The characteristics of an outbreak of non-A, non-B hepatitis with a fecal-oral mechanism of the transmission of the causative agent in Osh Province, the Kirghiz SSR

The results of epidemiological, clinical and laboratory studies revealed that the sharp rise of morbidity in viral hepatitides in Osh Province, the Kirghiz SSR in autumn 1987 was caused by hepatitis non A, non B virus with fecal-oral transmission. At this period the results of the enzyme immunoassay showed the absence of the markers of hepatitides A, B and Delta in 72.2% of viral hepatitis patients. Hepatitis non A, non B occurred only in 2.4% of viral hepatitis patients of preschool age (of these, 83.3% had hepatitis A) and was diagnosed in autumn 1987 in 50% of the patients aged 7-14 years and in 97.4% of the patients aged 15-29 years (in the latter age group 95-98% of the patients had IgG to hepatitis A virus in their blood). The appearance of the outbreak of the above-mentioned infection in Kirghizia is linked with the water route of the transmission of the infective agent. The epidemiological and clinical signs, characteristic of fecal-oral hepatitis non A, non B in Kirghizia, were not different from those registered earlier in other republics of the Central Asia and could be used for the identification of this infection.     

Family incidence of type B hepatitis

Family incidence of HBsAg-positive viral hepatitis was confirmed to be high. In 499 families with a type B viral hepatitis patient, type B viral hepatitis morbidity among 1116 contacts amounted to 2.24% within 6 months of the primary patients' hospitalization (being 188.2 times higher than semiannual morbidity of the population of the Czech Socialist Republic, CSR) and the prevalence of HBsAg amounted to 8.96% (being 22.4 times higher than among the population of CSR). On deducting positive findings at first blood samplings, which at least partially eliminated individuals who could themselves have been the source of infection for the first patient in each family, the rate for contact cases equalled 0.70% (58.8 times higher morbidity than among the population) and the rate for HBsAg prevalence equalled 2.50% (6.25 times higher than among the population). Among 917 members of 335 families where a case of HBsAg-negative viral hepatitis occured, 0.32% developed HBsAg-positive viral hepatitis within 6 months (26.8 times higher morbidity than population morbidity) and the HBsAg prevalence was 2.94% (7.35 greater than among the population). On deducting the first positive findings no clinical illness remained and HBsAg prevalence equalle 0.98% (2.45 times higher than among the population). The highest HBsAg prevalence was found among contacts aged 0-5 years (17.09% for the whole period, 3.41% after deducting first positive findings) and 40 years and over (10.82% and 3.39%, respectively). Type B viral hepatitis morbidity was again highest in the age groups of 0-5 years (5.12%) and 40 years and over (2.54%) for the whole period. On deducting first positive findings, the 40+ years group displayed the highest morbidity (1.27%), whereas the 0-5 years group displayed zero morbidity. Disclosure of the mechanisms of nonparenteral or inapparently parenteral transmission specific for family environments would be important for the prospect of introducing adequate measures to limit or prevent the spread of type B viral hepatitis.     

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%.     

Tick-borne encephalitis in the Estonian SSR

The foci of tick-borne encephalitis (TBE) of 2 types, differing in their morbidity rates, the character of their immunological structures, the species composition of carrier mites and their capacity for TBE virus carriership, have been shown to exist in Estonia. TBE morbidity is characterized by 4- to 5-year cycles, the overwhelming majority of TBE cases being registered in the area of the joint habitat of both species of mites. During the epidemic season 2 peaks of morbidity rise are registered, which corresponds to peaks in the number of mites in nature. Different epidemic importance of 2 species of carrier mites in TBE morbidity in Estonia has been shown.     

