KT explainer on coronavirus: How long is the Covid-19 pandemic expected to last?

As the Covid-19 case numbers climb rapidly across the globe and as a large population of the world's population remain sheltered in their homes to help limit the spread of the infectious disease, many people, including UAE residents, are asking the obvious question: 'When will all this end?'
Khaleej Times has reached out to seasoned UAE medical professionals who have shared their perspective on this timely question. From understanding the behavioural pattern of large pandemics to herd immunity, doctors have come forward with answers to several pressing questions. Here is what they have to say:
1-How long can we expect this outbreak to last?
Dr Charles Stanford, senior director at VPS Healthcare has said there will be differences between countries depending upon many factors, including age, quarantine and space use, hygiene, etc. "Looking at the published data, some have seen a drop in the numbers after six to eight weeks from the early cases. However, the speed of this drop has been rapid in China but looks much slower in Italy and Spain both still with continued high levels of new patients."
However, Dr Ramanathan Venkiteswaran, a consultant paediatrician and medical director, Aster Hospitals has said it is difficult to predict how long this will last. "With the steps that the Government has put in to increase COVID19 screening and quarantine, we should expect an end to the spread soon," said Venkiteswaran.
Dr Adel Mohamed Yasin Alsisi, the chief medical officer and consultant- Intensive Care at Prime Hospitals said, "In the UAE, the day we have zero new cases, and the remaining cases are all in medical facilities, either in isolation or hospital, we can say the crisis outbreak has been quelled."
2-Researchers have said that large pandemics usually happen in three waves. Can you please explain what that means and how those waves happen?
Dr Maher Balkis, associate staff physician, Infectious Diseases at the Cleveland Clinic Abu Dhabi said, "We have certainly seen outbreaks of flu come in waves. The 1918 Spanish Flu pandemic is notorious for originally has been a small outbreak in the United States before troop movements caused it to spread to other parts of the world."
"The disease curve for that pandemic shows that it wasn't until the second wave of infections that the disease peaked, with the third and final wave being less sever but still more severe than the first. While we do not fully understand these waves of disease, it is generally considered that these waves are due to the disease spreading to new, more vulnerable populations" said Dr Balkis.
"As infections drop to low levels following the initial spike, it is more likely that measures put in place to ease the spread are relaxed, contributing to a new spread of disease," he added.
He added, "Questions remain as to how the Covid-19 pandemic will evolve given that public health oversight and communication between nations is stronger than ever, perhaps helping to keep measures in place for longer to prevent new waves from developing."
3-If pandemics happen in waves, should we be prepared for more periods of school closures, social distancing measures and event cancellations in the coming months?
According to Dr Stanford, governments throughout the world have been blamed for not having prepared for a pandemic.
"In reality, the communities have not been happy to fund the level of essentials required since most of it would have been out of date before the next pandemic. There now needs to be a realistic appraisal of the best way to manage this issue for the current Covid-19 and potential other pandemics," he explained.
However, on the matter of keep schools closed, Dr Stanford said, "Since children are less susceptible or less severe in their reaction to the current virus, it is possible that with the new screening mechanisms schools will not need to be closed unless there is a major recurrence after the quarantine is lifted."
4-When will know a wave is over and will people still need to take infection precautions at that point?
To which, Dr Stanford replied, "The first wave technically is only over when no new patients are found. This will take months but may reduce to manageable levels sooner. In China, the numbers are still grumbling on at low levels - less than 150 per day, a month after reducing from the peak of about 4,000 daily."
However, it is obvious from this that until immunization is possible or the disease completely disappears, everyone still needs to take sensible precautions about hygiene explained Dr Stanford.
"When the numbers of new cases become manageable in a community, there is a need to reduce restrictions to enable the industry to start to produce the essentials for living. This time is a government political decision," he explained.
"The risk is that once movement restrictions are reduced, the numbers of new cases will increase again - a second wave. Common sense about hygiene, spacing at work and school, good contact tracing, and mass screening will help to reduce this risk," he said.
Dr Balkis said, "A wave is considered over when disease activity drops considerably. Once that happens, it is vital that people continue following advice from health authorities to ensure that we do not see a resurgence of the disease. That advice will change based on a number of factors including the availability of vaccines, treatments and numbers of infected people."
Dr Adel Mohamed Yasin Alsisi added, "A wave is considered over when there are no new patients, and the existing patients have been discharged from medical facilities."
5- What can you say about herd immunity?
Dr Venkiteswaran describes herd immunity as a situation when a large percentage of the population becomes immune to a disease, the spread of that disease slows down or stops. "Herd immunity is acquired either due to active or subclinical infection," he said.
Dr Balkis said for herd immunity to happen, a majority of the population must develop immunity towards it either naturally or through vaccination. "Currently, there is no vaccination or approved medication to protect against and treat Covid-19, and since we know very little about how this virus impacts immunity, herd immunity cannot guarantee protection and can lead to many people getting extremely sick," said Dr Balkis.
6-How long do pandemics last?
"Pandemics end once populations reach a 'herd-immunity' threshold. Once people infected with a disease infect less than one other person on average, the spread of the disease is halted. If most people are immune, either through antibodies from a previous infection or through vaccination, the disease dies off in the human population. The more contagious the disease is, the more people need to be immune to stop a pandemic in its tracks," said Dr Balkis.
7-How can the use of contact tracing apps, like the one UAE, has just launched, help the spread of the disease without disturbing user privacy?
Dr Venkiteswaran said the TraceCovid app helps the contact-tracing process by automatically recording all the people who had been near a Covid-19 patient. This helps the authorities to quickly trace and provide the necessary health care for contacts. "This information is shared only when one of the users is tested positive with Covid-19 and should not affect user privacy," he explained.
While Dr Stanford said, "In pandemic situations, a need for an agreed balance between individual privacy and community is necessary. I am sure this will have been discussed. Individuals diagnosed to be infectious will be under healthcare and most people contacted because of risk will probably be glad to be tested. The mechanism is an innovative one and time will tell if it has been successful."
dhanusha@khaleejtimes.com 
 
 

Dhanusha Gokulan

dhanusha@khaleejtimes.com