Polio. Pernicious arrogance

2024 Author: Seth Attwood | [email protected]. Last modified: 2023-12-16 15:55

One of the most global and costly initiatives of the World Health Organization (WHO) and health officials of all countries for many years has been the worldwide fight to eradicate the human polio virus. Today this struggle is as far from its goal as it was decades ago.

Opponents and supporters of vaccination have been exchanging arguments about the harmfulness / usefulness of vaccinations in general for more than two hundred years. In this article, we will talk about one specific disease, about vaccines against it and the history of medical and paramedical manipulations around it. This disease is human polio.

For further understanding, biological and medical details are indispensable. Hereinafter, only official, "mainstream" medical positions will be presented, unless otherwise stated. So, poliomyelitis (polio (Greek) - gray, myelos - brain) is an acute viral infection that can affect the nervous system (gray matter of the spinal cord) with the development of peripheral paralysis. The causative agent is an RNA-containing virus of the Picomaviridae family of the Enterovirus genus. There are 3 known serotypes of the virus. The pathogen can affect the motor neurons of the gray matter of the spinal cord and the nucleus of the motor cranial nerves. When 40-70% of motoneurons are destroyed, paresis occurs, over 75% - paralysis.

The only known reservoir and source of infection is a person (sick or carrier). Most cases are asymptomatic (it is unclear from the outside that the person is sick). The infection is spread by the fecal-oral route, through direct or indirect contact with feces. Diseases are recorded at any age, but more often in children under 5 years of age. In young children, observe the so-called. an abortive form (more than 90% of all cases), characterized by a mild course and the absence of damage to the nervous system. The disease develops 3-5 days after contact and proceeds with a slight increase in body temperature, malaise, weakness, headache, vomiting, sore throat. Recovery occurs in 24-72 hours. In 1% of cases, a more severe, but also not paralytic form develops - a temporary inflammation of the meninges (polyomeningitis)

In the paralytic form, the incubation period is 7-21 days (in patients with immunodeficiency - up to 28 days), followed by a preparative period (1-6 days), which may be absent. At this moment, intoxication (fever, headache, weakness, drowsiness), catarrhal inflammation of the upper respiratory tract, diarrhea, vomiting appear. Then comes the paralytic period (1-3 days). It manifests itself in low muscle tone (hypotension), decreased or absent reflexes of the affected muscles and their rapidly developing atrophy - this symptomatology is called acute flaccid paralysis (AFP, in English - AFP). The paralytic form from the first days is difficult, in 30-35% there is a so-called. bulbar form (with damage to the muscles responsible for breathing). In fact, the severity of the disease is determined by respiratory failure. And finally, there comes a period during which the affected muscles recover - within a few days. In severe cases, recovery can take several months or even years; sometimes, full recovery does not occur. The ratio of the number of paralytic and non-paralytic forms of poliomyelitis in epidemics of the XX century. in developed countries according to various sources - from 0.1% to 0.5% (1: 200-1: 1000). The most at risk of developing paralytic poliomyelitis are: patients with immune deficiencies, malnourished and debilitated children, and pregnant women who are not immune to poliovirus.

An important point needs to be made - since the discovery of poliovirus in 1909and until the mid-20th century, any acute flaccid paralysis (AFP) was considered polio. Paradoxically, polio paralysis is considered the only infectious disease, the incidence of which increased sharply in the late 19th and early 20th centuries, and the main epidemics fell on the 30s, 40s, and 50s of the 20th century. At the same time, in underdeveloped countries, the incidence of AFP remained low, even single. There were, for example, outbreaks of paralytic polio among American troops in China, Japan and the Philippines, while local children and adults were not sick. In 1954, the US military in the Philippines (including families) had 246 cases of paralysis, 52 deaths, and no recorded cases among Filipinos. Moreover, according to the available statistics, AFP more often affected the wealthier segments of the population than the poor. The existing "mainstream" hypotheses suggest that due to the growth of well-being and improved sanitary and hygienic regime, people began to get infected with poliovirus later, and, accordingly, get sick in complicated forms ("hygienic" theory). Within the framework of this article, I will not consider the noteworthy hypotheses about the relationship of AFP with smallpox vaccinations, diet, artificial feeding, etc., and so on. The fact, however, is that the risk of poliomyelitis in paralytic form increases from acute diseases suffered immediately before paralysis, and from the already mentioned immune deficiencies, temporary and permanent.

