Scientists have long known that human pox vaccines can be effective in preventing monkeypox.
A photo: GLOBAL LOOK PRESS
Monkeypox is getting closer and closer to the borders of Russia. On June 10, it became known about the first identified patient in Poland. In total, according to the latest data, by the end of the working week, 1356 cases of infection were confirmed in the world. In the top five are the UK – 321 cases, Spain – 259, Portugal – 209, Germany – 131 and Canada – 109 patients.
Russian Minister of Health Mikhail Murashko recently announced that a new vaccine against smallpox and drugs for its treatment are being tested in our country. Who needs to be vaccinated and when? What drugs are used to treat the infection? We asked the honored doctor of Russia, the leading scientific editor of the remote medical education service Vrachu.ru Mikhail Kagan about this.
TO WHOM AND IN WHAT DATE IS NEEDED TO BE VACCINED
– Initially, the contagiousness of the monkeypox virus is low. Perhaps now, for some reason, it has increased somewhat, – the expert notes. – However, standard anti-epidemic measures may be effective enough to bring the situation under control if the virus is brought to Russia.
Surveillance and the rapid identification of new cases are critical to contain the outbreak, explains Dr. Kagan. Those most at risk of infection are those who have had close contact with a person with monkeypox. (see below “Help” KP “).
– There is no need for mass vaccination today. It is enough to immunize several circles of contacts of the sick: primary contacts, then contacts of contacts, etc. Monkeypox has a long incubation period, averaging about 12 days. Therefore, you can have time to vaccinate an infected person, and this will stop the infection.
– What time frame do you need to meet?
– Even if the vaccination is carried out at the end of the incubation period, it is likely to make the course of the infection less severe. But the sooner an infected person gets the vaccine, the better. According to international recommendations, you need to have time to administer the vaccine within four days after infection in order to prevent the disease. If the vaccine is given later, it may reduce the symptoms, but the person is unlikely to avoid developing the disease.
In general, today it is believed that vaccination may be appropriate for people who “have been exposed to the monkeypox virus and have not received a vaccine in the past three years,” says Dr. Kagan.
TO THE POINT
How long will immunity last
“Scientists have long known that human smallpox (variola) vaccines can be effective in preventing monkeypox,” says the doctor. Both viruses belong to the same family. People vaccinated in childhood, when smallpox was a common childhood vaccination, may have some residual immunity. However, smallpox vaccination was discontinued in the USSR in 1980. Therefore, persons younger than 40-50 years of age may be more susceptible to monkeypox.
However, to date, there is no convincing evidence of how reliable protection is in previously vaccinated people, warns Dr. Kagan. How much has it really weakened over the past 50 years? Now nobody knows.
WHAT IS THE INFECTION TREATED?
“There is currently no specific treatment for infections caused by the monkeypox virus,” the expert explains. – At the same time, antiviral drugs developed for the treatment of patients with smallpox can be useful.
These drugs were developed after the eradication of smallpox throughout the planet. Since the risk that the pathogen is still stored in various laboratories (not only those that we know about according to official data – Ed.) and can be used as a biological weapon was not ruled out.
“Tecovirimat was registered in the US in July 2018,” says Dr. Kagan. – Studies of its effectiveness were conducted on animals. The result showed that the infected test subjects who received tecovirimat lived longer than those individuals who were injected with a placebo. In 2019, the drug was successfully used to treat a laboratory assistant who contracted the vaccinia virus due to a safety violation.
There is also the drug brincidofovir. It is a broad spectrum antiviral drug. The drug is active against many DNA viruses, including cytomegalovirus, adenovirus, varicella-zoster virus, herpes simplex virus, polyomaviruses, papillomaviruses, poxviruses, etc.
Immunoglobulin obtained from people vaccinated against smallpox may also be effective, the doctor notes (this is serum with antibodies from blood plasma. – Ed.).
In general, the evidence base for the effectiveness of existing drugs against monkeypox is still weak. In addition, there is little data on the availability of these drugs, the expert concludes.
BY THE WAY
The West African strain of monkeypox that is now spreading around the world tends to cause a mild infection in most people. However, for people with weakened immune systems and for pregnant women, this virus can be dangerous, Dr. Kagan warns.
HOW WE ARE
After contact with the patient – isolation for 21 days
Rospotrebnadzor issued recommendations to prevent the spread of monkeypox in the Russian Federation. The document prescribes to strengthen the surveillance of people arriving from epidemically disadvantaged countries (that is, those where the infection has been detected. – Ed.). A thorough epidemiological history should be taken from individuals who seek medical attention with symptoms not excluding monkeypox, primarily those arriving from abroad within 21 days, the recommendations say.
If someone in Russia is diagnosed with monkeypox, then all those who have been in contact with the patient are sent to isolation for a period of 21 days. It will be possible to serve quarantine either in a hospital or at home.
As for the vaccination of contact persons, in our country there are no official documents providing for it yet. It is impossible to get vaccinated just like that, at will. It will also not be possible to pass an analysis for monkeypox in the nearest laboratory. At the same time, both vaccines and test systems for diagnostics are at the disposal of the health authorities and epidemiological services, the authorities say.
Anyone who suspects monkeypox should see a doctor. Further, all necessary measures will be taken in accordance with the instructions of Rospotrebnadzor.
What is close contact with an infected person
The U.S. Centers for Infectious Disease Control and Prevention (CDC) rates the risk of contracting monkeypox as high if:
– a healthy person had unprotected contact (that is, without medical gloves. – Ed.) with the skin or body fluids of an infected person;
– the healthy person was within 1.8 meters (6 feet) of the sick person.