Introduction

The history of the spread of infectious disease in the countries of the former Soviet Union is closely related to the political and economic conditions. The topic can be characterised within geographic and time frames. The Soviet Union experienced isolation from the rest of the world during approximately 70 years of its history; most information was kept secret, data on infectious diseases were considered confidential and not available to the scientific community. The situation changed shortly after the breakdown of the Soviet Union. The statistical data available are, however, fragmentary and not consistent from publication to publication.

Transmission of infectious diseases during the past century depended on social, economic and political processes. The history of the Soviet Union provides good examples of how political and economic change in a country precedes the emergence of infectious diseases. Any crisis in a society brings socio-economic change, including low income, unemployment, crowded housing and improper nutrition. Socio-economic change is associated with a range of health problems including impairment of the immune system leading to increased susceptibility to infectious diseases. Behavioural changes and reluctance to use condoms gives excessive exposure to infectious agents. Problems in the health care system are caused by insufficient financial funding and include shortages of essential drugs, delayed diagnosis, inadequate vaccination and treatment. All these factors make patients infected for prolonged periods of time, increase exposure of susceptible individuals to infectious agents, hence providing the necessary conditions for the emergence of infectious diseases.

Regular emergence of infectious diseases in a particular area provides an opportunity to analyse causation. The epidemic peaks in the incidence of infectious diseases evidently occurred after political and economic changes during the past century. The first wave of epidemics came shortly after the October Revolution in 1917; the next one was caused by the consequences of the Second World War. In the early 1990s, an increase in the incidence of infectious diseases started with the disintegration of the Soviet Union and was accelerated by the economic crisis in August 1998.

During Soviet times, the country comprised 15 socialistic republics that became independent states in 1991. Five of them (Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan) are located in the Central Asia. Armenia, Azerbaijan and Georgia in the Caucasus, Ukraine, Moldova and Belarus are in the west, while Estonia, Latvia and Lithuania are in the Baltic region. Russia is one of the world’s largest countries with a population of approximately 145 million and an area of 17 million km², spanning seven geographic zones, ten time zones and three climatic zones. This diversity, in addition to socio-economic change, substantially influences epidemiological indicators of infectious disease in this country.

Socio-economic changes and the history of infectious disease control in the Soviet Union

The modern history of Russia and the new independent states may be divided into two periods: the Soviet era and the post-Soviet era. The Soviet era began in 1917 with the October Revolution and the Communist Party founding the Union of Soviet Socialist Republics. This political change resulted in crises in the economy and in the standard of living and created conditions for the spread of infectious diseases. At the time, about 2 million people, roughly 2 % of the population, died from tuberculosis⁷. Syphilis and diphtheria also lead to high morbidity.

The post-revolution Soviet Union started rebuilding its industry and agriculture. A growing economy improved socio-economic conditions and people were provided with adequate housing and proper nutrition. Adequate housing decreased the number of persons sharing the same room, hence reducing the risk of exposure to infections agents. Improved nutritional status strengthened the immune system’s ability to fight back infection.

The Soviet government showed great commitment to a reorganisation of health and medical services, which were available to everyone free of charge. It provided the necessary funding for infectious disease control, organised a specialised system consisting of centralised clinics or dispensaries, opened departments for infectious diseases in medical universities, designed vaccination strategies and programmes, and organised epidemiological monitoring of infectious diseases.

In 1985, Soviet economy and society experienced a dramatic change when Mikhail Gorbachev introduced the policy of glasnost and perestroika. His initiatives released forces that by December 1991 had split the USSR up into 15 independent states. Since then, Russia and the other states have struggled to build a democratic political system and a market economy. Political changes resulted in economic crises that threatened living standards and made for the spread of infectious diseases; 20 % of urban families lived in crowded accommodation, as the state system of housing distribution broke down and people had to afford their own accommodation³. Young singles usually lived in crowded hostels or student dormitories; young married couples with their parents. Because of the economic crises and declining purchasing power, the average diet was insufficiently balanced. Vegetables were for the most part only available in rural areas, fruit was not an important element of the diet, and the consumption of meat decreased³.

In the early years of the decade, a crisis developed in the health care system because of insufficient government funding, falling numbers of medical personnel, and lack of equipment and technology. Medical establishments were not supplied with all essential drugs because the Soviet system of drug distribution had broken down, with no good alternative in its place. In addition, the health care system did not run educational programmes for the population, for example on hygiene and a proper diet. All these factors were accompanied by mass media campaigns criticising the health care system, warning against adverse effects of vaccination and drugs, leading to people loosing faith in public medicine. At this time the government established an obligatory health insurance system. Several private clinics were organised to provide treatment on an anonymous basis and private pharmacies sold drugs, including antibiotics, without a doctor’s prescription.