Be that as it may, acute flaccid paralysis posed a significant threat - the number of AFP cases at the peak of the epidemic, for example, in the United States alone was about 50,000 cases per year, while mortality in the first epidemics reached 5-10 percent - usually from pneumonia developing against the background of respiratory failure in the bulbar form of the disease (hereinafter - mortality as a percentage of AFP / paralytic forms of poliomyelitis). Gradually, doctors have achieved a decrease in mortality by changing the tactics of managing patients, including the use of the so-called. "Iron lungs" - lung ventilation devices due to the creation of negative pressure on the chest. For example, the death rate in New York from 1915 to 1955 decreased 10 times.

It is clear that polio paralysis was at the height of public attention in developed countries. The halls of hospitals, filled with "iron lungs" with children lying in them, have become part of the health care system and a typical plot of the mass media. The treatment remained symptomatic. The classic measure for combating epidemic diseases - quarantine - has been actively used since 1916, but did not give any effect. The non-paralytic forms of the disease were often unnoticed, and were so widespread that virtually the entire population would have to be isolated. The doctors had one more untapped tool for fighting infection - vaccination.

There have been tremendous efforts to develop a vaccine against poliovirus, especially in the United States. John Enders in 1949 developed a method for growing a virus in a test tube, in an artificial cell medium. This made it possible to create a virus in large numbers. Prior to this work, the only reliable source of viruses was the nervous tissue of the monkeys infected with it. On the other hand, it was believed that the virus can reproduce only in nerve cells, and it was extremely difficult to obtain and maintain cultures of these cells. Enders and his collaborators Weller and Robbins were able to find conditions under which poliovirus multiplied well in human and monkey embryonic cell culture. (In 1954 they received the Nobel Prize for this).

In 1953, Jonas Salk created his polio vaccine - he said that he had found a way to inactivate (“kill”) the virus using formaldehyde, heat and change the acidity, but retain the “immunogenicity” - the ability to cause a person to develop specific antibodies to poliovirus. These antibodies were supposed to, at a minimum, save a person from a severe course of the disease in case of infection. Vaccines of this type, with the inactivated virus, are called IPV (IPV, inactivated polio vaccines). Such vaccines theoretically cannot cause disease, and the person vaccinated with them is not contagious. The route of administration is injection into soft tissues.

[It should be noted here that the first chemically inactivated polio vaccine was tested in 1935. The percentage of deaths and maims among children with paralysis as a result of that experiment was so high that all work was stopped.]

Salk's work on his vaccine was funded by $ 1 million from the Roosevelt family's Polio Research Support Fund. It was believed that the President of the United States F. D. Roosevelt already suffered polio as an adult, after which he could only move in a wheelchair. Interestingly, today it is believed that Roosevelt was not sick with polio, because his symptoms were significantly different from the classic symptoms.

In 1954, the Salk vaccine was field tested. These trials were led by Thomas Francis (with whom Salk previously developed an influenza vaccine) and are probably the largest trials of any vaccine to date. They were funded by the private National Fund for Infant Paralysis (also known as the March of Dimes), cost $ 6 million (about 100 million at current prices), and a huge number of volunteers participated. The vaccine is believed to have demonstrated 83% effectiveness in trials in 2 million children.

In fact, Francis's report contained the following information: 420,000 children were vaccinated with three doses of a vaccine containing inactivated viruses of three types. The control groups consisted of 200,000 children who received placebo and 1,200,000 unvaccinated children. In relation to the bulbar form of paralysis, the efficiency ranged from 81% to 94% (depending on the type of virus), in relation to other forms of paralysis, the efficiency was 39-60%, in relation to non-paralytic forms, no difference was found with the control groups. Further, all vaccinated were in the second grade, and the control groups included children of different ages. Finally, those who contracted polio after the first vaccination were counted as unvaccinated!

Finally, in the same 1954, the first serious "victory" over poliomyelitis was won. It happened like this: until 1954, the diagnosis of "paralytic poliomyelitis" was made if a patient had symptoms of paralysis for 24 hours. He was synonymous with ORP. After 1954, for the diagnosis of "paralytic poliomyelitis" it became necessary that the patient had symptoms of paralysis in the period from 10 to 20 days from the onset of the disease. ANDpersisted during examination after 50-70 days from the onset of the disease. In addition, since the introduction of the Salk vaccine, laboratory testing for the presence of poliovirus in patients has begun, which, as a rule, did not happen before. In the course of laboratory studies, it became clear that a significant number of AFPs, previously registered as "paralytic poliomyelitis", should be diagnosed as diseases of the Coxsackie virus and aseptic meningitis. In fact, in 1954, a complete redefinition of the disease took place - instead of AFP, medicine began to fight a newly defined disease with prolonged paralysis and caused by a specific virus. From that moment on, the numbers of the incidence of paralytic poliomyelitis steadily went down, and comparison with the previous period became impossible.

