Prevention of HIV and hepatitis C

Viral hepatitis and HIV infection have become one of the main health problems in our country and in most countries of the world. Almost a third of the world's population is infected with the hepatitis B virus, and more than 150 million are carriers of the hepatitis C virus. In the Russian Federation, this figure ranges from 3 to 5 million people. Annually, from the pathology associated with viral hepatitis, including cirrhosis and hepatocellular carcinoma, 1.5-2 million people die. According to WHO forecasts, in the next 10-20 years chronic hepatitis C will become the main public health problem. As a result of its ubiquitous spread, the number of patients with liver cirrhosis can increase by 60%, with carcinoma of the liver by 68%, with decompensated liver damage by 28%, and liver disease deaths will double. In Moscow, according to 2006, infectious diseases, most often leading to death, are viral hepatitis, HIV infection, tuberculosis.

Even with the use of the entire arsenal of modern therapeutic agents, lethal outcome in acute hepatitis B is possible in 0.3-0.7% of cases; In 5-10% of patients chronic forms are formed, cirrhosis or primary liver cancer develops in 10-20% of them. For viral hepatitis C is characterized by asymptomatic flow, so the disease rarely falls into the field of vision of doctors, but patients pose a serious threat to other people, being the main source of infection. Hepatitis C is characterized by an unusually high incidence of chronic course of the process, leading to severe consequences. For one icteric case of acute viral hepatitis C, six cases of asymptomatic flow occur. The majority of patients develop chronic forms of the disease, in 40% of patients - leading to the development of cirrhosis, and then a third of them develop primary liver cancer. For a quiet, but insidious "temper" hepatitis C is called a "gentle killer."

The HIV pandemic also continues to grow. Currently, according to the estimates of the WHO and the United Nations AIDS Program (UNAIDS), 66 million people worldwide are infected with HIV, 24 million of them have already died of AIDS. In Russia, as of the end of 2006, the total number of recorded cases of HIV infection since registration of the first in 1987 is 391 610 people, of which about 8 thousand are no longer alive. The number of patients increases every year. For HIV infection is characterized by a long and almost imperceptible course for many years after infection, leading to a gradual depletion of the defenses of the body, and in 8-10 years - to the development of AIDS and life-threatening opportunistic lesions. Without antiretroviral treatment, an AIDS patient dies within a year.

[1], [2], [3], [4], [5]

Ways of transmission of HIV and hepatitis C

To the number of potentially dangerous biological fluids, which most often transmit viral infections, include blood, semen, vaginal secretions and saliva. Viruses can be contained in cerebrospinal, pericardial, synovial, pleural, peritoneal, amniotic, and also in other biological fluids contaminated with the blood of infected patients (urine, vomit, sputum, sweat and tear fluid). A rare source of viral infections can be blood products.

Transmission of the virus can occur when any of the listed fluids penetrate the blood through damaged skin or mucous membranes, as well as when splashes fall on the conjunctiva of the eye.

In recent years, the bulk of injecting drug users has been involved in the epidemic process of viral hepatitis. Infection occurs when syringes are shared, which maintains a high incidence rate. The sharp increase in the number of HIV carriers at the end of the last century is also associated with the use of psychotropic drugs intravenously. For the current stage of the HIV epidemic, the sexual mode of transmission of the virus is predominant. In recent years, the vast majority of people infected and deceased from AIDS in the world are not homosexuals and drug addicts, but people with heterosexual sexual behavior who do not use drugs.

Intrahospital infection with HIV and hepatitis C

Infection of patients with viral hepatitis in medical institutions becomes a serious problem, they account for 3-11% of the total number of infected. These viruses are most intensively transmitted in surgical departments with a long stay of patients, who underwent cavitary interventions and various invasive procedures, as well as manipulations with violation of the integrity of the skin; in offices where the disinfection and sterilization of instruments and equipment is complicated (hemodialysis, hematology, resuscitation and endoscopy).