Re-emergence of infectious diseases in the former Soviet Union

During the past few years, Russia and other new states have experienced the re-emergence of old diseases such as tuberculosis, diphtheria, syphilis, hepatitis B, and the emergence of new diseases such as HIV infection. The re-emergence of the old diseases was accompanied by genetic changes in pathogens leading to drug resistance and increased virulence⁸. Infectious diseases occur as a result of an interaction between the human host and the micro organism. Social and economic factors can decrease the host’s ability to fight back the pathogen while at the same time increased virulence and drug resistance make progression to active disease more likely and patients remain infectious for a prolonged period of time. Antibiotic resistance increased when drugs became available without a prescription It was combined with a massive shortage of drugs in clinics, especially those in the prison system, and frequent self-medication. Self-medication often included inappropriate selection of drugs, leading to insufficient treatment and emergence of drug-resistant micro-organisms. That is why these diseases have become the most urgent threat to public health⁸.

Diphtheria

Diphtheria is normally a disease of childhood, but the history of the Soviet Union shows that a non-immune adult population can be affected. Diphtheria was a highly endemic disease in the early 20th century (600/100 000)¹⁶. The decrease in the incidence of diphtheria in the Soviet Union in the early 1920s was associated with improved living standards and the introduction of vaccination in some areas. After the first fall in incidence (100/100 000), there were periodic waves of epidemics. It is difficult to identify the factors that governed diphtheria periodicity between 1930 and 1950. A universal childhood immunization campaign began in 1958; by 1963 the incidence was down dramatically (25/100 000). The disease was successfully controlled during 30 years by a good vaccination programme¹⁶.

In early 1990s, diphtheria started to re-emerge in the countries of the former Soviet Union. For the first time in the history of infectious diseases, most cases of diphtheria occurred in adults. In 1994, the diphtheria epidemic was reported from all states except Estonia, as most of its adult population had been vaccinated between 1985 and 1987. The cases were concentrated in Russia (26.41/100 000), though a similar epidemiological trend was observed in the countries of Central Asia (5.41/100 000), the Caucasus (7.02/100 000), the Western countries (5.35/100 000), and the Baltic countries (3.69/100 000)¹⁶.

Several factors might explain the emergence of diphtheria in the post Soviet period. Changes in the immunization schedule during this period resulted in less intensive vaccination of children. The number of conditions considered temporary or permanent contraindications to vaccination was increased. In addition, the mass media made people fear adverse reactions to vaccination. This resulted in a drop of vaccination coverage and, hence, inadequate vaccination. Re-emergence of diphtheria was also associated with a biological change in the pathogen: a change in the predominant circulating biotype from gravis to mitis was documented¹⁶. The peak of the epidemic came in 1995, then a massive vaccination campaign was implemented and the incidence started to decrease steadily, reaching its initial level in the late 1990s.

Sexually transmitted diseases

The system for the control of sexually transmitted diseases (STD) in the Soviet period was free of charge but lacked confidentiality. Shortly after the revolution a committee for the control of venereal diseases was set up. In 1921 it started to develop a network of centralised and specialised dispensaries for the treatment of STD on an inpatient basis¹³. The official opinion on STD was negative, they were held to be morally undesirable. Persons diagnosed with syphilis and gonorrhoea were seen as having a morally corrupted capitalistic behaviour. Under criminal law, persons found to be infected and who refused treatment or who had sex after being notified about the infection, could be prosecuted. Patients and contacts were prevented from accessing a variety of municipal facilities, taking up new jobs or go abroad until they were cured. The system had a good screening for syphilis and gonorrhoea organised for certain occupational groups, including cooks, medical personnel, school and hotel staff, patients admitted to hospitals, and pregnant women. Doctors were under legal obligation to report all cases by name and address¹³.

After the glasnost period and the disintegration of the Soviet Union, historical data describing the occurrence of syphilis have become available. The notification rate for syphilis in 1921 was 550/100 000 population. Introduction of penicillin and STD control helped to reduce it to 2.45/100 000 by 1963; it reached a new peak of approximately 30 in the mid-1970s (30/100 000) and declined again in the late 1980s (2/100 000)¹².

After the break-up of the Soviet Union, there were dramatic changes in STD control; first, because of lower government funding, and secondly because many doctors began to move towards the idea that STD control should be addressed by combining social education and by means of information through the primary health care system¹³. The contemporary STD service is based on voluntary attendance and partner notification. It became very clear that many people preferred to be treated in the private sector in order to avoid the stigma of STD. In response to these changes, the Russian Ministry of Health issued new instructions for screening, diagnosis, contact tracing, licensing of private practitioners, social care, providing medical supplies and for research¹³.

