Federal Government has adopted a “portfolio approach” as directives in ensuring the range of coronavirus vaccines, according to Treasurer Josh Frydenberg.
This comes amid the government’s race towards securing and sealing new COVID-19 vaccine deals while numerous criticisms have been thrown out regarding the effectiveness of the AstraZeneca.
In a media statement, Mr Frydenberg revealed, “We have gained access to the Pfizer vaccine, we have gained access to the AstraZeneca vaccine, as well as other opportunities for other vaccines and more quantities of those vaccines.”
He added “We have followed always the best medical advice. You’ve heard from epidemiologists, microbiologists and other health experts in recent days that it is important to get the vaccine out across the country.”
Meanwhile, the Therapeutic Goods Administration (TGA) is now going through its final phase of registration and approval processes as preparation for the vaccine roll-out beginning next month.
That being said, some Australian medical experts have suggested that the AstraZeneca vaccine might not be the most efficient choice as they cited it might not be enough to achieve herd immunity. There is no suggestion the vaccine is unsafe though.
Paul Kelly, Australia’s Chief Medical Officer debated concerns about the capability of the vaccine to ensure immunity was not justified at this stage of the process, thus suggested that Australians should be guided by medical research conclusions from the TGA.
As to rolling out a vaccine, Mr Kelly asserted the “choice is not whether one is better than the other.
He said “It’s which one is available to give the maximum roll-out of vaccine to save lives and to protect lives this year. The answer to that is the one we can make here.”
Panic about a second wave of coronavirus cases is “overblown,” Vice President Mike Pence wrote in June, implying the U.S. has COVID-19 under control. On the other hand, Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, warns that the U.S. is still firmly within a first wave of cases.
As media broadcast information about daily increases in the number of cases, it’s hard not to wonder which way the country is headed. Have the weeks and months of lockdown really helped? What do the trends in diagnoses and deaths mean for the course of the pandemic? Is the U.S. stuck in a first wave? Through the worst of it? Headed for a second round?
Six months into the pandemic, people are looking for ways to make sense of what’s happening. Talking about waves of disease, with the implication of predictable rises and falls, is part of that. As an epidemiologist, I know that disease waves aren’t scientifically defined. But looking to the history of previous epidemics and other countries’ current COVID-19 outbreaks can be useful.
Characterizing a wave
There’s no strict definition for what is or is not an epidemic wave or phase. A wave implies a rising number of sick individuals, a defined peak, and then a decline. The word “wave” implies a natural pattern of peaks and valleys; it hints that even during a lull, future outbreaks of disease are possible.
Historical outbreaks of infectious diseases offer some models for how the course of a disease like COVID-19 might unfold over time.
Some diseases come in somewhat predictable seasonal waves, with higher transmission rates at some times of the year than at others. Seasonal coronaviruses, like 229E or HKU1, which cause the common cold, have a high point from around December through March, according to research in the U.S.and elsewhere.
Several factors influence whether a particular disease is seasonal in nature. Some pathogens may spread less well with greater humidity. Annual epidemics, like of influenza may occur because of climate or patterns of social mixing – often driven by the school year or people staying inside more during the winter.
Waves and seasonal dynamics are also affected by levels of immunity in the human population. As more individuals become immune to a pathogen, its spread slows and eventually stops as the virus runs out of new people to infect. The U.S. is nowhere near what epidemiologists call herd immunity in the general population, however; mathematical modelers suggest at least between 43% and 60% of people would need to be immune to SARS-CoV-2 for that to be the case.
Ebb and flow, 150 years of influenza waves
Some of the current talk of coronavirus waves likely stems from comparisons with past epidemics that did show these peaks and troughs of infections.
The current COVID-19 pandemic is often compared to the 1918 H1N1 influenza pandemic, which had three distinct waves over the course of a year. The proportion of influenza patients who were severely ill or died was much higher in the last two waves compared to the first. It’s unclear whether being infected earlier on protected individuals during later waves.
More recently, the 2009 H1N1 influenza pandemic, though mild, had two distinct waves; this virus still commonly shows up in seasonal influenza outbreaks. A study of H1N1 influenza in 2009-2010 found that the second wave affected more older people, with underlying conditions.
Insight from the past suggests that discrete waves result as a disease spreads into and out of a population. Different waves can have different features, too, regarding factors like disease severity or which populations are most affected.
Currently, even with an increase in the number of cases in many parts of the U.S., there has not been a corresponding increase in the number of deaths.
The story from Iran may offer a cautionary note. From a peak of over 3,000 cases confirmed per day in early April, it declined to less than 1,000 by May, from which it has climbed to hover around 2,500 daily confirmed cases as of the end of June. The rise in the number of deaths did not occur until the second half of June. This is likely due to the time lag between when someone is infected and when they die.
Accordingly, U.S. states currently experiencing an uptick in COVID-19 confirmed cases could see a notable increase in deaths within a few weeks. The average age of those infected is getting younger, though, complicating predictions about a death toll.
The U.S. is not yet in a second wave and increasingly it looks like the country may not see one. Instead, the U.S. may sustain a constant first wave that just continues to crest. The political willpower necessary to limit transmission through robust, ongoing lockdown measures seems, unfortunately, to have been snuffed out.
But arguing about whether the U.S. is in a second wave, the first wave, or wave 1.5 ultimately doesn’t matter. Whichever it is, the commonsense actions everyone can currently take to limit the spread of infection remain the same: Staying home when possible, wearing a mask and socially distancing when out, and frequently washing hands will help speed our way beyond this pandemic, regardless of what wave we’re in.
This article is republished from The Conversation, a nonprofit news site dedicated to sharing ideas from academic experts.
Abram Wagner receives funding from the NIAID and the NSF.