Dogs, cats, hedgehogs, foxes and squirrels - how they kill people with rabies

Rabies is a vaccine-controlled zoonotic viral disease. At the stage of clinical symptoms, its mortality rate is 100%. Transmission of the rabies virus to humans in almost 99% of cases occurs from domestic dogs. At the same time, not only domestic animals, but also wild animals can suffer from rabies. The infection is transmitted to people and animals through bites or scratches, usually via saliva.

Rabies is present on every continent except Antarctica, with 95% of human deaths occurring in the Asian and African regions. Rabies is a neglected tropical disease (NTD) that predominantly affects poor and vulnerable populations living in remote rural areas. Approximately 80% of human cases occur in rural areas. Although vaccines and immunoglobulins can be used effectively to prevent rabies in humans, they are not always available or accessible to those in need. Worldwide, rabies deaths are rarely reported in official records; Victims of the disease are often children aged 5 to 14 years. With the average cost of a course of post-exposure prophylaxis (PEP) for rabies being US$40 in Africa and US$49 in Asia, such treatment often places a catastrophic financial burden on affected families, whose daily income averages US$1–2 per person [1].

Every year, more than 29 million people worldwide receive rabies vaccinations after animal bites. This is estimated to prevent hundreds of thousands of rabies deaths each year. The global economic burden of rabies transmitted by dogs is estimated at US$8.6 billion per year.

Prevention

Elimination of rabies in dogs

Rabies is a vaccine-preventable disease. The most cost-effective strategy for preventing rabies in humans is to vaccinate dogs. Vaccination of dogs reduces mortality from dog-borne rabies and reduces the need for AEDs in the care of patients injured by dog ​​bites.

Rabies Awareness and Dog Bite Prevention

An important step following the implementation of a rabies vaccination program is public education about dog behavior and bite prevention among children and adults, as this helps reduce both the incidence of rabies in humans and the financial burden associated with treatment for dog bites. To increase public awareness about methods of preventing and controlling rabies, it is necessary to carry out outreach work and disseminate information about the responsibilities of animal owners, ways to prevent dog bites and first aid after a bite. Forming an active position and sense of responsibility among citizens for the implementation of such programs allows for more widespread and effective dissemination of relevant information.

Immunization of people

To immunize people at the stages after exposure to the rabies virus (see PEP) and before it (used less frequently), the same vaccine is used. Pre-exposure immunization is recommended for persons at high risk in the workplace, in particular laboratory technicians handling live rabies virus and related viruses (lyssaviruses); as well as persons who, in the course of professional or private activities, may come into direct contact with bats, predators or other potentially infected mammals (veterinarians, game wardens).

Pre-exposure immunization may also be indicated for ecotourism enthusiasts and persons moving to remote areas with high risks of exposure to the rabies pathogen and limited availability of anti-rabies biological products. Finally, the possibility of immunizing children permanently or temporarily living in remote areas should be considered. When playing with animals, children are at increased risk of serious bites and sometimes do not report bites to adults.

Symptoms

The incubation period for rabies usually lasts 2–3 months, but can vary from 1 week to 1 year depending on factors such as the site of entry of the rabies virus and the viral load. Initial symptoms of rabies include fever and pain, as well as unusual or unexplained tingling, pinching, or burning sensations (paresthesia) at the wound site. As the virus penetrates the central nervous system, progressive, fatal inflammation of the brain and spinal cord develops.

There are two forms of the disease:

• Rabies manifests itself in the form of hyperactivity, agitated behavior, hydrophobia (fear of water) and sometimes aerophobia (fear of drafts or fresh air). Death occurs within a few days as a result of cardiac arrest.
• Paralytic rabies accounts for about 20% of all human cases. This form of rabies is less severe and usually lasts longer than the violent form. It is characterized by the gradual development of muscle paralysis starting from the site of the bite or scratch. Coma slowly develops and death eventually occurs. The paralytic form of rabies is often misdiagnosed, which contributes to underreporting of the disease.

Can a person infect an animal with rabies?