In addition, patients can be infected by contact with the blood of an infected health professional. A big public response in 1990 was caused by the history of infection of one of its patients in Florida with an HIV-infected dentist during oral surgery. Later it was found that this doctor infected six more patients. The very first case of transmission of hepatitis B virus from a medical worker to a patient was registered in 1972, when a nurse infected eleven patients.

Data based on HIV and hepatitis B infection analysis suggest that the risk of infection increases with a high level of viremia, which is manifested either by a high "viral load" in the case of HIV, or by the presence of hepatitis B antigen (HBEAg).

Infection with HIV and hepatitis C by health professionals

In Western Europe, about 18,000 employees of medical institutions receive an annual hepatitis B virus (an average of 50 people a day). In Moscow in 2001, viral hepatitis was registered in 3% of health workers. The overall prevalence of HIV infection among medical personnel ranges from 0.4 to 0.7%.

A serious occupational hazard is the infection with the hepatitis B virus. Among medical personnel in the US, often in contact with the patient's blood, the incidence of infection is 15-33%, the rest of the population does not exceed 5%.

In Moscow in 1994, before the start of a broad program of hepatitis B vaccine prophylaxis, morbidity rates among health workers were 3-3.5 times higher than among adult residents of the city. An even more serious situation was observed in the Moscow region, where the average incidence of hepatitis B medics was 6.6 times higher than in the rest of the population. A similar situation was in many regions of our country. Only with the beginning of a wide implementation of hepatitis B vaccine prophylaxis among health workers, these indicators began to decline. However, if there is a violation of safety regulations or the emergence of emergency situations, there remains a high risk of occupational infection of unvaccinated staff of hospitals and polyclinics.

In recent years, the incidence of hepatitis C among health-care workers has increased significantly. According to various studies, in the US, the prevalence of hepatitis C among physicians is from 1.4 to 2%, which is comparable to the overall situation.

The high risk of infection of health workers with hepatitis and HIV viruses is associated with frequent and close contacts of physicians with blood. In the United States, 2,100 of the 8 million medical workers receive accidental injections or other cutaneous microtraumas at work every day, resulting in 2 to 4% of employees becoming infected with hepatitis. Almost daily, one health worker dies due to decompensated cirrhosis or primary liver cancer.

Damage to the skin most often occurs when using needles during or after medical manipulation. Especially high risk of skin damage when disassembling the system for intravenous infusion, when securing the needle in the vein, removing it, taking blood, putting the tip on the needle, and also during the change of bed linen.

The risk of infection with various viral infections in contact with infected blood is not the same. It is believed that the probability of infection with the hepatitis C virus is lower than hepatitis B. This is due to the fact that the infection with hepatitis C requires the ingestion of more infected blood. The risk of infection of health workers who receive accidental damage from needles for injection, hepatitis C virus is from 5 to 10%. There is one case of transmission of the hepatitis C virus with blood drops, caught on a conjunctiva. According to the Center for Disease Control and Prevention (CDC) of 1989, the frequency of transmission of hepatitis B virus to health workers after contact of damaged skin with HBEAg-positive blood of the patient is approximately 30%, and with similar contact with HIV-infected blood - 0.3% .

The highest rates of hepatitis B incidence were noted among resuscitators and surgeons. They are twice as likely to detect HBsAg and antibodies to the hepatitis C virus as compared to employees of other departments. The blood pressure, hemodialysis department, kidney transplantation and cardiovascular surgery are also among the most risky.

In Germany and Italy, among the various groups of physicians, a study has been conducted showing that the risk of infection of the operating staff increases with the increase in the length of service: the minimum number of infections falls on the first 5 years of work, and the maximum - for 7-12 years. In the group of the greatest risk - nurses (almost 50% of all cases), followed by doctors - 12,6%. Laboratory personnel, nurses and carers are exposed to significant risks. Now there are good reasons to treat hepatitis B and C as occupational diseases of physicians.

