Covid Surge: States of Crisis

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Adapted from: India Legal, April 10, 2021

Cases of coronaviruses are rising swiftly in the ongoing second wave of Covid-19 with over one lakh new cases now being recorded in the country every day. At the time of writing this (7.4.2021), India added 1,15,736 new cases in the last 24 hours to its total tally of active cases, which is 8,43,473. At this rate of resurgence of cases, India may possibly become the country with the highest number of cases surpassing the United States, currently the worst-hit country in terms of the number of cases.

During the first wave of the pandemic, it took 108 days for the cases to rise from 8,000 on June 2 last year to reach the figure of 97,000 on September 17. But, in the second wave, the numbers have increased from 8,000 on February 2, 2021 to cross the one lakh mark on April 5 in just 63 days.

In contrast to the first wave, eight states, in particular, are contributing 80.70 percent of the total new cases reported in the country in the second wave, according to Health ministry data and are the new hotspots for the infection. These eight states include Maha­rashtra, Chhattisgarh, Karnataka, Uttar Pradesh, Delhi, Madhya Pradesh, Tamil Nadu and Kerala. Among these, Delhi is experiencing the fourth wave of the pandemic; Madhya Pradesh the third wave, while the remaining six states are in the midst of the second wave.

Hotspots are areas with a high burden of disease or high transmission efficiency. In hotspots, cases will occur in spurts and form several clusters. Three different types of infection hotspots have been defined: Transmission hotspots i.e. areas with high transmission efficiency and where the reproductive number (R0) is high; emergence hotspots i.e. areas with a high frequency of disease emergence and burden hotspots i.e. areas with high incidence of disease. Interplay of several factors such as overcrowding, poverty, hygiene, geographic clusters results in transmission hotspots. Superspreaders and superspreading events also influence the spread of the infection. The SARS-CoV-2 virus mainly spreads through respiratory droplets produced during coughing, sneezing, singing, and even talking loudly. A superspreader is a person who has a high viral load as compared to the average person carrying the infection and hence spreads the infection to a disproportionately large number of people because of high viral shedding, while a superspreader event is a big gathering of people where a single infected person can cause an explosion of infection among people present at the event and who do not take any precautions like face masking, physical distancing. Crowded indoor events such as weddings, funerals, large family gatherings, conferences, offices, schools, religious gatherings, especially if they are ill-ventilated, have the potential to become superspreading events as people are in close contact with each other. Evidence has shown that that 80 percent of new cases via local transmission are caused by 20 percent of already infected persons similar to the Pareto principle, also known as the 80/20 rule, which states that “for many outcomes, roughly 80 percent of consequences come from 20 percent of the causes (the “vital few”).

A study published last year in September in CDC’s Morbidity and Mortality Weekly Report (MMWR) has shown that eating out at restaurants increases the risk of infection. This is because it is not possible to wear a mask while eating. Also, people may be sitting close to each other. Similarly, bars, gyms, clubs are also high risk areas. This is because when a person coughs, the droplets containing the virus may spread as far as 19 feet, while a sneeze can cause droplets to travel up to 26 feet. While some fall down and contaminate the surfaces, some remain suspended in the air as aerosols for many hours. Depending on the ventilation and the air flow pattern in the room, the aerosols can spread in the entire room. About 10 percent of droplets released during a cough can remain in the air after travelling for a distance of six feet.

Population density also has a direct association with the number of cases. Population density is not just the number of persons per square kilometre calculated for a city or a country. It also illustrates the household density (density of households within a particular geographical area). The probability of the spread of infection is far greater in densely populated areas, more so among persons living in crowded houses, where they are in close contact with one another. Physical distancing is difficult or practically impossible to maintain in such housing conditions. Socioeconomic status plays a significant role in household crowding.

Furthermore, the number of people travelling in public transport and trains in India is huge. Waiting in queues is also risky, more so when people do not comply with physical distancing measures in place.

The state of Maharashtra alone has added almost 60,000 new cases to the country’s cumulative tally even in the ongoing second wave of the infection. Chhattisgarh comes next with 9,921 cases followed by Karnataka with 6,150 new cases. The rising positivity rate is a matter of concern. When it is more than 10 percent, this means community spread. The daily positivity rate is 8.40 percent. In Maharashtra, it is 15 percent, whereas in Delhi it is 5.5 percent. According to the WHO, any outbreak is said to be under control, if the positivity rate is 5 percent or less.

Although there is no nationwide lockdown, partial lockdowns are back in many states in an effort to break the chain of transmission.

However, prior to this, there were hardly any restrictions on the movement of people, both within and outside the states. There were gatherings coupled with total lack of adherence to Covid-19 appropriate behaviour with no masking and physical distancing. People had started travelling in local trains in Mumbai where physical distancing is simply not possible. Testing frequency had dramatically declined. Some complacency had set in as the numbers had started to decline by early February. The result was a resurgence of cases.

There is also a new strain of the virus circulating, which is more infectious and therefore is spreading rapidly. Since most cases in Maharashtra are asymptomatic, people do not follow isolation guidelines. Apparently people do not fear Covid-19 as much now as they did when it was first identified and was a mysterious disease. In some districts, institutional quarantine is being done even for asymptomatic cases otherwise they may become source of infection. This endangers the overwhelming healthcare services and resources.

Covid-19 is a highly contagious disease caused by the SARS-CoV-2 virus. This virus is undergoing mutations as it travels from person to person. The new variants have increased transmissibility and therefore spread easily and more rapidly. Pathogen (virulence and infecting dose), host (shedding of the virus, variant), environment (population density, mass gatherings in closed spaces, poor ventilation, physical distancing), behaviour (hand hygiene, cough hy­giene, adherence to protective measures) and response (timely implementation of control measures in the affected areas) are factors that increase the possibility of a superspreading event.