When people begin to become familiar with this disease by reading the relevant literature, they may wonder whether this terrible disease is transmitted from humans to animals. Theoretically, a person cannot infect an animal (as well as other people) with rabies, since the infection is transmitted only through saliva that enters the wound during a bite. One question logically follows from another: is it possible to transmit the rabies virus from person to person? There are no classical cases described in medicine, but there is information about a single transmission of the virus that occurred as a result of an ocular cornea transplant.

Diagnostics

Currently available diagnostic tools are not suitable for detecting rabies infection before the onset of clinical symptoms of the disease, and diagnosis may be difficult until specific signs of rabies such as hydrophobia or aerophobia appear. Intravital and postmortem confirmation of rabies in humans can be carried out using various diagnostic techniques aimed at identifying the whole virus, viral antigens or nucleic acids in infected tissues (brain, skin or saliva) [2].

What is rabies

Rabies is an infectious disease of viral etiology that gradually affects the entire peripheral nervous system. A person becomes infected through contact with the saliva of an infected animal through injuries to the skin or mucous membranes.

Currently, there is no treatment for the disease, but it is possible to prevent the development of rabies symptoms in a person after a cat bite through timely vaccination. If the vaccine was not administered before the first clinical signs appeared, then death is inevitable.

The rabies virus is a neurotropic microorganism whose size ranges from 100 to 150 nm. Bullet-shaped virions gradually penetrate the cerebral cortex through ascending neurons, then descend into the salivary glands and are released into the external environment.

In the cytoplasm of the affected brain cells, during the life of the pathogen, specific inclusions are formed - Babes-Negri bodies. Their detection plays a leading role in the post-mortem diagnosis of the disease in cats and other animals.

Transmission of infection

Infection in humans usually occurs as a result of a deep bite or scratch inflicted by an infected animal, with up to 99% of transmission to humans occurring from rabid dogs.

In the Americas, most human deaths from rabies are now caused by transmission from bats, since transmission from dogs has largely been interrupted in the region. In addition, bat rabies poses an increasing threat to human health in Australia and Western Europe. Cases of human deaths resulting from contact with foxes, raccoons, skunks, jackals, mongooses and other species of wild predatory animals that carry rabies are very rare, and there is no information confirming the transmission of rabies through rodent bites.

Transmission of infection can also occur if the saliva of an infected animal comes into direct contact with mucous membranes or fresh wounds on human skin. Extremely rare cases of rabies infection through inhalation of aerosols containing the virus or through transplantation of infected organs have also been described. Transmission from person to person through a bite or through saliva is theoretically possible, but has never been confirmed. The same applies to people becoming infected by consuming raw meat or milk from infected animals.

Who is at risk?

• People who have been bitten by wild or domestic animals;
• People living in rural areas and keeping animals at home that have not been vaccinated against rabies;
• People who travel to developing countries (Southeast Asia, Africa);
• People who go outdoors and come into contact with wild animals (raccoons, foxes, bats, etc.);
• Trappers and hunters;
• Veterinarians;
• People who work in nurseries, zoos, animal shelters;
• People who work with the rabies virus in the laboratory.

Post-exposure prophylaxis (PEP)

Post-exposure prophylaxis (PEP) involves providing first aid to a bite victim after exposure to the rabies virus. It helps prevent the virus from entering the central nervous system, which inevitably leads to death. The PEP is as follows:

• copious rinsing and local treatment of the bite or scratch wound as soon as possible after possible contact;
• a course of immunization with a powerful and effective rabies vaccine that meets WHO standards; And
• if indicated, administration of rabies immunoglobulin (RAI).

Prompt medical care after exposure to the rabies virus is an effective way to prevent symptoms and death.

Copious rinsing of the wound

This type of first aid involves immediately and thoroughly irrigating and washing the wound with soap and water, detergent, povidone-iodine, or other substances that remove and kill the rabies virus for at least 15 minutes.

Risk of exposure and indications for AEDs

Depending on the degree of contact with an animal that may presumably be infected with rabies, a full set of PEP may be recommended according to the following scheme:

A PEP is required for all Category II and III exposures assessed as presenting a risk of developing rabies. The risk increases in the following cases:

• it is known that the mammal that bit a person belongs to a species that is a carrier or vector of rabies;
• the exposure occurred in a geographic area in which rabies is still present;
• the animal appears sick or exhibits abnormal behavior;
• the wound or mucous membrane is contaminated with animal saliva;
• the bite was not provoked;
• the animal is not vaccinated.

