Bats, a symbol of Halloween, may be responsible for canceling it this year.The coronavirus that has grounded trick-or-treaters likely came from bats.These creatures of the night have evolved a spooky ability to harbor a number of viruses that can kill humans — without getting sick themselves.How they do it may hold the key to immortality — or a longer life, anyway.Guilt by associationThough there is no smoking gun showing that the coronavirus causing the COVID-19 pandemic came from bats, the virus is closely related to several others they harbor.Bats also are known to carry rabies and the Marburg hemorrhagic fever virus, and they are lead suspects as the source of Ebola and the 2003 severe acute respiratory syndrome, or SARS.It sure seems like they carry a lot of nasty viruses.But “maybe we just have a lot of bat viruses because there’s lots of bats,” said University of Glasgow researcher Daniel Streicker.Sorry, but your browser cannot support embedded video of this type, you can
download this video to view it offline.Download File360p | 9 MB480p | 13 MB540p | 16 MB720p | 32 MB1080p | 66 MBOriginal | 82 MB Embed” />Copy Download AudioThere are roughly 1,400 different species around the world, Streicker noted, second only to rodents, which also carry a lot of diseases.”It isn’t the bats. They figured out how to deal with their viruses,” University of Saskatchewan microbiologist Vikram Misra said.Taking offTheir virus-resisting powers may be an unexpected byproduct of evolving to fly.Flying requires a tremendous amount of energy. Generating that energy also produces toxic byproducts that can damage cells.Normally, cell damage would trigger inflammation, the immune system’s first line of defense. The same inflammatory response kicks in whether the damage comes from toxic molecules, injury or infection. As part of the response, the body mobilizes cells to the damaged area that can blast germs or infected cells.Too much inflammation can kill. Overactive inflammatory responses are what lead to lung damage, blood clots and other fatal complications in COVID-19 patients.”Maybe bats had to down-regulate their responses just not to get inflamed every time they had to fly,” said University of Rochester biology professor Vera Gorbunova.But flight “doesn’t explain everything about bats,” she said. Another reason their immune systems are different from most mammals may be because of the way they live.Bats live in colonies that can number in the millions of individuals, roosting shoulder to shoulder. Diseases could spread quickly in those close quarters.”They probably evolved defenses because they’re exposed to a lot of viruses,” Gorbunova said.Delicate balanceFor whatever reason, their adaptations appear to be so important that they evolved independently in different bat species, a new study shows.Turning down a key immune response would seem to leave bats open to infection. But evolution has turned up another line of defense that targets viruses.Bats and viruses may have reached a “wonderfully balanced relationship where viruses don’t cause diseases and bats don’t get rid of the viruses,” Misra said. He and his colleagues at the University of Saskatchewan have found that bat cells can remain infected for months.But stress — from humans encroaching on their habitat or capturing them to sell at live-animal markets — may disrupt that relationship.”If you upset this delicate balance in such a way that the viruses now have an upper hand,” Misra said, “then the viruses start to multiply and the bats now start to shed more of these viruses. We think that that may be one of the reasons why spillovers occur” and the viruses jump into another species.”We can’t say for sure that that’s the case,” he added, but he and his colleagues are testing the idea now.Live long and prosperAside from reaching a detente with viruses, bats may have reaped another unintended reward from learning to fly. They may have discovered the fountain of youth.Bats live disproportionately long and healthy lives for their size. Take North American little brown bats, which are “about the size your thumb,” Misra said.”Normally, you would expect them to live maybe two years, three years, if you compare them to animals that are of comparable size,” he said. “These bats live 30 or 40 years.”The key may be their ability to tamp down inflammation without leaving themselves exposed to viruses.”Inflammation may be the driving force of age-related diseases,” biology professor Gorbunova said. It is a factor in Alzheimer’s disease, some forms of heart disease, diabetes and many others.With more research, she added, perhaps the bats that seem to be responsible for so much suffering can someday help us live longer.
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Globally, COVID-19 cases have exceeded 45 million and nearly 1.2 million people have succumbed to the virus, according to the latest data. VOA correspondent Mariama Diallo reports on countries with the highest number of cases, the US, India and Brazil, respectively.