Morbidity and mortality in acute viral hepatitides in a hyperendemic region. The role of viral hepatitis E

Official annual statistical data on morbidity in acute viral hepatitides (AVH), including the number of lethal cases, for 1985-1995 were analyzed. Mortality rates per 100,000 of the population at the period of 11 years were calculated for different age groups, sex and the place of residence. 396 and 99 patients were examined for the presence of serological markers of hepatitides A, B and E, respectively, at the periods of epidemic rises in morbidity and satisfactory epidemic situation. In the course of 11 years AVH caused the death of 22,405 persons. In 1985-1987 the average mortality level (ML) reached 12.3-17.8 per 100,000 of the population (with morbidity being 1,200-1,400 and was essentially higher among the rural population in comparison with the urban population. During these years the highest ML, was registered among children aged 0-2 years (190-50 per 100,000) and, among adults, mainly among women aged 20-29 years (21.4-19.6 per 100,000). During the years when the epidemic of AVH was absent, ML among these groups was essentially lower: 40-20 among children aged 0-2 years and 4-5 among women aged 20-29 years. In 1987 in the Fergana Valley hepatitis E was detected in 72.2% of all examined patients, and in the southern areas of the country in 68.7%. A sharp rise on mortality among women of the productive age at the period of the epidemic rise of AVH morbidity in the endemic region indicated that this epidemic was linked with hepatitis E. High ML among young children may be indicative of a highly unfavorable course of hepatitis E in the group of infants, which had never been registered before. This newly established regularity may be used for the retrospective diagnostics of the outbreak of hepatitis E.     

Epidemic process of pertussis in Moscow

Materials reflecting the dynamics of pertussis morbidity during the period of 1958 - 2003 under the conditions of prolonged mass immunization of the child population with adsorbed DPT vaccine are presented. The planned vaccination of children led to the decrease of pertussis morbidity during the first 10 years, but groundless abstentions from vaccination during the 1980s - 1990s contributed to a sharp rise in morbidity among children of younger age groups. During the recent four years a rise in pertussis morbidity was registered in 2000 (71.79 per 100,000 of the population), followed by the most significant for the last 20 years drop in morbidity in 2002--down to 9.89. But in 2003 the growth of morbidity was again registered (38.67). Recently periodic rises and drops in morbidity occurred simultaneously with the increased coverage of children of younger age groups with vaccination. In recent years changes in the age structure of patients were observed: the specific proportion of school children increased (in 2003 morbidity rates in children aged 6 - 10 years were 288.6 - 270.7), simultaneously high morbidity among children aged up to one year (274.9) was registered. The specific proportion of pertussis-affected children aged above 7 years reached 65%. From the late 1990s until present in 87.1% of cases strains of serotype 1.0.3 prevailed in the population of B. pertussis strains. But in recent years the circulation of strains 1.2.3, spread in the prevaccination period and having toxicity similar to that of strains of serotype 1.0.3, while exceeding them in virulence, in sufficiently high proportion (7.0% in 2002) was noted. This was indicative of the possibility of the unfavorable development of the epidemic process of pertussis infection.     

Role of carriers of the hepatitis B surface antigen as possible sources of infection in children's collectives

The complex clinico-epidemiological and laboratory surveys of the children and the staff in 71 institutions for children of preschool age were made at the period of increased viral hepatitis morbidity in these institutions, and the dynamic observations of 11 children's institutions having children with prolonged HBs-antigenemia were carried out. In the foci of viral hepatitis the level of antigenemia in the children and the staff exceeded (p less than 0.01) that in the control group. The dynamic observations (lasting up to 6 years) of the groups containing HBsAg-carriers revealed that 6 children, previously HBsAg-negative, showed a short-term HBs-antigenemia in the absence of any evidence of the parenteral (instrumental) route of infection. This fact indicates that the role of HBsAg-carriers as the possible sources contributing to the transfer of hepatitis B through everyday contacts in children's institutions cannot be ruled out. Periodic clinico-epidemiological and laboratory surveys of groups with HBsAg-carriers are recommended.     

The leading routes and factors in the transmission of the causative agent of campylobacteriosis under current conditions]

Epidemiological investigations carried out at the foci of Campylobacter infection in Moscow and the Moscow region in 1987-1990 demonstrated that Campylobacter infection was recently registered as sporadic cases in a few foci. The alimentary route of the transmission of this infection was the main factor of its spread. A high role of everyday contacts in the spread of this infection was noted. The possibility for outbreaks and sporadic cases of Campylobacter infection to be masked by very frequently occurring associations of these bacteria is discussed.     