If the animal's vaccination status is not definitively established, it cannot be considered as a determining factor in deciding whether to initiate ECP. Such situations are possible when the organization or control of the implementation of dog vaccination programs is unsatisfactory due to lack of resources or low priority of such programs.

WHO continues to actively advocate for the prevention of rabies in humans through the elimination of rabies in dogs, the implementation of strategies to prevent dog bites, and the widespread introduction of intradermal AEDs, which reduce the volume and thus reduce the cost of cultured cell culture by 60-80%. vaccines.

Comprehensive management of bite cases

If possible, the bite should be notified to veterinary authorities, and the biting animal should be identified, isolated, and either quarantined for observation (in the case of healthy dogs and cats) or referred for immediate laboratory evaluation (in the case of dead or euthanized animals with clinical signs). signs of rabies). AED must be continued for a 10-day observation period or until laboratory results are available. Preventive treatment may be interrupted once it is confirmed that the animal is not infected with rabies. The full course of PEP must be completed if an animal with suspected rabies cannot be caught and tested. Veterinary and medical authorities are encouraged to jointly conduct contact tracing to identify other suspected rabid animals and human bite victims so that appropriate preventive measures can be taken.

Rabies in humans

Rabies is an infectious disease that develops as a result of infection with the Rabies virus. The disease is characterized by a rapid and severe course, as well as a high probability of death. The virus enters the human body after being bitten by an infected animal.

MedEx Clinic recommends getting a rabies vaccination if you have pets living with you. This is the most effective measure to prevent a dangerous disease.

Routes of infection

The causative agent of rabies is found in the saliva of infected animals and is sometimes found in tear fluid and urine. It is distributed mainly among homeless and wild animals that gather in flocks. Treatment of the disease is complicated by the fact that people often do not pay attention to contact with an aggressive animal and consult a doctor too late.

Animals that carry rabies are:

• dogs;
• cats;
• foxes;
• the bats;
• hedgehogs;
• rats.

Less commonly, rabies infection occurs as a result of bites from badgers, raccoons, wolves, birds and fleas. Not only wild animals, but also domestic animals can carry the pathogen: they become infected while walking in open areas, parks, plantations and forests. Once infected, they can transmit the virus to humans.

It is difficult to recognize a wild animal infected with rabies; aggressive behavior may be typical for it. With pets the situation is simpler. Once infected, they become secretive, hiding and avoiding people. As rabies progresses, outward signs of aggression appear - towards a person or objects in the home. The animal later falls into a coma and dies.

Symptoms of rabies in animals vary depending on the form of the disease:

• Quiet. The animal does not behave aggressively. There is increased salivation, which interferes with eating. The disease ends in coma and death.
• Violent. The animal behaves aggressively. Later, convulsions begin and it dies.
• Atypical. Characterized by vague symptoms. Severe diarrhea may occur. Despite the apparently mild course of the disease, the animal dies.

The incubation period for rabies in animals is 10 days. This means that a pet can be infected without showing any outward signs. Therefore, you should not focus on his behavior.

The following routes of rabies infection are distinguished:

• when bitten by an infected animal or when its saliva gets on a damaged area of ​​skin or mucous membrane;
• when inhaling air containing particles of saliva from an infected person;
• upon contact of unprotected skin with the corpses of animals that died of rabies, their biological materials;
• from mother to child during pregnancy.

There are no officially documented cases of human-to-human transmission of rabies.

Symptoms

In humans, rabies is characterized by a long incubation period. It can be 1-3 months or more. During this period, the person will be infected, but the outwardly dangerous disease will not manifest itself in any way. Symptoms of rabies usually become noticeable after a few weeks if the bite is localized to the face, arms or torso.

External signs of the disease depend on how long has passed since the moment of infection. In this regard, in medicine there are 3 stages, or periods of rabies.

First stage

The first sign of rabies is discomfort at the site of the bite, and the wound may already have healed by this point. They are expressed in discomfort, burning, and sometimes suppuration and hyperemia. The bite site becomes swollen.