On April 12, 1955, Thomas Francis addressed 500 selected doctors and experts in Michigan, and his speech was broadcast to 54,000 more doctors in the United States and Canada. Francis declared the Salk vaccine safe, powerful and effective. The audience was delighted. Here is an example from the Manchester Guardian newspaper, April 16 of the same year: “Perhaps only the overthrow of communism in the Soviet Union could bring as much joy to the hearts and homes of America as the historic announcement that the 166-year war against polio was practically approaching the end. Within two hours of Francis's announcement, an official license was issued and five pharmaceutical companies simultaneously began producing millions of doses. The US government announced that it wants to vaccinate 57 million people by mid-summer.

Thirteen days after the announcement of the safety and efficacy of the Salk vaccine, the first reports of cases among those vaccinated appeared in the newspapers. Most of them were vaccinated with the Cutter Laboratories vaccine. Her license was immediately revoked. As of 23 June, there were 168 confirmed cases of paralysis among those vaccinated, of which six were fatal. Moreover, it unexpectedly turned out that among those in contact with the vaccinated there were 149 more cases, and 6 more corpses. But the vaccine had to be "dead", which means - not contagious. The health service conducted an investigation and found that vaccine manufacturers were constantly detecting live virus in prepared vaccine batches: the number of lots with live virus reached 33%. And this despite the fact that the methods of measuring the activity of the virus were very limited. Obviously "inactivation" didn't work. Lots with a live virus were seized, but manufacturers did not check all batches in a row, but randomly. By May 14, the polio vaccination program in the United States was halted.

This story is called Cutter Incident. It resulted in a significant number of victims, and a sharp increase in the number of carriers of various types of poliomyelitis virus.

After the incident, the IPV production technology was changed - an additional degree of filtration was introduced. This new vaccine was considered safer, but less effective for the development of immunity. This vaccine has not been clinically tested at all. Although public confidence was significantly eroded, vaccination with the new Salk vaccine resumed and continued in the United States until 1962 - but in very limited quantities. According to official statistics, from 1955 to 1962. The incidence of paralytic poliomyelitis in the United States fell 30 times (from 28,000 to 900). Of these 900 cases of paralysis (in fact, this is only reported for half of the states), one in five children received 2, 3, 4, or even 5 IPV shots - and was still paralyzed (remember - under the new accounting rules).

It was in this situation that Dr. Seibin's oral polio vaccine (OPV) came into being. Back in 1939, Albert Bruce Seibin proved that poliovirus enters the human body not through the respiratory tract, but through the digestive tract. Seibin was convinced that the live vaccine, given by mouth, would contribute to the development of longer and more reliable immunity. But a live vaccine could only be made from viruses that do not cause paralysis. For this, viruses grown in kidney cells of rhesus monkeys were exposed to formalin and other substances. In 1957, the material for inoculation was prepared: weakened (attenuated) viruses of all three serotypes were obtained.

To test the pathogenicity of the material obtained, it was first injected into the brains of monkeys, and then Seibin and several volunteers tested the vaccine on themselves. In 1957, the first live vaccine was created by Koprowski and was used for some time for vaccination in Poland, Croatia and Congo. Parallel work on the creation of OPV based on the same Seibin viruses was carried out at that time in the USSR under the leadership of Chumakov and Smorodintsev - by this time the polio epidemic had begun in the USSR as well. Finally, in 1962, Seibin's OPV was licensed by the US Department of Health. As a result, live OPV based on Sibin viruses began to be used all over the world.

Seibin's OPV showed the following properties: 1) it was believed that after taking three doses, the effectiveness reaches almost 100%; 2) the vaccine was limitedly virulent (infectious) - i.e. the vaccinated were infected with the vaccine strains of the virus of the unvaccinated, who thus also acquired immunity. In sanitary-safe countries, 25% of those in contact were infected. Naturally, in Africa, these numbers should have been even higher. The huge advantage of OPV was and still is the low cost and ease of administration - the very same "a few drops in the mouth."

However, a unique feature of Seibin's OPV at that time, known since 1957, was the ability of its strains to turn back into a virus that damages the nervous system. There were several reasons for this:

1) vaccine viruses were weakened in terms of their ability to multiply in the nervous tissue, but they multiplied well on the intestinal walls.

