<div data-thumb="https://scx1.b-cdn.net/csz/news/tmb/2020/theunusualsu.jpg" data-src="https://scx2.b-cdn.net/gfx/news/2020/theunusualsu.jpg" data-sub-html="This study established the identity of the new coronavirus by sequencing its genome for the first time. Credit: Chinese Medical Journal“>
This study established the identity of the new coronavirus by sequencing its genome for the first time. Credit: Chinese Medical Journal
In early December, a few people in the city of Wuhan in the Hubei province of China began falling sick after going to a local seafood market. They experienced symptoms like cough, fever, and shortness of breath, and even complications related to acute respiratory distress syndrome (ARDS). The immediate diagnosis was pneumonia, but the exact cause was unexplained. What caused this new outbreak? Is it the severe acute respiratory syndrome (SARS)-CoV? Is it the Middle East respiratory syndrome (MERS)-CoV?
As it turns out, scientists had undertaken a study to identify this virus in December after analyzing the first few cases. This study is now published in Chinese Medical Journal and the identity of the virus has been established—it is a completely new virus, closely related to the bat SARS-like CoV. Dr. Jianwei Wang (Chinese Academy of Medical Sciences, Institute of Pathogen Biology), lead researcher on the study, states,”Our paper has established the identity of the bat-origin CoV that was unknown until now.”
In this study, scientists from renowned research institutes in China, such as the Chinese Academy of Medical Sciences, Institute of Pathogen Biology, China-Japan Friendship Hospital, and Peking Union Medical College, jointly discovered and identified the new CoV—the main culprit of the Wuhan outbreak—by next generation sequencing (NGS). They focused on five patients admitted to Jin Yin-tan Hospital in Wuhan, most of whom were workers in the Huanan Seafood Market in Wuhan. These patients had high fever, cough, and other symptoms, and were initially diagnosed to have pneumonia, but of an unknown cause. Some patients’ condition rapidly worsened to ARDS; one even died. Dr. Wang says, “Chest x-rays of the patients showed some hazy opacities and consolidations, which are typical of pneumonia. However, we wanted to find out what caused the pneumonia, and our subsequent experiments revealed the exact cause—a new CoV that was not known before.”
For the study, the scientists used bronchoalveolar lavage (BAL) fluid samples taken from the patients (BAL is a procedure in which sterile fluid is transferred to the lungs through a bronchoscope and then collected for analysis).
This pioneering study undertakes the sequencing of the CoV’s genome for the first time. Credit: Chinese Medical Journal
First, the scientists attempted to identify the virus by genome sequencing, using NGS technology. NGS is the preferred screening method for identifying unknown pathogens because it quickly detects and rules out all known pathogenic microorganisms in the sample. Based on sequencing of the DNA/RNA from the BAL fluid samples, the scientists found that most of the viral reads belonged to the CoV family. The scientists then assembled the different “reads” that belonged to CoVs and constructed a whole genomic sequence for the new virus; these sequences were 99.8-99.9% similar among all the patients’ samples, confirming that this virus was the common pathogen in all the patients.
Further, using homology analysis, where a genome sequence is compared against other known genome sequences (with a preset threshold of 90% for it to be considered a “new” sequence), they confirmed that the genome sequence of this new virus is 79.0% similar to the SARS-CoV, about 51.8% similar to the MERS-CoV, and about 87.6-87.7% similar to other SARS-like CoVs from Chinese horseshoe bats (called ZC45 and ZXC21). Phylogenetic analysis showed that the sequences of the five CoV strains obtained were closest to those of bat-derived strains, but formed separate evolutionary branches. These findings clearly suggest that the virus originated from bats. Dr. Wang states, “Because the similarities of the viral replicase gene with all other known ‘similar’ viruses are still less than 90%, and also taking into account the phylogenetic analysis results, we consider that this is indeed a new, previously unknown CoV. This new virus is temporarily called the 2019-nCoV.”
Lastly, the scientists moved to ‘isolating’ the virus from the BAL fluid samples by checking whether the fluid samples showed cytopathic effect to cell lines in the laboratory. The cells exposed to the fluid samples were observed under an electron microscope, and the scientists found characteristic CoV-like structures. They also used immunofluorescence—a technique that uses specific antibodies tagged with fluorescent dyes. For this, they used serum from the recovering patients (which contained antibodies), which reacted with the viral particles inside the cells; this confirmed that this virus was indeed the cause of the infection.
This study paves the way for future studies to understand the virus and its sources better, especially given its rapid spread, its ability to cause fatal ARDS, and the panic caused by the outbreak. Although 4 of the 5 patients from whom this virus was identified were from a seafood market in Wuhan, the exact origin of infection is unknown. The CoV could have been transmitted to humans through an “intermediate” carrier, such as in the case of SARS-CoV (palm civet meat) or MERS-CoV (camel). Dr. Wang concludes, “All human CoVs are zoonotic, and several human CoVs have originated from bats, including the SARS- and MERS-CoVs. Our study clearly shows the urgent need for regular monitoring of the transmission of bat-origin CoVs to humans. The emergence of this virus is a massive threat to public health, and therefore, it is of critical importance to understand the source of this virus and decide the next steps before we witness a larger scale outbreak.”
More information:
Li-Li Ren et al, Identification of a novel coronavirus causing severe pneumonia in human, Chinese Medical Journal (2020). DOI: 10.1097/CM9.0000000000000722
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Chinese Academy of Medical Sciences
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The (un)usual suspect—novel coronavirus identified (2020, February 18)
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The Canadian government says it will donate up to 200,000 vaccine doses to fight the mpox outbreak in Congo and other African countries.