At the first stage of rabies, other symptoms may be observed:

• increased body temperature;
• apathy or overexcitement;
• inexplicable fear;
• loss of appetite;
• weight loss.

If the bite site is located on the face, auditory and sound hallucinations occur. The person ceases to control himself, and the disease gradually progresses, moving into the second stage of rabies.

Second stage

In the second stage, the symptoms of rabies from the bite worsen. The patient develops hydrophobia - acute fear of water. He is so afraid of water that he cannot even drink it: an attempt to quench his thirst causes panic attacks, accompanied by breathing problems and spasms of the larynx muscles. Even the sound of running water can trigger a panic attack. The inability to quench thirst leads to dehydration.

The second stage of rabies is characterized by increased sensitivity to any external irritants. A person begins to be afraid of loud sounds, bright lights, and blowing wind. The reaction to an irritant can be very different - violence, manifestation of physical aggression.

Other symptoms characteristic of the second stage of a viral disease:

• dilated pupils;
• gaze directed at one point;
• increased sweating;
• heavy and intermittent breathing;
• confusion;
• hallucinations.

At the second stage, during an attack, cardiac arrest may occur. This is the most common cause of death from rabies. Otherwise, the patient's consciousness temporarily clears up.

Third stage

The third stage of rabies is the stage of paralysis. For a short time, the patient’s condition improves: convulsions disappear, breathing becomes smooth, and behavior becomes calm. But this is a deceptive improvement.

After some time, the temperature of a patient infected with rabies rises to 40 degrees. He develops tachycardia, and then paralysis of all organs and systems. Death occurs as a result of paralysis of the heart or respiratory system.

Diagnostics

After contact with a presumably infected animal has taken place, the wound must be treated. To do this, it should be washed with soapy water, despite severe pain, and the edges should be disinfected with alcohol. Then you need to cause profuse bleeding from the wound: there is a possibility that this measure will help remove particles of the virus that have entered the blood. To do this, you need to try to carefully cut the wound and squeeze the blood out of it.

After taking the measures, you must go to the nearest hospital as soon as possible: self-medication for rabies is prohibited. If you cannot treat the wound yourself, call an ambulance.

The doctor needs to provide as detailed information as possible about the incident:

• write a description of the infected animal;
• talk about the circumstances of the infection;
• describe your symptoms.

This information will help the doctor assess the risks in advance. If the bite was caused by a pet, it will be taken away for observation for a 10-day period. Sometimes salivary gland cells are collected and laboratory mice are infected with them: this allows one to accurately confirm or refute the presence of rabies. If rodents begin to develop paralysis, the diagnosis is confirmed.

After studying the medical history, the doctor prescribes laboratory tests. They allow you to determine the presence of antibodies in the blood, as well as antigens in skin biopsies and the cornea. External manifestations of rabies may be confused with symptoms of encephalitis, tetanus, delirium tremens, so the patient may be prescribed additional tests. Sometimes the diagnosis is made only posthumously, by analyzing the brain of the deceased.

Treatment

For a long time, treatment for rabies meant alleviating the condition of the infected patient: therapy was aimed at reducing suffering before death. It was possible to save him only in one case - if a person sought help before the first signs of the disease appeared. The situation has changed since 2005: now it is possible to provide assistance to someone infected with the rabies virus, despite a serious deterioration in health.

However, the effectiveness of treatment largely depends on how quickly a person sees a doctor. The prognosis is becoming more unfavorable every day. In the later stages of rabies, treatment is virtually ineffective, so it is important to see a doctor as soon as possible.

Therapy is based on mandatory vaccination. A patient infected with the rabies virus is injected into the bloodstream with a special drug - immediately after visiting a doctor, and again on the 3rd, 7th, 14th and 28th day. The World Health Organization also recommends vaccination 3 months after the bite to minimize the chance of developing the disease.

The vaccine injection site is chosen depending on the age group:

• for adults - into the deltoid muscle;
• for children - through the hip.

The rabies vaccine is needed not only after a bite from an animal infected with rabies, but also in other cases - when injured by an object that may have particles of infected saliva on it. Contact with a sick animal without breaking the skin is not dangerous and does not require vaccination.

