group of patients with other acute intestinal diseases a large proportion of such diseases is, actually, of a noninfectious nature.     

Morbidity in acute virus hepatitis B on the territory of Kabardin-Balkaria

Morbidity in acute virus hepatitis B (AVHB) in Kabardin-Balkaria during the period of 1992 to 2003 was analyzed. The dynamics of changes in the age groups of AVHB patients, as well as in the structure of the transmission routes of the disease, was analyzed. The level of AVHB morbidity in the Kabardin-Balkar Republic was lower in recent years than the average level of such morbidity in the whole of Russia. The sharply defined irregularity in the territorial distribution of AVHB cases was established. The highest morbidity rates in AVHB were registered in Nalchik, as well as in Chegem and Prokhladnensk regions. The leading role in the formation of the morbidity in acute virus hepatitis B on the territory of Kabardin-Balkaria belongs to Nalchik, where 56.8% of AVHB cases were registered. In the structure of the transmission routes of AVHB the prevalence of artificial paths was noted; among them, the highest proportion belonged to parenteral medical manipulations in outpatient clinics (32.9%). The proportion of AVHB cases associated with the intravenous use of drugs was 6.9%. In the age structure of AVHB patients adults prevailed, and among them the highest number of cases was registered in the age groups of 20 - 29 years and 30 - 39 years. In 2002 the total proportion of AVHB cases among the patients of these age groups reached 68.3%.     

Epidemiology of viral hepatitis in the Estonian SSR

The epidemiological peculiarities of viral hepatitis in the Estonial SSR as a whole, as well as in Tallinn and in the surrounding Harju region were studied. The study revealed that during the last 10 years the total decrease of morbidity in viral hepatitis was observed due to a decrease in infectious hepatitis, pronounced periodic and seasonal morbidity fluctuations being absent. A sharp decrease in infectious hepatitis morbidity had been achieved by carrying out planned gamma globulin prophylaxis among children. Viral hepatitis morbidity in the republic was determined by the adult population and manifested as sporadic cases of infectious and serum hepatitis. Infectious hepatitis was transmitted mainly through every day contacts, while the leading factor in the transmission of serum hepatitis consisted in various injections. The relatively high morbidity level of serum hepatitis was mainly determined by morbidity in large cities.     

Seasonal dynamic of the numbers of epiphytic yeasts

The numbers of epiphytic yeasts on the leaves and flowers of 25 plant species throughout their vegetation period was determined. The numbers of yeasts on the leaves were found to change regularly throughout the year. The average dynamics for all of the plant species investigated included an increase in yeast numbers during spring and summer with the maximum in late autumn and early winter. The character of the yeasts’ dynamics depends on the ecological characteristics of the plants and the duration of the ontogenesis of their leaves and flowers. Three types of dynamics of epiphytic yeasts were revealed: year-round with an increase in autumn-winter, year-round without visible changes, and seasonal with a terminal increase for annual plants.     

Seasonal dynamic of the numbers of epiphytic yeasts

The numbers of epiphytic yeasts on the leaves and flowers of 25 plant species throughout their vegetation period was determined. The numbers of yeasts on the leaves were found to change regularly throughout the year. The average dynamics for all of the plant species investigated included an increase in yeast numbers during spring and summer with the maximum in late autumn and early winter. The character of the yeasts' dynamics depends on the ecological characteristics of the plants and the duration of the ontogenesis of their leaves and flowers. Three types of dynamics of epiphytic yeasts were revealed: year-round with an increase in autumn-winter, year-round without visible changes, and seasonal with a terminal increase for annual plants.     

Seroepidemiological characterization of virus hepatitis in the Republic of Armenia

The survey of the population immunological structure with respect to parenteral hepatitis showed awide circulation of hepatitis B (HB) and hepatitis C (HC) viruses among the adult population of Armenia. During the 5 year period of observation the number of persons having antibodies to HC virus increased 2.7-fold. High occurrence of antibodies to HBsAg of HB virus among the healthy population in 2002 (12.0%) in comparison with 1997 (5.4%) reflected a decreased infection rate with HB virus as well. Antibodies to hepatitis A (HA) virus were isolated, on the average, in 64 % of persons. Simultaneously with a decrease in the proportion of HA cases an increased number of HC patients was registered. No circulation of hepatitis E virus was detected. A high percentage of hepatitis cases of mixed etiology was established, as well as an increased number of combined parenteral hepatitis cases was registered (57.1%).     

Epidemiologic analysis morbidity with meningococcal infections in the USSR]

The authors present the analysis of the incidence of epidemic cerebrospinal meningitis in the USSR from 1937 to 1974, and of meningococcus infection from 1965 to 1974. A rise of the meningococcus infection incidence from 1969 to 1974 was recorded 28 years after the elevation of 1940-1942 and was 1.5 times below this latter rise. The rise in 1969-1974 was characterized by marked signs peculiar to the infection with the droplet transmission mechanism; among those who contracted the disease prevalence was seen among children aged under 14 years (63-72%). A marked affection of juveniles was noted. Three types of the dynamic of the meningococcus infection incidence in the republics located in different climatic-geographical zones of the USSR were noted: slow, gradual increase of the level, interrupted and explosive. Such character was determined in the dynamics of the seasonal elevations of morbidity. Antiepidemic measures including a complex of nonspecific measures could not be assessed as sufficiently effective. This finds reflection in the natural course of the epidemic process of the meningococcus infection which remains uncontrolled. From the patients with generalized form of the disease meningococci of group A were isolated in 80-100% of cases, from the number of those typed. The group-specific reference of the nasopharyngeal strains depended on the epidemic situation: strains of serological group A prevailed at the period of the morbidity elevation, and other serological groups (particularly of C and B) increased at its decline.