The incidence of syphilis has increased sharply in the states of the former Soviet Union since the early 1990s, in 1996 reaching the level of 263/100 000¹². Approximately equal numbers of men and women were affected. The incidence among young people was significantly higher. For example, the notification rare of syphilis among women aged 18–19 exceeds 1/100. The epidemical situation in the western countries (Belarus 210/100 000, Moldova 200/100 000 and Ukraine 144/100 000) and Central Asia (Kazakhstan 231/100 000, Kyrgyzstan 137/100 000) was similar in the mid-1990s; in 1996 it was more favourable in the Baltic states (Latvia 117/100 000, Lithuania 99/100 00; and Estonia 70/100 000)¹².

The situation in the countries implied changing patterns of sexual behaviour², partly because of the opportunity of going abroad after the complete isolation during the Soviet era. This increased possibility of having sexual contacts and made sexually oriented products widely available¹³. A rapid decline in the age at first sexual intercourse has been described in Russia and the other new countries. It is also believed that adolescent prostitution has increased. Low social background made people reluctant to use condoms. It is documented that between 1985 and 1995 there was an increase in syphilis among the unemployed from 18 % to 50.4 %. The health care system had problems tracing contacts because of private clinics that provided treatment on an anonymous basis without reporting cases¹³. The incidence of syphilis and other sexually transmitted diseases in the region may be underestimated.

Hepatitis B

Rates of hepatitis B in Russia increased steadily, reaching peaks in 1996 (35.8/100 000) and 1999 (43.3/100 000)⁸. The reasons are the same as those for STDs. They include changes in sexual behaviour, low social background, frequent change of partners, and reluctance to use condoms². Moreover, increasing intravenous drug abuse has been documented. especially among young people. Along with higher incidence. lower average age at infection was documented. In 1994. the majority of patients were about 24 years of age; in 1999 it was down to 22 years¹. It is an interesting fact that men contracted hepatitis B at a significantly younger age than women. Men were primarily infected by other men through shared infected syringes and homosexual intercourse, while women were infected by men through heterosexual intercourse. Infection among women can be also due to injection drug use, but to a smaller extent than infection among men¹. The health care system did not always provide disposable syringes for treatment. Some cases resulted from transfusion of infected blood. Children born from mothers with hepatitis B were at great risk to be infected and become chronic carriers².

HIV infection

HIV is a new emerging infection in the region. A mass HIV screening programme was introduced in 1987, which is towards the end of Soviet period⁴. It was targeted at low risk groups: pregnant women, blood donors, medical personnel, and hospital patients, foreigners arriving and planning to stay in the country for an extended period of time, and persons that had spent more than one year abroad. HIV was diagnosed in the Soviet Union early in 1987; the first infected person had been infected in Africa through sexual contact. In 1989, an outbreak of nosocomial HIV infections occurred among 250 children in the southern Russian republic of Kalmykia. It was followed by an epidemic among adults; around 40 % of the cases were caused by homosexual transmission⁴.

From 1990 to 1999, the number of HIV-infected persons in Russia increased dramatically, from 95 in 1990 to 10 900 in 1999⁸. Official statistics on HIV reflects only 10 % of the actual number of infected persons. The majority (60 %) of HIV-infected persons were intravenous drug abusers. The highest incidence was found in the big central cities and sea ports of Russia. The city of Kaliningrad, located in the west part of the country and isolated geographically from Russia by the Baltic states, was the most affected region⁴. Other cities with rapidly spreading HIV epidemics are Krasnoyarsk, Nizhniy-Novgorod, Rostov, Tver and Saratov. Smaller numbers were reported from several other cities and regions, including Siberia and the far north.

The former Soviet Union has the fastest growing HIV epidemic in the world. HIV prevalence varies widely in Ukraine, Belarus, and Moldova. In Ukraine, only 40 to 80 new cases were registered each year from 1988 to 1994⁴. These were mainly among foreigners infected through sexual contacts. In March and April 1995, more than 1000 intravenous drug users in two main cities in Ukraine were found to be HIV positive. A year later, HIV infection among intravenous drug users was reported from all 25 regional centres in Ukraine. The total number of diagnosed cases rose to more than 25 000 in 1997. Few HIV infections had been reported in Belarus until May 1996, when mass screening of intravenous drug users revealed that 632 (50 % of those tested) were infected by HIV. By the end of 1997, the total number of HIV infections had increased to 1800 cases⁴. HIV is less prevalent in Baltic states, in particular in Lithuania, and in the states of Caucasus and central Asia⁵.