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Colorado’s flagship university is getting a head start spotting COVID-19 outbreaks among students at residential dorms — by testing the wastewater.Cresten Mansfeldt, an engineering professor at University of Colorado-Boulder, heads out with students to start an early warning system on the campus for SARS COV-2 — the virus that causes COVID-19. The warning system involves a plastic bin and what can be found below a sewage manhole.As for the project’s name…“Well, we call our project ‘Project Half-Shell,’ because it’s an homage to the Teenage Mutant Ninja Turtles,” Mansfeldt says. “Hanging out in the sewers.”Mansfeldt’s team all wear masks to guard against COVID-19. Plus, they’re dressed for dirty work, in overalls and work gloves. There’s some heavy lifting up ahead, too. That manhole cover weighs over 100 kilograms. Mansfeldt lifts the lid then points a flashlight into the hole. Ten feet underground, a concrete ditch carries a glistening stream of sewage water.’Domestic wastewater'”So, what’s flowing through here is actually domestic wastewater,” Mansfeldt says. “Things we send down the drain either through the toilets or through showers or laundry systems. Basically, any drains that are coming out, end up flowing into these river networks that exist underneath most municipalities and cities.”“Here,” he said, “we’re most interested in what’s coming out of the toilets. In feces, because that seems to be where individuals can shed the SARS COV-2 virus here.”Engineering student Jessica Darby says checking wastewater this way gives an early warning about COVID-19 infections.“COVID is in your intestines,” she says. “And so even if you don’t have symptoms, or before it actually is more of a disease or infection, it can be found in your intestines. So if you shed it into the sewer system, you can kind of determine if people have it, even if it’s before they have symptoms, or if they don’t ever have symptoms.”To test this dorm’s wastewater for COVID-19, Mansfeldt’s team unlocks a large plastic bin that’s beside the manhole. Inside is a 2-liter jerry can and some very long tubes. The team snakes the tubes down until they touch the sewage water. Back inside the plastic tub, they switch on a little pump.Once each day, the Project Half-Shell team will unlock the tub and take a few vials of wastewater over to the lab, to screen an entire dorm for COVID-19.An early warningMansfeldt says that testing wastewater this way saves on testing time and testing supplies.“A single sample here is reflective of hundreds of people’s contribution,” he says.Earlier this fall, data from the team warned the campus about a rising spike in COVID-19 cases. Individual saliva tests of dorm residents then identified who was sick, and it was quite a few.“This led the administration to actually invoke some of the social-distancing options that were available,” Mansfeldt says.Two weeks later, data showed the restrictions could be relaxed.Wastewater testing can also provide an early warning in countries that have cholera and polio. As for COVID cases in the U.S., Mansfeldt says that in addition to screening college dorms, some communities are also screening sewers for early signs of SARS-COV2 outbreaks at nursing homes and schools.
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Researchers say a rare type of meteor recovered nearly three years ago from a frozen lake in the U.S. state of Michigan has offered one of the best glimpses yet into the organic compounds such objects carry.A study published in the journal Meteoritics & Planetary Science tells the story of a bright meteor, also known as fireballs for how they light up the night sky, that fell in January 2018.Researchers say the meteors that shine with such brightness are usually larger and have traveled farther into Earth’s atmosphere without breaking up, raising hopes pieces could be recovered. Using weather radar, they were able to track the meteor’s trajectory, discovering large pieces just two days after it hit a frozen lake.University of Chicago researcher Philipp Heck said finding the meteorite (what a meteor is called once it lands on Earth) pieces so quickly and on a frozen lake was significant. He said meteors often fall into dirt or water, and if they are not discovered quickly, they can be contaminated by organic Earth material.The researchers determined they’d found an “H4 chondrite” meteorite. Only 4% of all meteorites falling to Earth are of this type, at least in recent history. Heck said it had “a rich inventory of extraterrestrial organic compounds,” which contain carbon, one of the basic ingredients of life on Earth.The discovery adds evidence to the widely held theory that compounds such as these — the so-called building blocks of life — were delivered to Earth by similar meteors shortly after Earth formed.Heck said the discovery of the Michigan meteor and subsequent analysis also helped scientists develop new analytical techniques to study meteors of its kind and gain knowledge that can be shared with other scientists around the world.
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A rising tide of new coronavirus cases worldwide is forcing leaders to consider new lockdown measures to contain an increase in infections.
 
