RU2216349C1 - Method for complex prophylaxis of anthrax - Google Patents

Abstract

FIELD: medicine, infectious diseases. SUBSTANCE: prophylaxis is carried out by the following schedule: for the first 6 h after infection antibiotic- -resistant mixed anthrax vaccine is administrated subcutaneously as a single human-dose and immunomodulating agent and antibiotic of broad spectrum effect are administrated for 5 days. Invention provides to create preventive protection for a long time against infection with high pathogen doses (100 LD₅₀) from the first day of combined using the complex of agents with specific and nonspecific prophylaxis of anthrax. Invention can be used for complex prophylaxis of anthrax. EFFECT: enhanced effectiveness of method. 4 tbl

Description

 The invention relates to medicine, namely to methods for the prevention and treatment of infectious diseases, and can be used for emergency integrated prevention of anthrax according to epidemiological indications in the epocenters.

 There is a traditional method for the emergency prevention of anthrax in the epidemic using the antibiotic doxycycline (in Russia) and ciprofloxacin (in the USA), or doxycycline (in Europe and the USA). The scheme of each of them provides for their oral use in a given course dose in case of infection threat (Instructions and guidelines for laboratory diagnosis, prevention and treatment of anthrax in humans. M., 1982; Guide for protection against chemical and biological weapons, Fort Detrick, 3rd edition, 1998).

 The disadvantage of existing schemes is the relatively low level of protection in the early (1 ... 5 days) periods of anthrax infection and the lack of protection in the long-term (6 or more weeks).

The first circumstance is due to the fact that preventive treatment provides only a level of protection of up to 70% of relatively small infectious doses: 10.. . 30 LD50 and does not provide protection against higher doses of the pathogen (over 50 LD ₅₀ ) in cases of massive infection with capsule cells (more virulent than spores) when cutting carcasses or eating meat from infected animals (Onishchenko G.G., Marinin L.I. et al. Microbiological diagnostics of anthrax. M., 1999), either by aerogenic infection by spores of workers at leather processing enterprises, or by a possible sabotage act of bioterrorists in crowded places (Siegrist DW The therent of biological attack: why concern now? // Emerg. Inf Dis. 1999. Vol 5 N 4 p. 505-508).

 The second circumstance is due to the fact that after the termination of the 5-day course of emergency antibiotic prophylaxis, the so-called non-germinating spores “dormant” in the lymphatic system germinate and cause the development of infection in the long term with weakening of the body, as evidenced by repeated cases of human disease 6 weeks after the initial infection and preventive antibiotic treatment (TV Inglesby, MD, DA Henderson, MD, JG Barlett et al. Anthrax us a Biological Weapon // American Medical Assotiation, Jama, May 12, 1999.- Vol. 281, No. 18, p. 143).

 There is a method of specific prophylaxis of anthrax, which consists in the formation of immunity by vaccinating people with live, or combined, or chemical anthrax vaccines, which allows, respectively, after double immunization after 30 days (live vaccine), or after a single vaccination in 7 days (combined vaccine) or after 3-fold immunization 2 months (chemical vaccine) prior to possible infection to form a tense immunity and allow personnel to enter the infection site (RF patent 2115433, 1998). However, these schemes of the known method of forming protection against anthrax also have two drawbacks. One of them is the “breakdown” of immunity in the first 14 days (for live) and in 1 ... 5 days (for combined and chemical) vaccines due to the weak formation of antibacterial and antitoxic immunity. The second drawback is associated with the high sensitivity of the spore component of vaccines to antibiotics, which, if combined with antibacterial drugs, adversely affects the formation of immunity at a later date. In addition, a chemical vaccine is characterized by the rapid extinction of antitoxic immunity.

The objective of the invention is the creation of guaranteed (100%) and long-lasting preventive protection against infection with high doses of the pathogen (100 LD ₅₀ ) from the first day of combined use of a complex of specific and non-specific prophylaxis of anthrax.