Several factors are associated with the HIV epidemic^{2, 4}. They include intravenous drug abuse becoming prevalent among young people. Sharing of needles was very common among drug abusers in Moscow, Kaliningrad and Poltava. HIV infection might also result from the process of the preparing the drug for injection. There are reports from several cities, including Moscow and Kaliningrad, which indicate that blood was added to the drug before injection⁴ because of a belief that the blood cells neutralise toxic reagents. Change of sexual behaviour patterns, low social background and reluctance to use condoms were other important contributing factors. Some data suggested spread of HIV infection among pregnant women, children born from HIV positive mothers, and blood donors. Blood donation is based on a voluntary system, though donors receive incentives such as payment, free food for the day, and two additional days off work. The HIV epidemic is also fuelled by the policy of distributing HIV-infected prisoners around the country. Until recently, all HIV-infected prisoners were kept in one prison, now they are allocated to different prisons around the country. Intravenous drug use has increased among prisoners; HIV is spreading in the prisons through shared infected needles and unprotected sex. Very few prison health services offer needle exchange and condoms, which would reduce the risk of infection. Migration from highly endemic countries also fuels the current epidemic.

Tuberculosis

The centralised dispensary system for tuberculosis prevention and treatment was introduced in the Soviet Union in 1918 and streptomycin and PAS has been used for treatment of tuberculosis since the 1940s. Isoniazid, cycloserine and thiacetazone were introduced in the 1960s; rifampin was available from the early 1970s. As a result of a good control programme and the introduction of specific antibiotics, the incidence of tuberculosis fell steadily from 119 per 100 000 inhabitants in 1965 to 34 per 100 000 in 1991. From 1991, however, the incidence started to rise sharply, reaching 90.3 per 100 000 in 2000^{9, 14}.

In Estonia, after a decline in tuberculosis incidence from 417/100 000 in 1953 to 26/100 000 in 1992, there was a steadily increasing incidence, reaching 52/100000 in 1999⁶, accompanied by an increase in drug-resistant tuberculosis, particularly multidrug-resistant (MDR) tuberculosis, that is resistance to rifampin and isoniazid¹⁷. In 1998, MDR tuberculosis accounted for 14 % of new pulmonary cases. The majority (87.5 %) of these patients were infected by a highly virulent strain of the W-Beijing genotype⁶.

The incidence of tuberculosis in Latvia has followed a similar trend, up from 1991 to a rate of 74/100 000 in 1998¹⁵, since then remaining at about the same level. MDR was found in 8.6 % of new cases and in 34.5 % of all tuberculosis patients in 2000. The most dramatic increase has been observed in Georgia, where reported notification rates increased from 29.8/100 000 in 1989 to 194.7/100 000 in 1996¹¹.

Prison systems are known to create emergence of tuberculosis. Epidemiological indicators in the prison system are several times higher than in the community at large; there is, for instance, an extremely high incidence of tuberculosis (4667/100 000) in the prison system of Azerbaijan¹⁰.

The increasing incidence of tuberculosis has been attributed to social changes after the political and economic crisis. The health services had less medical personnel and lacked equipment, technology, funding and of supplies of all essential drugs. The treatment regimens for tuberculosis were individual and usually consisted of three drugs, including second-line medication. Severely ill patients were prescribed four drugs. No supervision of treatment was provided; this allowed patients to take their drugs on an irregular basis. Interrupted treatment and inadequate regimens increased the infectious period for many patients and the probability of healthy individuals being exposed to and infected by tuberculosis. Up until the 1990s, all patients with tuberculosis were hospitalised for the entire duration of treatment, hence there were good opportunities for preventing interruption of treatment. However, the re-emergence of tuberculosis resulted in a lack of resources and unavailability of hospitalisation for all patients.

The epidemic was also fuelled by the situation in the prison system. Tuberculosis originating in the prison systems of the former Soviet Union affected inmates, personnel, and also those outside the walls. Nowadays, tuberculosis has new features: increased incidence of antibiotic resistance and the emergence of a new virulent genotype called W-Beijing; it causes high morbidity and mortality from tuberculosis.

Conclusion

The history of the Soviet Union provides strong evidence to the effect that economic, social and political change made for the emergence of infectious diseases. Political, economic and social transitions have brought changes in the health situation of the population, causing an emergence of new and reemergence of old infectious diseases. The consequences of changes and the extent of infectious disease spread vary from country to country. Infectious diseases have similar epidemiological patterns over the past decades in the countries of the former Soviet Union. The threat of these diseases is well recognised, and improved social and economic conditions in these countries as well as research aimed at analysing new biological features of pathogens will allow us to improve the situation and combat infectious diseases.