British Foreign Minister Dominic Raab said in an interview with BBC television Friday a national lockdown in his country is not inevitable to prevent the further spread of the disease, adding that a localized approach would be efficient if rules for each area were strictly observed.
 
Raab’s statment followed announcements by leaders of France and Germany earlier in the week to impose new lockdowns.
 
French President Emmanuel Macron announced a nationwide monthlong lockdown that will take effect Friday. Macron said restaurants, bars, cafes and other nonessential businesses will be closed, while citizens will only be allowed to leave their homes for work, shopping and doctor appointments.
 German Chancellor Angela Merkel attends a debate about German government’s policies to combat the spread of the coronavirus and COVID-19 disease at the parliament Bundestag, in Berlin, Germany, Thursday, Oct. 29, 2020. (Photo/Markus Schreiber)German Chancellor Angela Merkel announced a set of similar measures in her own month-long lockdown which takes effect Monday. In addition to restaurants and bars, all gyms, theaters and opera houses will be shut down under Merkel’s order, while the majority of businesses, shops and hair salons will be allowed to remain open.  
 
Schools in both nations will remain open during their respective lockdowns.  
The restrictions were announced by Macron and Merkel as both nations struggle with a record number of new COVID-19 cases practically every day.
 
France and Germany joined several other European nations that have been forced to impose a new set of restrictions to deal with a second and growing wave of the virus as the cold weather season approaches in the Northern Hemisphere.
 
Ukraine reported Friday a record 8,312 new COVID-19 cases in the previous 24 hours, up from the October 23 high of 7,517, with total infections at 378,729. The deaths also jumped by a record 173, for a toll of 7,041.
 
In Japan, the health ministry said Friday that the coronavirus cases topped 100,000, nine months after the first case was reported in mid-January. Japan has more than 1,700 deaths.
 
As of early Friday, there are more than 45 million total COVID-19 cases worldwide, including over 1.18 million deaths. India has reached the milestone of over 8 million total novel coronavirus cases, second only to the United States, with 8.94 million total confirmed cases.
 