It says the donated doses of Imvamune will come from Canada’s existing supply and will not affect the country’s preparedness for mpox cases in this country.
Minister of Health Mark Holland says the donation “will help to protect those in the most affected regions of Africa and will help prevent further spread of the virus.”
Dr. Madhukar Pai, Canada research chair in epidemiology and global health, says although the donation is welcome, it is a very small portion of the estimated 10 million vaccine doses needed to control the outbreak.
Vaccine donations from wealthier countries have only recently started arriving in Africa, almost a month after the World Health Organization declared the mpox outbreak a public health emergency of international concern.
A few days after the declaration in August, Global Affairs Canada announced a contribution of $1 million for mpox surveillance, diagnostic tools, research and community awareness in Africa.
On Thursday, the Africa Centres for Disease Control and Prevention said mpox is still on the rise and that testing rates are “insufficient” across the continent.
Jason Kindrachuk, Canada research chair in emerging viruses at the University of Manitoba, said donating vaccines, in addition to supporting surveillance and diagnostic tests, is “massively important.”
But Kindrachuk, who has worked on the ground in Congo during the epidemic, also said that the international response to the mpox outbreak is “better late than never (but) better never late.”
“It would have been fantastic for us globally to not be in this position by having provided doses a much, much longer time prior than when we are,” he said, noting that the outbreak of clade I mpox in Congo started in early 2023.
Clade II mpox, endemic in regions of West Africa, came to the world’s attention even earlier — in 2022 — as that strain of virus spread to other countries, including Canada.
Two doses are recommended for mpox vaccination, so the donation may only benefit 100,000 people, Pai said.
Pai questioned whether Canada is contributing enough, as the federal government hasn’t said what percentage of its mpox vaccine stockpile it is donating.
“Small donations are simply not going to help end this crisis. We need to show greater solidarity and support,” he said in an email.
“That is the biggest lesson from the COVID-19 pandemic — our collective safety is tied with that of other nations.”
This report by The Canadian Press was first published Sept. 13, 2024.
Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.
HALIFAX – The Nova Scotia government says it could be months before it reveals how many people are on the wait-list for a family doctor.
The head of the province’s health authority told reporters Wednesday that the government won’t release updated data until the 160,000 people who were on the wait-list in June are contacted to verify whether they still need primary care.
Karen Oldfield said Nova Scotia Health is working on validating the primary care wait-list data before posting new numbers, and that work may take a matter of months. The most recent public wait-list figures are from June 1, when 160,234 people, or about 16 per cent of the population, were on it.
“It’s going to take time to make 160,000 calls,” Oldfield said. “We are not talking weeks, we are talking months.”
The interim CEO and president of Nova Scotia Health said people on the list are being asked where they live, whether they still need a family doctor, and to give an update on their health.
A spokesperson with the province’s Health Department says the government and its health authority are “working hard” to turn the wait-list registry into a useful tool, adding that the data will be shared once it is validated.
Nova Scotia’s NDP are calling on Premier Tim Houston to immediately release statistics on how many people are looking for a family doctor. On Tuesday, the NDP introduced a bill that would require the health minister to make the number public every month.
“It is unacceptable for the list to be more than three months out of date,” NDP Leader Claudia Chender said Tuesday.
Chender said releasing this data regularly is vital so Nova Scotians can track the government’s progress on its main 2021 campaign promise: fixing health care.
The number of people in need of a family doctor has more than doubled between the 2021 summer election campaign and June 2024. Since September 2021 about 300 doctors have been added to the provincial health system, the Health Department said.
“We’ll know if Tim Houston is keeping his 2021 election promise to fix health care when Nova Scotians are attached to primary care,” Chender said.
This report by The Canadian Press was first published Sept. 11, 2024.
ST. JOHN’S, N.L. – Newfoundland and Labrador‘s chief medical officer is monitoring the rise of whooping cough infections across the province as cases of the highly contagious disease continue to grow across Canada.
Dr. Janice Fitzgerald says that so far this year, the province has recorded 230 confirmed cases of the vaccine-preventable respiratory tract infection, also known as pertussis.
Late last month, Quebec reported more than 11,000 cases during the same time period, while Ontario counted 470 cases, well above the five-year average of 98. In Quebec, the majority of patients are between the ages of 10 and 14.
Meanwhile, New Brunswick has declared a whooping cough outbreak across the province. A total of 141 cases were reported by last month, exceeding the five-year average of 34.
The disease can lead to severe complications among vulnerable populations including infants, who are at the highest risk of suffering from complications like pneumonia and seizures. Symptoms may start with a runny nose, mild fever and cough, then progress to severe coughing accompanied by a distinctive “whooping” sound during inhalation.
“The public, especially pregnant people and those in close contact with infants, are encouraged to be aware of symptoms related to pertussis and to ensure vaccinations are up to date,” Newfoundland and Labrador’s Health Department said in a statement.
Whooping cough can be treated with antibiotics, but vaccination is the most effective way to control the spread of the disease. As a result, the province has expanded immunization efforts this school year. While booster doses are already offered in Grade 9, the vaccine is now being offered to Grade 8 students as well.
Public health officials say whooping cough is a cyclical disease that increases every two to five or six years.
Meanwhile, New Brunswick’s acting chief medical officer of health expects the current case count to get worse before tapering off.
A rise in whooping cough cases has also been reported in the United States and elsewhere. The Pan American Health Organization issued an alert in July encouraging countries to ramp up their surveillance and vaccination coverage.
This report by The Canadian Press was first published Sept. 10, 2024.
