Covid-19: A second wave and a vaccine of hope

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(Agung Wahyudi/IO)

IO – Eleven month since coronavirus Sars-CoV-2  was  first  announced on December 31, 2019 in Wuhan, Hubei Province of China. The global toll on 28 November 2020, reported by the World Health Organisation  (WHO)  reached  61,036,793 confirmed  cases,  with  1,433,316 deaths.

The total caseload in Indonesia up to November 28, 2020, exactly 9 months since the first case was announced on March 2, 2020, as now totaling 522,581 confirmed cases, including 16,521 deaths.

The  ratio  of  new  infections  in Indonesia per November 28, 2020

was around 193 per 100,000 inhabitants, with a fatality rate of 3.15%, according to John Hopkins University and Medicine Coronavirus Resource Center. This puts Indonesia in 18th place globally in terms of fatality rate.

The fatality rate does not seem high  when  compared  to  the  total number  of  confirmed  cases,  let alone the total population of Indonesia of over 268 million people. And it is now much lower compared to the early months after Covid-19 was detected in Indonesia, at 7.3%-8.7%. However, the fatality rate cannot be used to project the death toll because there are many other factors involved. At least this data can paint a picture on the severity of Covid-19 in Indonesia.

Is a second wave imminent?

Since early November 2020, the Covid-19 Task Force has warned about  the  possibility  of  a  second wave.  Several  countries  in  the northern hemisphere, such as those in Europe and America, are entering the winter months. Experts have long  warned  of  the  link  between long winters and increased Covid-19 and influenza cases.

Currently, several countries in Europe and America are suffering a second wave of Covid-19, which eventually forced them to impose strict restrictions on domestic and international travel. Schools, shopping places, offices and entertainment venues have been told to close again, after previously being allowed to open following a declining trend in daily cases.

The  lesson  that  we  can  learn from  countries  that  have  passed the  peak  of  the  first  wave  is  that effective implementation of health protocols and restricting human ineraction can slow the pandemic, although it demands hefty financial support from the government to maintain social and economic stability.

Australia can serve as an example. The implementation of strict state-wide  lockdown  for  an  extended period, coupled with strict observance  of  health  protocols, ranging from mask wearing, curfew, school closure, travel restrictions, and strong police presence in Melbourne for four months has succeeded in reducing new cases to close to zero.

Indonesia  is  predicted  to  experience its own second wave in the next few months, given some factors that many experts believe will see the health protocols being violated and relaxation on human activity  due  to  the  long  holiday during  the  Christmas  and  New Year, as well as holidays to compensate for Eid al-Fitr leave. In addition, the government’s decision

to allow campaigns and nationwide” “simultaneous regional elections has many people very worried.

But is it true that Indonesia has seen a downward trend in new cases and is currently facing the threat of a second wave like other countries? Or is the country still in the first wave and the peak is yet to be reached (see figure 1)?

The  term  “second  wave”  widely used today actually originated during  the  Spanish  flu  pandemic in 1918-1920. The deadly virus first appeared in August 1918 and quickly spread and infected nearly 500 million people around the globe and  killed  around  20-50  million people.  However,  it  was  a  shame that the data on the virulent characteristics of the virus and the exact number of deaths was difficult to be ascertained due to political issues and military involvement in trying to cover up the case at that time. Virus samples that can be used for further research were sorely lacking, hence there were many mysteries as to whether the pandemic was caused by a new virus or one of the influenza virus strains.

The term “wave” is used to refer to the pattern of the pandemic between 1889-1992 which underwent several different phases during the period. Past experience shows that the transmission rate of influenza can be reduced during school holidays and summer break (in 2009), although  it  will  start  to  increase again during winter.

There is a similarity in the pattern of the pandemics in 1918 and 2009 in that they began at the start of spring and decrease during the summer months. So it can be concluded that the “wave” is very much influenced by seasonal change in human  activity.  However,  this  is not always consistent in the eight epidemics and pandemics that have happened in the past.

The wave, as can be seen from the rhythmic epidemiological curve, indicates  that  the  viruses  do  not have the ability to infect the entire population simultaneously, so the curve of infections will fluctuate, as in the shape of waves. It is also possible that some of the second waves were caused by other microorganisms.

Looking  back  at  the  history  of several deadly epidemics and pandemics in the past, from 165-180 AD  to  the  present,  we  can  learn some behavioral adaptation and effective response that can be applied in the ongoing Covid-19 pandemic. This data is also used by scientists to guide various studies on pathogenesis (the process by which virus infection leads to disease), charting the  course  of  the  pandemic,  and find effective therapies or vaccines to overcome them.

Learning from history is not only useful for researchers, academics, and  policy  makers,  but  also  all segments of a society, so that they are equipped with the knowledge to debunk all the wild conspiracy theories and hoaxes regarding the Covid-19 pandemic. (see Figure 1).

In all references, even with regard  to  the  deadly  nature  of  the Spanish flu, there was never a clear definition of the waves or the peak of the waves. The wave can only be seen from the epidemiological curve as shown. A wave indicates a rising number of cases, followed by a peak, then a fall. If it goes up again, that indicates the next wave is happening. So, it can be concluded that the term “wave” describes a natural pattern of peaks and valleys during a pandemic.

Some  pandemics  in  the  past showed predictable patterns, in line with seasonal changes. For example, the infection rate of influenza viruses and seasonal coronaviruses will be higher between December and March during the winter months  and  will  recede  in  early spring.