Prevention and control of HIV infection in the Osh region of the Kyrgyz Republic

A total of 178 cases of HIV infection were diagnosed in the Osh region of the Kyrgyz Republic for January 1, 2003, the intensity of the prevalence of HIV infection being 14.5 per 100,000 of the population with this figure for the whole republic being equal to 5.9. In the dynamics of the HIV infection epidemic two periods were detected. During the first 3 years (1998-2000) a few individual imported cases of HIV infection were registered in the region. During the last 2 years (2001-2002) 98.8% of all cases of HIV infection registered in the region, as well as the presence of an epidemic outbreak among injection drug users (IDU), were detected. The risk factors of getting HIV infection were the intravenous use of drugs and a low level of information among young people concerning the routes of transmission of this infection and means of protection from HIV/AIDS: the promotion of healthy life style among young people, the introduction of the programs of "harm reduction" among IDU and the rules of safe sex.     

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.     

Spread of viral hepatitis in organized children's collectives and the methods for its early diagnosis]

The authors present the results of observations over 407 children aged from 2 months to 16 years from the foci of viral hepatitis in children's collective bodies. During the quarantine a determination was made in children of the glutamic-pyroracemic, glutamic-oxalic transaminases (GPT and GOT, respectively) and of the hepatitis B antigen (HBAg). A necessity of using the enzymatic tests for the purpose of early diagnosis of viral hepatitis was shown, since 84% of the cases developing in the next focus coursed as an unicteric form without any markked clinical signs; HBAg was revealed in 6.1% of the children examined. A complex examination of the personnel and of the persons who came in contact with the patients with viral hepatitis showed the ways of spread of hepatitis B in a collective body; it was found that the viral hepatitis B infection took place both by parenteral and enteral routes. The expediency of active observation over the children, recipients of blood and plasma, with determination in them of the activity of the enzymes and HBAg for early diagnosis of parenteral infection was substantiated. It was also shown that the incidence of the unicteric forms of viral hepatitis in a focus of infection depended not on the periods of gamma-globulin administration but on the age of children who contracted the infection. Thus, the prevalence of the unicteric forms of the disease over the icteric ones in children under 3 years of age was more pronounced than in older children.     

Viral hepatitis in different population groups of Republic of Sakha (Iakutia)

A survey for the presence of markers of viral hepatitis B, delta, C and E among different groups of the population of the arctic and agricultural zones of the Republic of Sakha (Yakutia), as well as in Yakutsk, was carried out. The survey revealed that viral hepatitides with the parenteral mechanism of the transmission of infective agents were widely spread among the population. In the arctic zone HBsAg was detected in persons aged 20 years and older in 10.8-17.1% of cases. On the average, in the arctic zone antibodies to virus delta were detected in 2.4% of cases. In different regions of the agricultural zone the detection rate of HBsAg was also high (10.4-23.8%). In the Namsk and Vilyui regions delta infection was registered among adolescents (15-19 years of age) in 8.7 and 22.4% of cases respectively. In the Mountainous region anti-delta antibodies were detected among persons aged 20 years and older in 31% of cases. The survey showed the presence of considerable differences in the detection rate of the markers of hepatitis B, depending on the ethnic origin of the examined patients. Similar tendencies were found to exist with respect to delta infection.     

Specific features of the typhoid fever epidemic process in organized collective

During the chronic water epidemic of typhoid fever in Tajikistan in 1996-1997 specific features of the epidemic process dynamics in groups of servicemen were studied in several cities. The infective agent was proved to be transmitted by the alimentary route and through everyday contacts, the water route of transmission playing the most important role. The early clinical and epidemiological signs of the water outbreak of typhoid fever and the risk factors were established. The clinical and epidemiological aspects of vaccination were analyzed.     

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.     

Problems of the epidemiology of viral hepatitis in Ryazan Province

The analysis of some features of the course of the epidemic process of viral hepatitis on the territory of the Ryazan region is presented. Periodic rises and falls in viral hepatitis morbidity, varying in their regularity (4-6 years), have been registered in the region. The general level and the seasonal distribution of viral hepatitis morbidity are determined by the morbidity rate among children, the increase in the proportion of children of senior school age being observed in recent years.     