As the effort to develop a safe and effective vaccine continues, U.S. President Donald Trump’s administration said it would ensure that everyone in the United States will be able to be inoculated free of charge. 
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Ecological destruction and unsustainable consumption have entered humanity into an “era of pandemics,” according to a new report.”Without preventative strategies, pandemics will emerge more often, spread more rapidly, kill more people, and affect the global economy with more devastating impact than ever before,” says the report from the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, a global expert body advising governments.The authors say roughly $50 billion per year in pandemic prevention would spare the world about $1 trillion per year on average in economic damage, not to mention the toll in human suffering.The report suggests ways to shift the focus to prevention, rather than trying to contain pandemics after they happen.SpilloverAs of July, COVID-19’s economic toll was at least $8 trillion and counting, the authors say.It’s just the latest costly emerging infectious disease, following HIV/AIDS, SARS, Ebola, Zika, H1N1 swine flu and others.All of these deadly diseases originated in animals before “spilling over” into humans. Nearly three-quarters of all emerging diseases have animal origins. And there are hundreds of thousands more possibly infectious viruses that have not been discovered yet, the report notes.But don’t blame the animals. The rate of spillover has increased because of human activities.COVID-19 is a prime example of the problem, the authors say. The coronavirus that causes the disease likely emerged from bats in China, where expanding human populations are increasingly encroaching on wildlife habitat. It probably spread through the wildlife trade, at a market where vendors sell wild animals for food and medicine.Deforestation, agricultural expansion, urbanization and other land-use changes are responsible for about a third of all new diseases to emerge since 1960, the report says. The $100 billion-plus global wildlife trade is also responsible for the spread of new and existing diseases and is a threat to biodiversity.Not too lateHowever, “this is not a doom and gloom report saying the world’s going to end and it’s too late,” said report author Peter Daszak, president of EcoHealth Alliance, a global health, conservation and development organization. “This is an optimistic call for action.”The current strategy to deal with pandemics is to wait for them to emerge and try to identify them before they spread, Daszak said.COVID-19 has demonstrated the flaws in that plan. Chinese authorities tried to contain it after the disease emerged late last year, but it was too late.”And here we are waiting for a vaccine and drugs to work,” Daszak said. “It’s not a good strategy. We need to do more.”The report calls for “transformative change towards preventing pandemics.”Some of that change needs to come from consumers.One change involves eating meat.Demand for meat drives increased pandemic risk in two ways, the report says. Feeding food animals is a major driver of deforestation. Also, intensive animal agriculture, which packs many animals into small spaces, often in close proximity to people, makes it easy for germs to jump species.”We can continue to eat meat,” Daszak said, “but we need to do it in a way that is far more sustainable if we want to get rid of pandemics.”The report suggests taxes on meat or livestock or other ways to incorporate the costs of pandemics into the price of production and consumption.Consumers also can drive change by pressuring companies to reduce deforestation, for example.”Global for-profit companies care about what we, the public, think about them,” Daszak said. “They respond when people call them out.”Government policy should focus on pandemic prevention as well, the authors say.Emerging-disease risk should be factored into any large-scale land use planning. Wildlife trade enforcement should focus on reducing or removing species at high risk of spreading diseases. And increased disease monitoring should focus on the links between human health, animal health and the environment, known as the One Health approach.All these suggestions, he noted, are “easy to say, really difficult to do.”These measures and others would cost about $40 billion to $58 billion per year, the report says.But with the bill for pandemics averaging a trillion dollars per year, Daszak said, “an ounce of prevention is worth a hundred pounds of cure.”
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The White House Coronavirus Task Force warned Thursday of an “unrelenting” spread of the virus, particularly across the western half of the country, Reuters reported. Members of the task force are reportedly pushing for aggressive measures to quell the spread of the virus.The United States has confirmed more than 8.9 million cases of COVID-19 and recorded more than 228,000 deaths as of Thursday, according to data from the Johns Hopkins University Coronavirus Resource Center.”We continue to see unrelenting, broad community spread in the Midwest, Upper Midwest and West. This will require aggressive mitigation to control both the silent, asymptomatic spread and symptomatic spread,” said the task force’s report to one state, according to CNN. The task force’s most prominent member, Dr. Anthony Fauci, told CNBC Wednesday that the coronavirus outbreak in the U.S. is “going in the wrong direction.” “If things do not change, if they continue on the course we’re on, there’s going to be a whole lot of pain in this country with regard to additional cases and hospitalizations, and deaths,” Fauci said, noting that case numbers were rising in 47 states.At least seven states reported record one-day case increases Thursday, according to Reuters.
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Virologists at the University of Tokyo say that while masks can offer protection from airborne COVID-19 particles, their effectiveness varies. VOA Correspondent Mariama Diallo has more on the results of the new research.