Treatment of rabies gives results if vaccination is carried out no later than 2 weeks from the moment of infection. It is performed on an outpatient basis: there is no need to go to the hospital. The exception is women during pregnancy. They must be regularly monitored by a doctor.

Treatment of rabies also includes symptomatic therapy. The patient is administered drugs that suppress the development of convulsive syndrome - chlorpromazine, diphenhydramine, morphine. In case of serious condition, he is placed in a room, protected from sharp sounds, bright light and any other factors that can provoke an attack.

Until the end of rabies treatment, the patient is prohibited from drinking alcohol, visiting the bathhouse or sauna, or undergoing excessive physical exertion. It is important to get proper rest, get enough sleep, and avoid overwork or chronic stress.

As an additional measure, no later than 24 hours after infection with rabies, the patient may be prescribed immunoglobulin injections.

If the condition of a person infected with rabies is severe, he is put into a coma. Initially, this treatment, called the Milwaukee Protocol, was considered experimental. But it has demonstrated positive results and is now used in medical practice. The patient is put into a coma using special drugs, and then given injections of antiviral drugs. After the rabies viral infection is destroyed, the person is brought back to consciousness. The method is not always applicable due to the high risk of death.

Prevention

Preventing rabies is the most reliable way to reduce the risk of future infection. The human body is very difficult to tolerate this disease, and given the long incubation period, the likelihood of recovery is extremely low. The main preventive measure is to vaccinate all stray animals against rabies, but it is difficult for an ordinary person to influence its implementation.

Personal preventive measures:

• minimize contact with stray and wild animals, especially those showing aggression;
• do not buy animals “from hand”, without having the appropriate documents;
• stray animals picked up from the street should be immediately shown to a veterinarian;
• vaccinate pets;
• monitor the behavior of your pet, especially after contact with other animals;
• After a bite, consult a doctor for help.

Rabies prevention measures are mandatory for all age groups of the population, but it is especially important to explain them to children and adolescents. They often show interest in stray animals, and therefore are at risk.

Get a rabies vaccination in Moscow

Rabies is a dangerous infectious disease that can be fatal. Therefore, if you notice its symptoms, we recommend that you do not delay, but immediately seek medical help. The MedEx Personal Medicine Clinic is open on weekdays and also provides patients with video consultations remotely.

We represent a multidisciplinary medical center staffed by world-class experts. To consider complex cases, a council of doctors from one or more specializations gathers.

WHO activities

Rabies is included in the new WHO roadmap for 2021–2030. The fight against rabies, given the zoonotic nature of this disease, must be carried out within the framework of close interagency cooperation at the national, regional and global levels.

• As part of a comprehensive approach to health, WHO, FAO (Food and Agriculture Organization) and OIE (World Organization for Animal Health) have made rabies control a priority.
• The WHO-led Unite to Stop Rabies initiative serves as a multi-stakeholder platform to mobilize and share rabies resources and coordinate global efforts to eliminate rabies in humans, with the goal of achieving zero dog-borne human deaths by 2030 rabies.
• WHO works with a range of partners to provide guidance and support to countries in developing and implementing national rabies elimination plans.
• WHO regularly reviews and disseminates technical guidance on rabies control issues [3], such as epidemiology, surveillance, diagnostics, vaccines, safe and cost-effective immunization [4], strategies for the control and prevention of rabies in humans and animals, and practical implementation of programs [5 ] and palliative care for people with rabies.
• During rabies elimination, countries can ask the WHO to certify that they have achieved zero mortality from dog-borne rabies [3], submit an application for approval of a canine rabies control program to the OIE, or independently declare the elimination of canine rabies [6].
• In 2021, Mexico became the first country to be certified by WHO as having eliminated deaths from rabies transmitted by dogs.
• WHO's priorities to help strengthen the global movement towards universal health coverage include including rabies biologics on national schedules and promoting increased access to AEDs for poor and rural populations.
• In 2021, the GAVI Alliance included human rabies vaccines in its Vaccine Investment Strategy 2021–2025, which will support increased uptake of EPPs for suspected rabies cases in GAVI eligible countries; WHO will continue to provide advice to the Alliance on strategies and methods for introducing rabies vaccine in countries that request it.
• To evaluate the effectiveness of rabies control programs and to increase public awareness and outreach efforts, monitoring and surveillance of such programs is necessary.