To date, there are also many confirmed cases of occupational HIV infection among health workers. In 1993, 64 cases were documented: 37 in the United States, 4 in the United Kingdom, 23 in Italy, France, Spain, Australia and Belgium. In 1996, the Center for Disease Control and Prevention (Atlanta, USA) published a report on 52 cases of proven HIV infection among health workers in the workplace, including 19 laboratory staff, 21 nurses, 6 doctors and 6 other specialists. In addition, 111 cases of possible occupational infection were reported. Almost all of them are associated with a needle prick when helping patients. In Russia, about 300 HIV-infected medical personnel have been identified, but they are infected either sexually or by injecting drugs with an unsterile syringe. There are only two documented cases of infection of medical personnel during work.

The highest risk of HIV infection is experienced by physicians assisting HIV-infected patients:

• average medical staff, mainly procedural nurses;
• Operated surgeons and operating sisters;
• Obstetricians-gynecologists;
• pathologists.

The risk of HIV infection depends on the degree of disruption of the integrity of the skin and mucous membranes. The risk of infection is greater, the more extensive and deeper the skin contact (nyxes and cuts). When tissue integrity is compromised, the risk of infection of the medical staff is about 0.3%; when HIV-infected blood gets to the mucous membranes, the risk is even lower - 0.09%, and when the intact skin contacts the blood, the risk is almost zero.

A needle prick after taking blood from a patient's vein is more dangerous than an injection after intramuscular injection. The risk also depends on the stage of the disease: in the acute stage of HIV infection, as well as in the late stages (AIDS), when the level of viremia is high, the danger is greatest. If the patient receives antiretroviral therapy, then its duration is important, as against the background of treatment there is a gradual decrease in the viral load (the content of the virus in the blood); The risk of infection from such a patient is reduced. In some cases for the conduct of post-exposure prophylaxis, it is important that the patient has resistant HIV strains.

Factors on which the risk of infection of medical personnel with HIV infection depends:

• degree of tissue integrity disorder;
• degree of contamination of the instrument;
• stage of HIV infection in the patient;
• receiving patients with antiretroviral therapy;
• the patient has resistant HIV strains.

Prevention of nosocomial and occupational infection with HIV and hepatitis C

Preventive measures should be aimed at preventing intra-hospital spread of infection and occupational infection of medical workers.

At the beginning of the HIV pandemic, it was understood that the condition of the patients and blood samples encountered during the work of the medical staff was allegedly unknown. This made it necessary to recommend the spread of the concept of "cautiously - blood and body fluids" in relation to all patients. The concept is known as universal precaution (CDC, 1987). Its use eliminates the need for mandatory urgent detection of patients with blood-borne infections and provides for treatment of each patient as a potential source of infection. Universal precautions include hand washing, the use of protective barriers in case of possible contact with blood, caution when using needles and other sharp instruments in all medical institutions. Instruments and other reusable equipment used in invasive procedures should be appropriately disinfected or sterilized. Subsequently, recommendations were developed to prevent transmission of HIV and viral hepatitis in professional contacts, including provisions for vaccination against hepatitis B, prevention of infection in dentistry and ambulance teams, use of postcontact chemoprophylaxis for suspected HIV infection, and prevention of HIV transmission from medical workers to patients during invasive procedures (CDC, 1990,1991,1993).

Ways to reduce the risk of infection of medical personnel

To reduce the risk of infection of medical personnel in health care facilities, it is recommended that:

• regular informing and training of medical workers in methods of prevention in contact with potentially infected material;
• prevention of work with patients of any profile, biomaterials and contaminated by them medical and technical workers who have skin lesions (wounds, cracks, wet dermatitis);
• provision of all workplaces with disinfectant solutions and a standard first-aid kit for emergency prevention;
• correct collection and treatment of the infected material, including various biological fluids, used tools and dirty laundry;
• use of personal protective equipment: gloves, glasses, masks, aprons and other protective clothing;
• carrying out of vaccination against hepatitis B of all medical workers, first of all belonging to the group of occupational risk;
• regular screening of all personnel for hepatitis and HIV viruses (before and in the process);
• strict administrative control over the implementation of the prevention program.