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The World Meteorological Organization predicts La Nina will continue through January and is expected to usher in drier and wetter conditions than normal in different parts of the world.The latest seasonal forecasts indicate the La Nina event will cause drier than normal conditions in much of East Africa and lead to increased rainfall in southern Africa. Central Asia is likely to see below normal rainfall earlier than usual.The WMO reports some of the Pacific islands and the northern region of South America will see some of the most significant precipitation anomalies associated with this year’s La Nina event — a cooling of ocean surface water along the Pacific coast of the South American tropics that occurs on average every two to seven years.Some countries and regions are particularly vulnerable to changes in weather patterns.WMO humanitarian expert Gavin Iley told VOA the Greater Horn of Africa was an area of particular concern.“As we know, it is already being beset by problems, with locust infestation,” Iley said. “And generally, the models are suggesting below normal rainfall for quite a large portion of the Greater Horn of Africa. So, obviously that could have a number of impacts … in areas like Somalia. … So, we always need to keep an eye on the latest outlook.”WMO said governments can use weather forecasts to plan ways to reduce adverse impacts in climate-sensitive sectors like agriculture, health, water resources and disaster management.WMO Deputy Director of Climate Services Maxx Dilley said governments can use La Nina forecasting to adapt their strategies to the changing weather patterns.“You can imagine in the agricultural sector that some crops will do well under wet conditions and others will do better under dry conditions,” Dilley said. “And there are agricultural management practices that can be adjusted to take account of whether it is expected to be wet or dry.”Dilley said WMO increasingly is trying to tailor these forecasts to specific concerns, such as food security or human health. For example, he said, wet conditions alone do not provoke outbreaks of dengue fever or malaria. He said temperature, humidity and vegetation create the conditions for mosquitoes to breed.So, rather than just giving a rainfall forecast, he said, meteorologists will provide a forecast that is correlated with these diseases and can be used for dengue fever or malaria control.
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German Chancellor Angela Merkel Thursday defended new coronavirus restrictions to lawmakers and lashed out at those who tried to dismiss the infection as harmless as the number of cases hit a new high.
In a speech before the Bundestag – the German parliament – that was interrupted by heckling from right-wing politicians, Merkel said the new measures “are appropriate, necessary and proportionate.” She said, “There is no other milder approach than reducing personal contacts to try and stop the infections chain and to change the course of the infections back to a level where we can handle it.”  
Merkel spoke a day after she and the governors of Germany’s 16 states agreed on far-reaching restrictions to curb the spread of the virus, including the closure of bars and restaurants, limits on social contacts and bans on concerts and other public events.
But, as in most countries around the world, there has been pushback against such restrictions. There have been protests and reports of violence in some areas by those claiming the dangers of the virus have been overstated and restrictions are nothing more than a power grab.
When heckling broke out from populist politicians during Merkel’s speech, Bundestag President Wolfgang Schauble warned there would be consequences for their actions if they did not let the chancellor continue.
Merkel responded by lashing out at those who claim the virus is harmless, saying, “Lies and disinformation, conspiracy theories and hate, damage not only democratic debate but also the fight against the virus.”
She said, “When science has proven something is false then it must be clearly stated. Because our relation to facts and information not only affects democratic debate but human lives.”
Merkel told lawmakers that Germany is in a “dramatic situation” as it goes into winter, which she said would be “four long, difficult months. But it will end.”
Germany’s disease control center said local health authorities reported 16,774 new positive tests in the past day, pushing the country’s total since the start of the outbreak close to half-a-million.
The Robert Koch Institute recorded 89 additional deaths, taking Germany’s toll to 10,272.
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The World Health Organization warns nearly 18 million people in Yemen are unable to get treatment for deadly diseases because years of war, economic distress and a chronic shortage of money have led to a collapse of the country’s healthcare system. More than five years of escalating conflict have devastated Yemen’s economy and ability to provide enough food and medical care to keep its population healthy.  World Health Organization officials report only half of the country’s health facilities are fully functioning.  And those that remain open suffer from severe shortages of qualified staff, essential medicines and supplies.WHO spokesman Tarik Jasarevic says that for three years, appalling socio-economic conditions in Yemen have caused a spiraling of deadly diseases including the worst cholera outbreak in modern times, as well as epidemics of diphtheria, dengue, measles and malaria.FILE – Mourners lower the body of a man, suspected to have died from the coronavirus disease (COVID-19) in Taiz, Yemen, June 25, 2020.“Now we have also COVID-19 and, unfortunately, we have cases of polio coming back to Yemen after it has been declared as a polio-free country,” Jasarevic said. “And, for people who have chronic diseases, such as cancer, diabetes, or others, the treatment is limited.”   WHO reports 2,065 confirmed cases of COVID-19, including more than 600 deaths.    It notes two new cases of vaccine derived cases of polio have been confirmed.  The outbreak of this extremely contagious disease has paralyzed 17 children.  Jasarevic says armed conflict and political instability have disrupted the delivery of essential healthcare supplies.  He tells VOA the Sanaa International Airport has not been in operation since September 9th and this is a major obstruction in efforts to respond to COVID-19 and other diseases.“According to our office there, this has delayed arrival of COVID-19 experts, the arrival of critical medical but also other humanitarian supplies that include 207 tons of COVID-19 response equipment,” Jasarevic said.UN: Child Malnutrition Soars in War-torn Yemen20% of children are malnourished and need urgent treatmentJasarevic says WHO is critically short of money to fund its humanitarian operation.  He says the agency has received less than half of the $164.5 million it needs.  Unless money is urgently received, he warns nine million people will lose access to basic health care services by the end of the year.In addition, he says as many as 18 million people, including six million children will be deprived of the life-saving vaccines to immunize them against deadly diseases such as measles and polio.
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Europe is once again an epicenter of the COVID-19 pandemic and Spain – under a state of emergency – has gone into another lockdown as protests continue.  Alfonso Beato has more from Barcelona in this report narrated by Roderick James.Camera: Alfonso Beato   Producer: Roderick James
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European Commission President Ursula von der Leyen said Wednesday the EU’s administrative arm will spend $117 million on rapid COVID-19 tests as the virus surges across Europe.
 