2) The genome of poliovirus consists of single-stranded RNA, and, unlike viruses with double-stranded DNA, it mutates easily

3) At least one of the strains, namely the third serovariant, was only partially attenuated. In fact, he is very close to his wild ancestor - just two mutations and 10 nucleotide differences.

Due to the combination of these three conditions, one of the vaccine viruses (as a rule, the third serotype) from time to time, when multiplying in the human body (vaccinated or the one that got infected from it) turns into a disease-causing one and leads to paralysis. This usually happens with the first vaccination. According to American statistics, vaccine-associated paralysis, as it was called, occurred once in 700,000 vaccinated persons or their contacts after the first dose. It was extremely rare that this happened during subsequent vaccine injections - once per 21 million doses. Thus, for 560 thousand people vaccinated for the first time (remember about 25% of contacts), one poliomyelitis paralysis (paralysis according to the new definition) developed. In the annotations of the vaccine manufacturers, you will find a different figure - one case for 2-2.5 million doses.

Thus, OPV, by definition, could not defeat polyoparalysis while it was being used. Therefore, another replacement was used - it was decided to defeat the wild poliovirus. It was assumed that at a certain level of immunization of the Earth's population, the circulation of viruses will stop, and the wild virus, which lives only in humans, will simply disappear (as it theoretically happened with smallpox). Weak vaccine viruses are not a hindrance to this, since even a sick person, after recovering after a few months, completely eliminates the virus from the body. Therefore, one day, when no one on Earth has a wild virus, vaccination can be stopped.

The idea of eradicating "wild" poliomyelitis was taken up by the entire progressive community. Although in some countries (for example, in Scandinavia), not OPV, but improved IPV was used, in the "civilized" world, universal vaccination against poliomyelitis began. By 1979, wild poliovirus had disappeared from the Western Hemisphere. The number of polyoparalysis was fixed at a constant level.

However, the entire planet needed to eradicate wild poliovirus, otherwise, if the immunization program was terminated, any visitor from the Third World could reintroduce the virus. To make matters worse, for countries in Asia and Africa, poliomyelitis was far from being a priority health concern. A universal immunization program, even with cheap OPV (costing 7-8 cents per dose versus $ 10 for IPV), would have devastated their health program budget. The monitoring and analysis of all cases of suspected poliomyelitis also required significant funds. Through political pressure, public donations and government subsidies from the West, the World Health Organization was able to secure support. In 1988, the WHO World Assembly proclaimed a course to eradicate poliomyelitis by 2000.

As we approached the cherished date, the wild virus was encountered less and less. Another, final spurt was demanded by WHO officials - and countries held National Immunization Days, National Collection Months, and so on. Private and public organizations happily raised money to save small African children from disability - unaware that small African children had other, more important health problems in general and in particular. In total, over 20 years, the cost of the polio eradication program was conservatively estimated at about $ 5 billion (this includes both direct financial costs and an estimate of volunteer work). Of these, 25 percent was allocated by the private sector, especially the Rotary Club, which allocated a total of $ 500 million, and the Gates Foundation. However, even in the poorest countries, such as Somalia, at least 25-50% of total costs were borne by local communities and budgets.

But let's return for a while to … the macaques. As already mentioned, the viruses for both the Salk vaccine and the Seibin vaccine were obtained on cultures created from the cells of monkeys - rhesus monkeys. More precisely, their kidneys were used. In 1959, the American doctor Bernays Eddy, who worked at a state institute that was involved, in particular, licensing vaccines, on her own initiative tested cell cultures obtained from the kidneys of rhesus monkeys for oncogenicity. The experimental newborn hamsters that Eddie used developed tumors after 9 months. Eddie suggested that the cells of the monkeys may be infected with a certain virus. In July 1960, she presented her materials to her superiors. The bosses ridiculed her, banned her publication, and suspended her from polio vaccine testing. But in the same year, doctors Maurice Hilleman and Ben Sweet managed to isolate the virus. They named it simian virus 40, or SV40, because it was the 40th virus found by that time in the kidneys of rhesus monkeys.

Initially, it was assumed that only residents of the Soviet Union would become infected with SV-40, where at that time there was massive vaccination with Seibin's live vaccine. However, it turned out that the "dead" Salk vaccine is much more dangerous in relation to infection with SV-40: formaldehyde in a solution of 1: 4000, even if it neutralized the poliovirus, did not completely "inactivate" SV-40. And subcutaneous injection greatly increased the likelihood of infection. More recent estimates indicate that about a third of all Salk vaccine doses produced before 1961 were infected with live SV-40 virus.