 The problem is solved due to the fact that emergency prophylaxis with an antibacterial drug additionally includes the combined use of an immunomodulator - lycopide or polyoxidonium and an antibiotic-resistant combined anthrax vaccine both at the time of infection and 6 hours after infection.

 Comparing the level of protection during subcutaneous and aerogenic infection with virulent cultures of the anthrax microbe with the dynamics of cellular and humoral indicators of specific resistance against the background of antibiotic prophylaxis, it is possible to extrapolate that the treatment-and-prophylactic complex: antibiotic + immunomodulator + antibiotic-resistant combination vaccine stops the development of anthrax for the first 6 days by increasing the therapeutic and prophylactic effectiveness of the antibiotic and accelerating the formation of vaccines second specific resistance, and in the next period of time (more than 6 weeks) due to the formation and preservation of long-term intense protivosibireyazvennogo antibacterial and antitoxic immunity.

The method of complex prevention of anthrax lesions is as follows. During the first 6 hours after infection, the contingent located in the epicenter is given once a subcutaneous dose of 1 human dose of an antibiotic-resistant combination vaccine containing (50 ± 10) • 10 ⁶ live spores of the vaccine strain STI-PR-4 and 35 ± 5 ID _{50 of} protective antigen (for FS 42-32-98-96). At the same time, doxycycline or pefloxacin is taken orally 2 times a day for 5 days and the use of lycopide or polyoxidonium at a daily dose of 1 for 5 days.

 The possibility of carrying out the claimed invention is shown by the following examples.

Example 1. The effect of emergency prevention on the intensity of post-vaccination immunity
The antibiotic-resistant combination vaccine was obtained according to the production schedule of dry combination, live and chemical vaccines of the NIIM MO RF 862-99 with the inclusion of the STI-PR-4 strain as its spore component (RF patent 2173342). To determine the post-vaccination immunity, animals (rabbits) were immunized once subcutaneously with a combined vaccine at a dose of 100 ± 20 million live spores and 35 ± 5 ID _{50 of} protective antigen and prototype vaccines: combined (STI-1 at a dose of 100 ± 20 million live spores and 35 ± 5 ID ₅₀ ), live (STI-1) at a dose of 100 million live spores and chemical (at a dose of 80 ID ₅₀ ). Antibiotic prophylaxis with pefloxacin mesylate was carried out 2 times a day for 5 days in a dose equivalent to a human dose.

Infection of animals was carried out with a virulent test strain 4-7 subcutaneously after 21 days at a dose of 100 LD ₅₀ according to the requirements of the FS for the combined vaccine (FS 42-3298-96). Immunity was determined by the percentage of surviving animals and the indicator of the preventive properties of blood serum (Burgas P.R. et al. // Journal of Microbiol., Epidemiol. And Immunol. 1972.- 6, p. 142-147). The results are shown in table 1. Analysis of the data presented in table 1 shows that against the background of the use of emergency prophylaxis, a live vaccine forms insufficiently strained immunity during all 3 months of observation: the level of protection was 0 ... 30%. The protective effect of a chemical vaccine in the long term (3 months) fades and decreases by 7-9 times. The high efficacy of the combined vaccine (75 ... 100% in terms of surviving animals) is maintained both in the early (on 7 ... 21 days) and in the long-term (90th day) terms, moreover, the antibiotic-resistant combination vaccine compared to the same a vaccine containing an antibiotic-sensitive spore component provides a higher level of protection. The increase in the degree of protection was: 30% in the indirect indicator of the preventive properties of serum (MSS) and 20% in terms of animal survival.

 Example 2. The synergistic effect of the combined use of lycopid (or polyoxidonium) and a combination vaccine against the phagocytic activity of neutrophils in rabbits.