Characteristics of brucellosis epidemiology in children in the Kazakh SSR

The analysis of brucellosis morbidity among children in the Kazakh SSR for the last 10 years revealed the following facts. The highest morbidity rate among children was registered in zones with developed sheep breeding. Privately owned agricultural animals, mainly small cattle, proved to be the main source of infection, transferred in most cases through contacts. contacts. The occurrence of brucellosis among children was found to be directly related to their age. Most of the sick children were boys. The pronounced seasonal character of brucellosis morbidity, falling mainly on spring and summer, was observed. In surveying the population for brucellosis the use of a complex of sero-allergic tests permitted the detection of a great number of infected subjects. Most sick children showed a typical picture of acute brucellosis. Treatment resulted in their clinical convalescence.,     

Hepatitis C virus. A review.

Hepatitis C virus has been shown to be responsible for most cases of posttransfusion hepatitis, as well as for sporadic non-A, non-B viral hepatitis. Hepatitis C virus has also been implicated in the development of primary hepatocellular carcinoma, autoimmune hepatitis, and fulminant viral hepatitis. Although the role of the parenteral transmission of hepatitis C virus is well established, its route of transmission in cases of sporadic infection remains unclear. Sexual transmission is suspected but not confirmed. Recent work regarding treatment has shown interferon alfa to be effective, but the discontinuation of therapy is associated with a 50% relapse rate.     

The dynamics of the course of HIV infection in patients with concomitant sexually transmitted disease morbidity and viral hepatitides detected in Saint Petersburg in 1997-1998

During the recent 2 years growth in the number of cases of HIV infection, exceeding 1.2-fold the number of cases detected during the preceding 9 years, was registered in St. Petersburg. In the structure of patients with detected HIV infection injecting drug users prevailed. Among 124 patients with detected HIV infection 28.2% and 46.8% had, respectively, concomitant sexually transmitted diseases (STD) and virus hepatitides (VH). Due to preventive and antiepidemic measures the STD and VH morbidity decreased in all groups of HIV-infected patients under study.     

Epidemiological and immunological monitoring of tetanus in Georgia (Republic)

During the period of 1961-1990 the regular immunological and epidemiological monitoring of tetanus was carried out. At the prevaccination period (1937-1960) 140 cases of tetanus were registered, 77 patients died (morbidity rate being 0.97-0.11 per 100,000 of the population with mortality rate equal to 55.6%). At the period of mass vaccinal prophylaxis (1960-1990) 56 cases were registered and 27 patients died (the corresponding values: 0.09-0.11 with 48.2% mortality). In 1981-1990 altogether 53,213 vaccinees were examined. 4,864 vaccinees (8.9%) proved to be seronegative and 43,615 vaccinees (81.9%) were found to have protective antibody titers. 4,220 pregnant women were examined; 476 women (11.2%) proved to be seronegative and 3,576 women (84.3%) were found to have protective antibody titers. Timely specific prophylaxis proved to be the only way for decreasing tetanus morbidity.     

Measles morbidity among children inoculated against this infection

In the serological survey of 2009 children immunized against measles 285 children (14.2%) were found to be seronegative to this infection in the hemagglutination inhibition test with 4 hemagglutinating units of the antigen. Among 1724 immunized children showing positive response to vaccination and placed under dynamic observation for 11 years, 2 cases of measles were registered. At the same time, in the dynamic observation of 111 seronegative children 66 measles cases (59.5%) were registered during the above period, while among 169 children, also seronegative, but receiving booster immunization against measles, morbidity rate was only 1.2%. In some vaccinees the decrease of postvaccinal immunity to seronegative values was observed, but such decrease had no essential influence on the morbidity level among the vaccines. The increase of measles morbidity among schoolchildren immunized against this infection was due not to the decrease of their postvaccinal immunity, but to their concentration in schools and to their more intensive contacts with the sources of infection in comparison with children of preschool age.