The Spanish flu pandemic happened in three waves, with different levels of severity and death rates in each. The second wave is the most lethal phase, with a very high mortality rate. Experts estimate this is caused by viral mutation. The death rate decreases in the third wave, presumably because the number of people who were not infected was low and the virus has spread extensively enough for the population to form a herd immunity (a condition when almost all people in the population or group have acquired natural immunity after being infected). Based  on  the  chart  above  and the wave criteria according to experts, it seems too early to say that Indonesia is already entering the second  wave.  America  showed  a similar trend in June as what Indonesia’s chart looks like now and health experts in the country at the time disagreed that America had entered a second wave.

Immunity and Covid-19 vaccine

According to epidemiology, humans  in  their  lifetime  can  never be separated from interaction with the environment and exposure to pathogens (disease-causing agents such as viruses, bacteria, or other microorganisms). As long as the interaction between these three components is in check, a harmonious and balanced life can be achieved, and they can even benefit from one another.

The concept of “disease triangle” (interaction between a host, pathogen and the environment) was introduced 60 years ago by George McNew, a pathologist at the Boyce Thompson Institute for Plant Research who discovered that an epidemic or pandemic arises due to an imbalance of interactions between the  host,  pathogen  and  environment. These three components play a role and an intervention cannot be made to rectify the imbalance in one component only. (see Figure 2).

The current Covid-19 is a form of novel coronavirus from an animal whose genome has mutated. This will definitely affect the endeavor to find the right candidate vaccine to overcome the toxicity, virulence, and infectivity of the pathogen. Thus, vaccinating the host with the right vaccine is part of an intervention measure to protect the host.

The efforts to create the right vaccine are indeed the desired target and are part of the expected primary prevention. However, it should be noted that vaccines work to prevent people from catching infectious disease, not part of the treatment for those who

are already infected. So in the pro-” “cess of waiting for a safe and effective Covid-19 vaccine, all non-medicinal interventions, such as recommended health protocols, must be carried out in a strict manner, instead of being relaxed because of the belief that a vaccine will be found and will definitely be effective in preventing Covid-19 infection.

The WHO and many countries are currently striving to make Covid-19 available as soon as possible. Based on  WHO  data,  per  November  12, 2020, there are already 48 candidate vaccines currently in a clinical trial phase (including 11 candidates already in the final phase three). Furthermore, there are 164 candidates in a pre-clinical phase (undergoing testing at the cellular level or animal experimentation). As the writing of this article, the WHO or other countries have yet to announce when a vaccine will be ready for mass immunization.

The process of making a vaccine until it can be safely given to human population around the world is time-consuming, but in time of pandemics there is a policy that allows mass production to be accelerated while still observing the regulations and best practices in clinical trial. The following chart shows a comparison between traditional and accelerated vaccine production processes. (see Figure 3).

Conventionally, a vaccine development until it can be marketed to the general public after around 10-15 years. In contrast, the time needed to produce a vaccine during a pandemic is around 1.5-2 years. From clinical trial phase three until it is declared safe, then mass production takes about 6 months.

An effective vaccine is the one that can induce plasma cells in the host’s body so that it can produce antibodies that are specific to the Covid-19 antigen and induce long-lasting memory T and B cells in the host’s body so that they can remember and react rapidly if the host is exposed to the virus again. These two cellular components—the T cells (thymus cells) and B cells (bone marrow or bursa-derived cells)—play a major role in fighting infection.

Various types of candidate vaccines have been researched since the beginning of this pandemic, starting from vaccines created by inserting a killed version of the virus, recombinant virus vectors (such as adenovirus or poxvirus with proteins from coronavirus), vaccines that include subunits (parts) of the virus, and attenuated vaccine (inserting weakened viruses certain of whose genetic codes have been removed).

Judging  from  the  basic  ingredients to create a vaccine, the host conditions should be of particular concern because they will affect the efficacy of the vaccine or even endanger the host itself. The characteristic of Covid-19 infection will activate various mechanisms to “escape” the host immune system.

The mechanisms that occur can be in the form of efforts to weaken the antigen recognition of the virus, decreased number and function of immune cells, inhibition of the formation of the host’s humoral immune response, decreased ability of the cellular immune response to Covid-19, and impaired memory cells in the body. In addition, other diseases can cause immune deficiency, such as advanced age (changes in the characteristics of cellular and humoral immune cells, immunosenescence, malnutrition, protein deficiency, calories, and minerals).

Another thing that should be heeded is the possibility of contamination with other viruses, even though the factory has announced it specialises in the production of Covid-19 vaccine. Past example showed a polio vaccine in America between 1955-1963 was contaminated with the simian 40 virus (SV40). Another example is the recent rotavirus vaccine contaminated by the swine coronavirus. Efforts to check for sterility of the vaccine can take a long time.

Apart from these factors, another issue that warrants caution is related to certain antibodies that are formed “as a result of immunization which can actually cause more severe disease (called AdE, antibody dependent enhancement). These antibodies, when exposed to the virus again, will actually help the virus enter the cells and cause infection. Examples include influenza, dengue, Zika, and other viruses. Several animal experiments have shown that although capable of producing effective antibodies, several types of anti-SARS and anti-MERS vaccines can also cause more severe forms of the disease.

The Indonesian public should be careful in evaluating a vaccine. There is no need to rush things, wait until it is confirmed safe and effective. In the meantime, until a vaccine is widely available, health protocols should not be relaxed because doing so will lead to resurgence and this will render a vaccine even more ineffective.

In short, the government should set clear policy on vaccination while the public continues to wear masks, wash hands and practice social distance.”(Chyntia Olivia Maurine Jasir- wan)

Chyntia Olivia Maurine Jasir- wan is an internist and gastroenterology and hepatology consultant. She completed her PhD in clinical virology and post-doctoral study at Kobe University, Japan. She is currently pursuing a Master’s Degree in hospital administration at the Indonesia’s Faculty of ealth Science.