The main document that will guide efforts to combat NTDs in the next decade is the Roadmap to combat NTDs for the period until 2030, which indicates phased regional targets for the elimination of rabies [7].

The following principles are key to sustaining rabies control programs and expanding them to surrounding areas: start small, implement local rabies programs through comprehensive incentives, demonstrate program success and cost-effectiveness, and engage government agencies and affected populations.

Elimination of rabies requires sufficient long-term investment. Effective and proven methods of attracting attention and mobilizing political will in this area are demonstrating success on the ground and publicizing the rabies problem widely.

[1] Zero by 30: the global strategic plan to end human deaths from dog-mediated rabies by 2030 [2] WHO, Laboratory techniques in rabies. Fifth edition. Volume 1 and Volume 2 [3] WHO expert consultation on rabies: Third Report. TRS N°1012 [4] Rabies vaccines: WHO position paper – April 2021 [5] Scientific and operational updates on rabies [6] OIE Rabies Portal [7] Ending the neglect to achieve the sustainable development goals: a road map for neglected tropical diseases 2021–2030

Anti-vaxxers are not just among people

The problem of rabies is global. Just in August of this year, rabies quarantine was declared in neighborhoods of hundreds of cities around the world: in Kharkov, Delhi, London, Marseille, Rio de Janeiro...

In Russia this year, local quarantine was announced in Buryatia, Khakassia, the Belgorod region and the Moscow region. Thus, during an epidemiological investigation conducted by Rospotrebnadzor, it was established that on May 15, 2021, in the village of Tomilino, Lyubertsy district, Moscow region, a stray kitten was picked up and brought to Moscow, to the South-Eastern Administrative District. Six days later, the animal died, the corpse was taken to the Lyubertsy veterinary station in the Moscow region. The laboratory test results were positive for rabies. The kitten's owner received a course of anti-rabies treatment at her place of residence, and her house was treated by the extermination station staff.

pixabay.com/

Due to the quarantine, exhibitions of dogs and cats, their export outside the district, as well as the trade in pets and the capture of wild animals were prohibited for almost two months. As the head of the Moscow Veterinary Committee Alexei Sautkin , since the beginning of 2021, six cases of rabies in animals have been identified in Moscow (two in cats and six in wild animals). Experts say that even one case of rabies is a reason for special caution.

The rabies virus is a particularly dangerous and deadly infectious disease; no one is immune from it: the virus affects almost all warm-blooded animals, including humans. According to the World Health Organization (WHO), about 60 thousand people die from rabies every year around the world (about 34 thousand people in Asia), and four out of every ten are children under 15 years of age.

Rospotrebnadzor notes that in recent years, in most of the Russian Federation, there has been a deterioration in the epizootic situation regarding rabies: the population of stray dogs and cats in populated areas is increasing. The forest is also restless: in 80% of cases the main wild carrier of rabies is the fox, raccoon dog - 14%; wolf - 1%. Rodents, mustelids and other canids make up 4-5%.

Rabies has already been registered in farm animals in eleven regions of Russia: in the Moscow, Tver, Ryazan, Kursk, Bryansk, Chelyabinsk, Sverdlovsk, Voronezh, Lipetsk regions, in the Krasnoyarsk Territory and the Republic of Buryatia.

Nevskie News / Stepan Yatsko

Every year, about 400-500 thousand people become victims of animal attacks, about half of them need anti-rabies treatment (antiviral vaccination) and more than 40 thousand people must receive additional anti-rabies immunoglobulin. Moreover, in most regions of the country, rabies vaccinations for animals and people are free - just come.

However, even here there are anti-vaccination communities who deny the benefits of vaccination and are even proud of the fact that they do not vaccinate their animals or themselves (including against deadly rabies). But it’s enough for an unvaccinated domestic cat to go to the country in the summer and chat there, for example, with a sick mouse or hedgehog, and purring death comes to your doorstep.