Speaking to reporters in Brussels, Von der Leyen said unlike last spring, when the pandemic first began, every European country is feeling the effects of a second wave of the virus. The European Center for Disease Prevention and Control says the virus continues to spread throughout the continent.
 
The agency reports almost 6.5 million people have contracted the virus in the EU member countries, plus Britain, Iceland, Liechtenstein, Norway and Switzerland.
 
Von der Leyen says they are purchasing rapid antigen tests as another tool to help bring COVID-19 under control. The finger-prick antigen tests are not considered to be as reliable as the standard nasal-swab “PCR test,” but they work much more quickly, with results available at the testing point within 15 minutes.  
 
European health experts say the virus is now moving too quickly to rely on tests that can take days.
 
Von der Leyen also urged member state leaders to improve information-sharing about the virus, saying that will help identify where extra intensive care unit capacity might be found and better organize cross-border patient care.
 
Von der Leyen also called on member states to begin preparing national vaccination plans, and to review them now at the EU level. She said they all need to be prepared for the arrival of the first vaccine, which in the best-case scenarios could begin arriving sometime in April in monthly 20 million to 50 million dose deliveries. 
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Iran’s parliament speaker said that he has tested positive for the coronavirus, joining a growing list of infected Iranian officials as the country again shattered its single-day death record with 415 new fatalities reported Wednesday.
Mohammad Bagher Ghalibaf tweeted that he received the news after one of his colleagues tested positive for the virus. He said he would continue to carry out his duties from self-quarantine. Earlier this month, he was on state TV visiting a coronavirus ward in one of capital’s overwhelmed hospitals to show support.
“I decided to appear in the hospital to see problems from a close distance,” Ghalibaf told local media from the ward in Tehran. “Supervising is the main duty of parliament.”
Iran has for months wrestled with the worst outbreak in the Middle East, and on Wednesday the daily death toll hit a new high for a second consecutive day. Wednesday’s count pushes Iran’s total death toll past 33,700 — the highest in the region. Public health officials have repeatedly stressed that the true number of deaths is likely 2.5 times higher.
The government, desperate to salvage an economy reeling from severe American sanctions, has been loath to order business closures even as infection rates reach new heights.
In a clear sign of the outbreak’s scale, dozens of top officials have fallen ill. At least 30 lawmakers have tested positive in recent months, according to local media, and a senior adviser to the country’s supreme leader has died. Earlier this month, the head of the country’s atomic energy organization and the vice president in charge of budget and planning both contracted the virus.
Iran’s former parliament speaker, Ali Larijani, tested positive for the virus in April and returned to work after convalescing for three weeks. Ghalibaf took over his post in early June.
As infections surge, filling the country’s hospitals and driving up its death toll, Iran’s parliament has continued to hold regular sessions. Lawmakers wear masks but tend not to practice social distancing. When President Hassan Rouhani decided to skip a parliamentary vote this fall out of concern for his health, he faced intense backlash from hard-line lawmakers who demanded he attend regardless.
The timing of the pandemic has proved disastrous for Iran’s economy, which is buckling under U.S. sanctions re-imposed in 2018 after the Trump administration withdrew from the nuclear deal between Iran and world powers.
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A new study of the British population shows that antibodies in the human body fighting COVID-19 declined rapidly in the British population during the summer, suggesting any immunity against the virus may not last long.The study, conducted by Imperial College London and published Tuesday, involved tests on more than 365,000 British people between June 20 and Sept. 28.In their findings, the researchers’ analysis of the home finger-prick tests found that the number of people testing positive for antibodies dropped by 26.5% during the study period, from almost 6% to 4.4%.The findings suggest the possibility of decreasing population immunity ahead of a second wave of infections in recent weeks that has forced local lockdowns and restrictions.The researchers say it is unclear what level of protection antibodies give a person against COVID-19 specifically.Imperial College London Department of Infectious Disease head, Wendy Barclay, told reporters in London they are confident in what a decline in antibodies tells them.“On the balance of evidence, I would say with what we know for other coronaviruses, it would look as if immunity declines away at the same rate as antibodies decline away, and that this is an indication of waning immunity at the population level.”The researchers say that more than anything, the study reinforces the need for a vaccine to effectively bring the virus under control.  
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