 To identify synergies in the early (1 ... 5 days), the combined use of an immunostimulant - lycopide or polyoxidonium (SSC - Institute of Immunology of the Ministry of Health of the Russian Federation, Moscow) (in a dose equivalent to a dose for humans) and a combination vaccine (in a human dose) in blood samples taken from rabbits on days 1, 2, 3, 5, and 21, the content of active neutrophils and their absorption (with respect to latex) ability (phagocytosis index) were determined (Immunological methods / Edited by G. Frimel. - M., 1987). As follows from the data obtained, the values of the indicator of the phagocytic activity of neutrophils in 1.. .5 days were higher for the variant with the combined single use of the combined vaccine and lycopid. So, on day 3, the absolute content of active neutrophils increased from 68 to 76%, and the phagocytosis index on the second day of observation increased from 10 conv. units up to 19.2 srvc units respectively.

 Example 3. The synergistic effect of the combined action of lycopid or polyoxidonium and an antibiotic against anthrax infection in rabbits.

 In experiments on rabbits, the positive effect of the combined use of lycopide or polyoxidonium in a dose equivalent to a daily dose for a person with pefloxacin in a dose equivalent to a daily dose for a person was demonstrated during an emergency prevention course.

The research results are presented in table 2. As follows from the data in table 2, lycopid or polyoxidonium, used alone did not increase protection against anthrax, pefloxacin protected 60% of the animals treated after 3 hours, and 50% treated after 24 hours after infection a massive dose of anthrax pathogen (100 LD ₅₀ ). At the same time, with the prophylaxis and treatment of anthrax infection with the combined use of pefloxacin with lycopid or polyoxidonium, a 90% and 80% protective effect was obtained. Thus, the effectiveness of the antibiotic due to lycopid increased by 30%. The increase mechanism is associated with an increase in the activity of cells of the reticulo-endothelial system (RES), which localize the infection in primary complexes, which creates the conditions for effective treatment.

 Example 4. The effectiveness of the proposed method of preventive protection in comparison with the traditional method in the early stages (1 ... 5 days).

 Comparative data illustrating the level of protective effect when applying the proposed method and traditional in the early (1 ... 5 days) time after the start of emergency prevention, are presented in table 3.

As can be seen from the above results, emergency prevention (the traditional method of preventive protection) under specified conditions provides 1.. . 5 days protection level equal to 50 ... 70%. At the same time, the inventive method, comprising the combined use of an antibiotic-resistant combined vaccine, antibiotic and lycopid (polyoxidonium), allows to obtain at the same time a 100% level of protection when infected with a high dose of a pathogen (100 LD ₅₀ ).

 Example 5. The persistence of the protective effect of the proposed method of preventive protection compared to traditional in the long term after the end of the course of prevention.

The advantages in the effectiveness of the proposed method of preventive protection in comparison with the traditional one in the long term after the end of the emergency prevention course are demonstrated by the results shown in table 4. 2 weeks and 1.5 months after the completion of the antibiotic prophylaxis in the traditional way (including the antibiotic of prolonged action) re-infection of animals (rabbits and monkeys) with a dose of microbes equal to 100 LD ₅₀ , led to 100% death of animals. At this time, the residual concentrations of the antibacterial agent are practically ineffective and post-infectious immunity has not formed, and the research objects are at risk of re-illness. At the same time, in the group of infected animals, for the preventive treatment of which the claimed method was used, the survival rate of animals in these terms was 90 ... 100%. Therefore, the objects of this group are protected to a sufficiently high degree from reinfection by the causative agent of anthrax due to the formation of intense immunity induced by a specific component of the proposed complex of preventive protection.

Claims (1)

 A method for the comprehensive prevention of anthrax, including subcutaneous administration of an antibiotic-resistant combined anthrax vaccine in combination with an antibiotic and an immunomodulator, and prophylaxis is carried out according to the following scheme: the antibiotic-resistant combined anthrax vaccine is administered once subcutaneously in the first 6 hours after infection, within 5 days, an immunomodulator and a broad-spectrum antibiotic are administered.

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