Since appendicitis and smallpox are both part of the orthopedic virus family, experts say some vaccines will work against both. But the vaccines recommended for use against smallpox today are different from those used in last century’s global effort to eradicate smallpox, according to the World Health Organization (WHO). “Some countries have retained strategic supplies of older smallpox vaccines from the Smallpox Elimination Program (SEP) completed in 1980,” she said. Temporary WHO guidance on monkeypox vaccination issued on Tuesday. “These first-generation vaccines stored in national stockpiles are not recommended for smallpox at the moment, as they do not meet current safety and manufacturing standards.” Monkey pox causes flu-like symptoms and skin lesions and is spread through close contact. Both the WHO and Canada National Advisory Committee on Immunization (NACI) has now released guidelines on the vaccine to be used against monkeypox and who can benefit from it.
What monkeypox vaccine is available in Canada?
The vaccine approved for monkey pox immunization in Canada is MVA-BN or Modified Vaccinia Ankara – Bavarian Nordic. Bavarian Nordic, based in Denmark, is the company that makes it. In Canada, the vaccine is branded Imvamune. (Named Imvanex in the European Union and Jynneos in the US) Imvamune was originally approved in Canada for “emergency use” against smallpox in November 2013 as part of the federal government’s emergency plan to immunize people if the deadly disease ever reappears. In 2020, Canada extended the vaccine license to include monkey pox immunization, according to NACI documents. An employee of the Bavarian Nordic vaccine company works in one of its laboratories near Munich, Germany, on May 24. The company’s Imvamune vaccine has been approved in Canada for monkeypox immunization. (Lucas Barth / Reuters) Conventional smallpox vaccines stopped in Canada in the early 1970s. But because the viruses are related, these smallpox vaccines may have provided some degree of immunity to smallpox, experts say. “It is possible that this, you know, mass vaccination campaign for smallpox really kept monkey pox under control for many years,” he said. Isaac Bogoch, infectious disease specialist at Toronto General Hospital. But most people under the age of 50 in Canada did not receive that protection – and that may be one of the reasons we now see monkey pox, he said.
How is Imvammune different from the old smallpox vaccine?
Imvammune contains an attenuated strain of the vaccinia virus, which triggers the immune response to fight smallpox and smallpox. Unlike the original smallpox vaccine, this attenuated virus does not reproduce, which means that it cannot make copies of itself. Early-generation vaccines based on reproducible vaccinia strains have led to unpleasant side effects for some and could be problematic for people who are immunosuppressed, said Dr Zane Chagla, an infectious disease specialist at McMaster University in the University of McMasteron. In addition, older generations of the smallpox vaccine are given differently. Instead of a regular syringe, the healthcare provider uses a “double needle” with two teeth and pierces the skin repeatedly to get the dose.
Who should consider monkey pox vaccination?
Infectious disease experts say that monkey pox does not currently affect the majority of the general Canadian population, although anyone can catch the virus if they are in close physical contact with someone who is infected. The LGBTQ community, especially men who have sex with men, are at a disproportionate risk of infection in this outbreak, they say. Healthcare workers or laboratory workers working directly with orthopoxia viruses could also be at risk. As a result, experts say smallpox vaccines should be offered to those endangered populations as a precaution. The vaccine can also be given to those who have already been exposed to someone with monkeypox – known as post-exposure prophylaxis. In both cases, the monkeypox vaccination approach must be targeted, they say. “This is not a widespread vaccine for everyone; it is a risk-based vaccine,” Chagla said. Bogoch agreed. “I do not think we are close to launching, you know, vaccine campaigns for the general public,” he said. “Right now, this is going to be a very focused and targeted vaccination campaign for people who have been exposed and for people who are at the highest risk of catching this infection.”
How many doses?
Both WHO and NACI recommend two doses of Imvamune, 28 days apart. One possible exception, according to NACI guidelines, is someone who has been vaccinated against smallpox in the past. In this case, they could only be given one dose to serve as souvenirs.
Are there any possible allergens in the vaccine?
Yes. NACI says Imvamune contains the following ingredients:
Traces of residual DNA and host cell protein. Tromethamine (Trometamol, Tris). Benzonase. Gentamicin and ciprofloxacin.
