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As the world races to learn more about the rapidly emerging outbreaks of monkeypox, the speed with which cases are detected signals a major change in the virus’s behavior and ability to spread from person to person unnoticed.
Two cases of monkeypox confirmed in Quebec and Canada’s chief public health official says provinces continue to investigate on Friday “several dozen” possible cases across Canada – more likely to be confirmed in the coming days and weeks.
World Health Organization (WHO) said on Friday that there are currently about 80 confirmed cases worldwide, with another 50 awaiting investigation and more likely to be reported with the expansion of global surveillance.
West and Central Africa Thousands of endemic cases are usually reported each year, but cases of monkeypox outside Africa are rare and largely travel-related. What distinguishes this global epidemic is the increase in cases without known origins of travel.
“The global spread is worrying. It’s not something we’re used to, especially with monkeypox,” said Jason Kindrachuk, an assistant professor of viral pathogenesis at the University of Manitoba and the Department of Emerging Virus Research in Canada who studied monkeypox.
“What we are seeing now is unprecedented. We have many geographical locations around the world that report cases … What is the epidemiological link between these cases and is there anything related to changes in the virus? ”
WATCH Officials are investigating 2 confirmed cases in Montreal:
Montreal officials are investigating suspected cases of monkeypox
In Montreal, health officials are investigating several suspected cases of monkeypox, a rare viral disease with symptoms including fever, headache and skin lesions. Experts point to the smallpox vaccine – which has not been routinely available in Canada for decades – as a potential protection against the disease.
Does monkeypox mutate?
There are two main strains or “logs” of monkeypox: the Congo strain – which is heavier, with up to 10 percent mortality – and the West African strain, which has a mortality rate of about one percent.
Transmission may be the result of close contact with respiratory secretions or skin lesions of an infected person or of recently contaminated objects. Symptoms may include fever, severe headache, swollen lymph nodes, back pain, muscle aches, lack of energy, severe rash and lesions.
The current strain circulating worldwide seems to be West Africanbut genomic sequencing is currently underway in Canada and around the world to determine if there are any different genetic mutations.
“The question is always, has things changed?” Kindrachuk said.
“What you’re sure to hear over the next few weeks is a lot of information coming from people who have specifically looked at samples from these patients and determined whether something is different or not – so far we haven’t seen severe cases or fatalities.”
William Hanaj, an epidemiologist at the Harvard TH Chan School of Public Health and co-director of its Center for the Dynamics of Infectious Diseases, says the strain appears to be closely linked to what circulated in West Africa in 2018, but more research is needed.
“It certainly behaves differently in the sense that it’s much more common. “Until recently, there were a handful of countries outside of Africa where he was introduced,” he told CBC News.
“Obviously something different is happening here. What makes that difference is currently unknown.”
Hanaj said the current strain, which is circulating in at least 11 countries, including Canada, appears to be more transmissible, with reproductive number probably more than one, given that the global epidemic continues to grow at an unknown rate.
But cases can also quietly spread below the surface for months.
Negative spot micrography shows a particle of the mulberry virus. The speed with which cases of monkeypox are detected worldwide signals a major change in the behavior of the virus and its ability to spread from person to person unnoticed. Record (CDC)
“As soon as the places started looking for it, they found it, which suggests that it is not spreading very fast, but that it has been there for some time in relatively large quantities,” he said. “Once you start targeting your tests to these distinctive lesions, you start finding it.”
IN genomic sequence of one of the first cases of monkeypox identified in Portugal was uploaded on Friday after the sample was received on May 4, but Hanaj said it was “very reasonable” to suspect that the outbreak “significantly precedes” the case.
“We do not know the true number of cases, but I think it is important to keep in mind that this can be transmitted for months and has not been noticed,” he said.
“Human behavior has also moved back and forth between some rather extreme conditions over the last few years, and we are now in a situation where this virus is likely to be more easily transmitted.
“How is it transmitted?”
Canada’s chief public health director, Theresa Tam, said Friday that genomic sequencing is currently underway at the National Microbiology Laboratory in Winnipeg to confirm more cases in the coming days and weeks.
“In fact, we do not know the extent of the spread in Canada. It is under active investigation,” she told a news conference on Friday.
“So far, we know that not many of these people are involved in travel to Africa, where the disease is usually observed. So it’s unusual … to see so many cases reported in different countries outside of Africa. ”
He said at the beginning of each epidemic that experts needed to “deploy the web” to try to understand the ways the virus was transmitted, adding that much remained unknown about the “unusual situation”.
“There have probably been some hidden chains of transmission that could emerge in quite a few weeks, given the global situation we are seeing at the moment,” she said.
“Most people haven’t traveled, so how do you surrender?”
The hands of a monkey measles patient from Lodge, Democratic Republic of the Congo, were seen during an investigation in 1997 (Brian WJ Mahy / CDC / Handout via Reuters)
Hanaj says the most important factor in determining whether an outbreak like this is controlled is whether symptoms appear before or after a person becomes infected.
“If a person is infected before they develop symptoms, it is very difficult to control,” he said, “with poxviruses, classic, this is not the case. So a person develops a rash and just at that moment becomes infectious.”
“It simply came to our notice then. But we have every reason to suspect it will be, but we still have to confirm it. “
Change in distribution among people
Another unusual feature of the cases of monkeypox that are currently spreading around the world is the lack of transmission directly from animals to humans.
“There has been very little evidence of human-to-human transmission, certainly outside of Africa, so far,” Hanaj said. “It looks a lot like this is a line that has developed the ability to transmit from person to person. How? I don’t know. Where? I have no idea.”
Hanaj says another concern is all patients who unknowingly develop mild symptoms but may still be contagious and may not realize they are at risk for others.
Angela Rasmussen, a virologist and researcher at the University of Saskatchewan’s Organization for Vaccines and Infectious Diseases (VIDO), says that monkeypox is usually spread by close contact and inhalation – though not as easily as viruses such as SARS-CoV-2.
But it can also be spread through direct and indirect contact, she said.
“This means that there are many opportunities for its spread in situations where people are in close contact.
WATCH Cases of monkeypox found in Canada amid global outbreak:
Alleged cases of monkeypox found in Canada amid global epidemic
Experts are urging people not to panic over a handful of suspected cases of monkeypox being investigated in Quebec. This is because infections seem to spread in several countries through close contact with others.
“Any cause for concern” about the restriction
Rasmussen says there are many ways in which smallpox outbreaks can be controlled through classic epidemiological measures, such as tracking contacts, isolating infected people and quarantining those who may have been exposed.
If that doesn’t happen, “we don’t have a vaccine,” she said. “We also have drugs that could be used that would certainly help limit them.”
Deputy Chief Public Health Officer Dr Howard Nju said on Friday that after Canada stopped smallpox vaccination campaigns in the early 1970s, those under 50 will have no protection as long as immunity the older Canadians have probably lost weight.
A microscopic view of skin tissue collected from a lesion on the skin of a monkey that has been infected with the monkeypox virus can be seen in a 1968 photograph (Handout / Reuters)
“In general, the entire population is susceptible to monkeypox,” Nju said during a news conference.
The British health authorities took a bold step this week and moved to offer smallpox vaccines, which are somewhat effective against monkeypox, to some health professionals and contacts who may have been exposed – using the so-called ring vaccination strategy.
“There is every reason to worry about limiting capacity, not least because the weight of the insulation will depend on the vaccines and their very effective use,” Hanaj said.
“And the bigger the problem, the worse the position we start from. So I think it’s unlikely to be easy to master, but …
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