Actions to prevent infection of medical staff with viral hepatitis and HIV infection:

• attend classes on the prevention of parenteral infections and implement appropriate recommendations;
• Pre-plan their actions before any work with traumatic instruments, including their neutralization;
• Do not use dangerous medical instruments if they can be replaced by safe ones;
• Do not put caps on used needles;
• in a timely manner, throw used needles into a special, impenetrable, garbage collection container;
• without delay, report all cases of injuries when dealing with needles and other sharp objects and infected substrates in order to receive timely medical assistance and conduct chemoprophylaxis of infection;
• inform the administration of all the factors that increase the risk of injury in the workplace;
• Preference should be given to devices with protective devices;
• prepare medical workers at all levels: managers, doctors, nurses, social workers, consultants and other professionals;
• provide complete and accurate information on transmission and risk factors;
• to teach methods of combating discrimination and stigmatization;
• to maintain confidentiality.

Vaccination of medical workers against hepatitis B. For vaccination use one of the following two schemes:

• 0, 1, 6 months (the introduction of the second and third dose, respectively, 1 and 6 months after the first dose);
• 0, 1, 2 and 6 months (introduction of the second, third and fourth dose at 1, 2 and 6 months after the first dose, respectively).

The second scheme is recommended if, because of the high degree of risk, it is necessary to quickly provide protection from a possible infection. In such cases, emergency prophylaxis is based on the ability of vaccines to quickly launch a mechanism for developing specific immunity and thereby prevent the development of the disease, provided that the vaccine is administered early in the post-infection period. In case of an emergency, it is necessary to introduce intramuscularly specific immunoglobulin (HBsIg) containing antibodies to HBsAg (anti-HB5) in high concentration, at 0.12 ml (not less than 5 ME) per 1 kg of mass in the first day (but not later than 48 hours) body. At the same time, the first dose of the vaccine is administered. In the future, vaccination is continued according to the second scheme. The full course of vaccination is carried out if the absence of markers of viral hepatitis in the victim is found in the study of blood taken before the introduction of the vaccine. It is believed that it is advisable to start vaccinating physicians against hepatitis B before they start their independent work (at the first courses of medical schools and colleges). Vaccination protects the health worker and eliminates the possibility of transmission of infection to the patient.

At present, the scheme for accelerated immunization with vaccine is officially registered for the prophylaxis of viral hepatitis B. Scheme: 0-7-21 day, it is used in a number of hospitals in patients with upcoming planned surgical interventions and in other patients with planned invasive manipulations. The introduction of the vaccine in this scheme in 81% of the vaccinated leads to the formation of anti-HB3 in a protective concentration, but after 12 months an additional vaccine is needed.

The titer of anti-HB5, equal to 10 mIU / ml, is an indicator of the formation of protective immunity, which develops in more than 95% of vaccinated individuals and provides protection from infection not only with hepatitis B, but also with delta-hepatitis (the hepatitis D virus requires for its replication the presence hepatitis B virus, since it infects humans only in conjunction with the hepatitis B virus. This can increase the severity of liver damage).

If the antibody titer is less than 10 mIU / ml, a person remains unprotected from infection and a second vaccination is necessary. Some people even have a second vaccination ineffective. Medical workers with a lack of protective level of anti-HB5 should always follow the safety rules in the workplace.

To prevent infection with the hepatitis C virus, universal precautions should be followed and skin damage prevented, since there is no specific vaccine yet.

Postexposure prophylaxis of HIV infection

The main way to protect the health of health workers in an emergency situation with a risk of contracting HIV infection is through prevention measures, including prescribing antiretroviral drugs. In the event of an emergency, it is recommended:

• If the skin is damaged (cut, prick) and there is bleeding from the damaged surface, do not stop it for a few seconds. If there is no bleeding, then you need to squeeze out the blood, treat the skin with 70% alcohol solution, and then - 5% iodine solution.
• If the infected material enters the face and other exposed areas of the body:
  • Wash the skin thoroughly with soap and then rub it with 70% alcohol solution;
  • Eye wash with water or 0.01% solution of potassium permanganate;
  • If contaminated material enters the oral cavity, rinse mouth with 70% alcohol solution (do not drink!).
•  If contaminated or suspicious material enters your clothing:
  • this part of clothing immediately treated with one of the solutions of disinfectants;
  • disinfect gloves;
  • remove the robe and soak in one of the solutions;
  • clothes folded into sterilization boxes for autoclaving;
  • skin of hands and other areas of the body under contaminated clothing wipe with 70% alcohol solution;
  • shoes twice wipe with a rag soaked in a solution of one of the disinfectants.
• If the infected material hits the floor, walls, furniture, equipment and other surrounding objects:
  • pour the contaminated area with any disinfectant solution;
  • after 30 minutes, wipe.