Although, Covid-19 has become more manageable now, public health strategies are the best bet to control the infection. Containment zones need to be identified in hotspots and strict isolation measures implemented. Contact tracing must be increased. More and more testing needs to be done. Tests must be directed towards detecting at least three gene targets, else variants can be missed. These have to be done on a war footing. Correct, continuous use of a three-layered mask supported by physical distancing, frequent handwashing (or use of sanitiser), avoiding crowded places are as important now as they were in the first wave. Entire families are becoming infected now. Vaccination has to be aggressively pursued. Since the vaccinations so far are being administered in phases for defined population groups, a huge population is still vulnerable to the infection. So far, the number of new cases in the second wave has remained quite low in the north east states of India except Assam. But, infection may still reach these parts. As citizens of this country, we have to act responsibly. Together we can, together we will.

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

CMAAO Coronavirus Facts and Myth Buster – Whole virus is more thrombogenic than the spike part

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With input from Dr Monica Vasudev

The risk of developing cerebral venous thrombosis (CVT) from COVID-19 appears to be several times higher than that from administration of the AstraZeneca/Oxford or the Pfizer and Moderna mRNA vaccines.
A University of Oxford study has noted that from a dataset of more than 500,000 COVID-19 patients, CVT would have developed in 39 per million individuals.
CVT has been reported in about 5 per million people after a first dose of the AstraZeneca vaccine.
Among more than 480,000 people administered either the Pfizer/BioNTech or Moderna mRNA vaccines, CVT was noted in 4 per million.
Compared to the mRNA vaccines, the risk of CVT from COVID-19 was nearly 10 times higher.
In comparison with the Oxford vaccine, the risk of CVT from COVID-19 was around 8-fold higher.
A similar pattern has been observed for portal vein thrombosis (PVT), which was observed in 436.4 per million individuals who had contracted COVID-19. In comparison, the figure was 44.9 per million for the mRNA vaccine, and 1.6 per million for those administered the AstraZeneca vaccine.
Major issue – the comparison showing the higher risk after COVID-19 does not exclude the possibility that the pathogenesis is the same and some common denominator should therefore be explored.
If the mechanism is same, it can be speculated that the high occurrence in COVID-19 compared to vaccination is because the whole virus is more thrombogenic than the spike protein alone.
These studies are important but they focus on showing the minor risk of vaccination instead of trying to explain the cause of complications, making use of the similarities of the events in the two populations. [Medscape]

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

CMAAO Coronavirus Facts and Myth Buster – Vaccine Updates

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With input from Dr Monica Vasudev

1562: Moderna says its coronavirus vaccine provides strong protection up to 6 months after a second dose. The company stated that updated cases point to continued strong efficacy of more than 90% against cases of COVID-19 and more than 95% against severe cases of COVID-19, with around 6 months median follow-up following the second dose. The results are in line with a report in the New England Journal of Medicine which noted that 33 individuals who received the Moderna vaccine had a strong antibody response after 6 months. (Mint; Business Today)

1563: Denmark has stopped the rollout of Oxford-AstraZeneca vaccine completely. Officials stated that 2.4 million doses of the vaccine would be withdrawn until further notice. The Health Authority mentioned that studies had shown that there was a greater than expected frequency of blood clots after vaccine doses, affecting about one in 40,000 people. It came after two cases of thrombosis were reported in the country that were linked to vaccinations. One of them, in a 60-year-old woman, was fatal.

Close to one million people in Denmark have been vaccinated, with about 150,000 of them having received the AstraZeneca shot. The Pfizer/BioNTech and Moderna vaccines are also being used.

Adenovirus vaccines – Adenoviruses enter the cells and make use of the cells machinery to produce a piece of the virus that causes COVID-19, a spike protein. The cell identifies that the spike protein does not belong there and the immune system is triggered to fight against the presumed infection. This trains the body to protect us against COVID-19. Regulators are now evaluating of an unusual immune response to the adenovirus vaccines is the reason behind the rare but severe events of blood clotting.

It seems obvious that the cases of blood clots tied to the Johnson & Johnson vaccine were very similar to those associated with the AstraZeneca vaccine. The US halted the Johnson & Johnson vaccine rollout after six women below 50 years of age developed rare blood clots after receiving the vaccine dose. In the UK, 30 people had developed unusual blood clots and seven of them died after the AstraZeneca jab, out of 18 million vaccinated people.

Some European countries have restricted the use of adenovirus vaccines to older people, who seem to have been less affected by the blood clotting condition. After the announcement from Denmark, France stated that it considered the AstraZeneca vaccine as an essential tool and that it was important that this vaccine is used. It is a safe vaccine and it works, stated French government spokesman. France will also give the Johnson & Johnson vaccine to those aged above 55. It has received 200,000 doses. Belgium will also give the doses it has received, while Greece and Italy won’t.

The Czech Deputy Prime Minister Jan Hamacek had asked the Czech ambassador in Denmark to buy the 2.4 million AstraZeneca vaccines doses that the country would not be using anymore. He added that he would also travel to Moscow to arrange supplies of the Sputnik V vaccine, once its use is approved by the EMA.

The Gamaleya Center that has developed the Sputnik V vaccine stated that it had noted no cases of blood clots associated with its vaccine. It added that all vaccines based on adenoviruses were different and were not directly comparable. (BBC)

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA

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