The US government has launched a "quiet" investigation. There was no immediate threat to humans from the SV-40 virus at that time, and the government simply demanded that vaccine manufacturers switch from macaques to African green monkeys. Already released batches of vaccines were not recalled, the public was not informed of anything. As Hilleman later explained, the government feared information about the virus would cause panic and jeopardize the entire immunization program. At present (since the mid-90s) the question of the oncogenicity of the SV-40 virus for humans has been acute; the virus has been repeatedly detected in previously rare types of cancerous tumors. In laboratory research, SV-40 has been used all these years to cause cancer in animals. According to official estimates, the vaccine infected with the SV-40 virus has been received by Americans alone - 10-30 million, and about 100 million people worldwide. Currently, the SV-40 virus is found in the blood and semen of healthy people, including those born much later than the supposed end of the use of infected vaccines (1963). Apparently this monkey virus is now circulating among humans in some way. There is no information yet about what African green monkeys are sick with.

The history of SV-40 has demonstrated a new danger - contamination through polio vaccines with previously unknown pathogens. But what about the world immunization program? As the victorious year 2000 approached, two very unpleasant things began to be revealed. And here we come, in fact, to the reasons for the failure of the poliovirus eradication campaign.

First. It turned out that the body of some people vaccinated with live Seibin viruses does not stop excreting them into the environment after a couple of months, as expected, but releases it for years. This fact was discovered by chance in the study of one patient in Europe. The isolation of the virus has been recorded from 1995 to the present day. Thus, the practically insoluble problem arose of finding and isolating all long-term carriers of the virus after the termination of vaccination. But these were still flowers.

Second. Since the end of the 90s. Strange cases of polio paralysis and meningitis began to be reported from regions declared free of wild polio. These cases occurred in such different geographical regions as Haiti, Dominica, Egypt, Madagascar, different islands of the Philippines. Children who had previously been "immunized" with a live oral vaccine were also sick. The analysis showed that the paralysis was caused by several new strains of poliovirus ARISING from attenuated vaccine viruses. The new strains are apparently the result of mutation plus recombination with other enteroviruses, and they are as infectious and dangerous to the nervous system as the good old poliovirus. A new column has appeared in the WHO statistics: acute flaccid paralysis caused by viruses derived from vaccine …

By 2003, it became clear, as one doctor said, that the very notion of "virus eradication" needed to be eradicated. The chances of permanently eradicating all strains of the poliomyelitis virus are virtually negligible. It turned out that it is impossible to stop vaccination against poliomyelitis due to the elimination of the pathogen! Even if the cases of polio paralysis suddenly stop completely, it will be necessary to continue vaccinations to protect against circulating viruses. However, the use of a live oral vaccine becomes unacceptable. causes vaccine paralysis and epidemic outbreaks of mutant viruses.

Naturally, this had a very discouraging effect on the campaign's financial donors and health workers. Health officials are now proposing a switch to the entire vaccination program to IPV, a “dead” vaccine that currently costs 50 to 100 times the cost of OPV, and only if trained personnel are available. This is impossible without a radical price reduction; some African countries are likely to stop participating in the existing program - compared to AIDS and other health problems, polio control is not at all interesting.

What are the results of half a century of struggle?

Fatal acute flaccid paralysis (AFP) epidemics in developed countries stopped as gradually as they began. Was this decline the result of polio vaccination? The exact answer - although this seems the most likely, we do not know. Currently, according to WHO statistics, the incidence of AFP in the world is growing rapidly (three times in ten years), while the number of polio paralysis is falling - which, however, can be explained by the improvement in data collection. In Russia, 476 AFP cases were reported in 2003, of which 11 were polio (vaccine) cases. Half a century ago, they would all have been considered polio. In total in the world, according to official figures, from five hundred to a thousand children every year become paralyzed as a result of polio vaccination. Three types of wild poliovirus have been eliminated over significant geographic areas. Instead, polioviruses, derived from the vaccine, and about 72 viral strains of the same family, causing diseases similar to poliomyelitis, are circulating. It is possible that these new viruses were activated due to changes in the human intestine and general biocenosis caused by the use of vaccines. Many millions of people have been infected with the SV-40 virus. We have yet to learn about the consequences of introducing other components of polio vaccines, known and unknown, into the human body.

Evgeny Peskin, Moscow.

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