Chemoprophylaxis of parenteral HIV transmission. In case of parenteral infection - damage to the skin by an instrument infected with HIV, ingestion of a material containing HIV, mucous membranes or damaged skin, chemoprophylaxis with antiretroviral drugs is recommended. The effectiveness of the following scheme of chemoprophylaxis is proved (the risk of infection is reduced by 79%): zidovudine - ingestion of 0.2 g 3 times a day for 4 weeks.

Currently, other schemes are also used, depending on the availability of antiretroviral drugs to health facilities. Efavirenz - 0.6 g per day + zidovudine - 0.3 g 2 times a day + 3TC lamivudine by 2 times a day. With the development of intolerance to one of the drugs, it is replaced in accordance with the general rules described in the guidelines for the antiretroviral therapy of patients with HIV infection. In addition, any regimens of highly active antiretroviral therapy may be used depending on the specific availability of antiretroviral medications for the health facility, with the exception of nevirapine-based regimens, as it increases the risk of side effects that threaten the lives of people with normal immunity. One-time administration of nevirapine with a subsequent transition to another scheme is acceptable in the absence of other drugs.

It is very important to start chemoprophylaxis as early as possible, preferably in the first two hours after a possible infection. If it can not be started immediately with a high-intensity therapy schedule, then as early as possible it is necessary to start taking the available antiretroviral drugs. After 72 hours after a possible infection, it is meaningless to start chemoprevention or to expand its scheme.

Recommendations for chemoprophylaxis can be obtained from a specialist of the AIDS Center by phone. At night, weekends and holidays, the doctor responsible for the hospital takes the decision to initiate antiretroviral therapy.

Registration of emergency situations is carried out in accordance with the laws and regulations adopted by the Federal Government and the subjects of the Federation. When registering an accident in a special journal, record the date and time of the incident, medical officer, his position; indicate the manipulation during which the accident occurred, and the measures taken to protect the health worker. Separately indicate the full name, age, address of the patient, when providing assistance, an accident occurred; details of HIV infection (HIV status, stage of the disease, antiretroviral therapy received, HIV RNA level, number of CD4 and SB8 lymphocytes) and the presence of viral hepatitis B and C. If the source patient or his HIV -Status are unknown, decide on the initiation of post-exposure prophylaxis based on the likely risk of infection.

On the fact of injury should immediately be reported to the head of the unit or his deputy, as well as to the AIDS Center and the State Sanitary and Epidemiological Surveillance Center (CGSEN). In each treatment-and-prophylactic institution, trauma received by health workers should be recorded and recorded as an accident at work.

Observation of injured employees

The medical worker should undergo an observation of at least 12 months after an emergency contact with the source of infection. Laboratory examination of the victim for antibodies to HIV is carried out in the event of an emergency, after 3, 6 and 12 months after. The victim should be warned that he needs to observe precautions throughout the observation period to avoid possible transmission of HIV to another person.

After the above-mentioned case in Florida, when a dentist infected his patients with HIV, appropriate documents were developed to prevent infection by pathogens transmitted from the blood by medical workers. Currently, such documents have legislative force in a number of countries, where committees have been formed for the management of physicians infected with hepatitis or HIV, and for their professional employment. In 1991, the US Centers for Disease Control and Prevention published recommendations on the prevention of HIV and hepatitis B transmission to patients during invasive procedures. Procedures with a high probability of transmission of a viral infection were listed. From the implementation of such procedures it is recommended to remove infected physicians (except for certain situations). However, in the United States to date, there are no restrictions in the professional activity of physicians infected with the hepatitis C virus.