Why is Covid rising again?

After the arrival of Covid in the country, at least five waves have hit so far. The gap between one to another wave always remained more than two to three months. But, after the end of the fifth and the last one, which started in June, the infection has been rising again.

Consultant of the government’s Institute of Epidemiology Disease Control and Research (IEDCR) Mushtuq Husain told to Prothom Alo, “The increase of virus has never risen in such short space of time. This can be termed as the sixth wave."

The infection of the fifth wave of Covid, which started in the second week of June, started to decline at the end of July. During the first week of August, the rate of corona detection fell to under five percent. The public health experts had hoped the arrival of new wave would take more time. And even if that would come, it would not be long standing. Experts considered mass vaccination a major safeguard. But Covid has been increasing since the end of August and is increasing at an even higher rate. According to the Covid reports of the last 24 hours, the rate of detection was 12.73 percent. During that time five people died of the virus. After eight weeks the number of deaths reached such high. In the 33rd week of pandemic, from 15 to 21 August this year, the rate of Covid detection was 28 per cent less than that of previous year. In next week, from 22 to 28 August the rate of corona detection increased to 22. In next week the rate of detection increased little more than seven percent. During 5 to 11 September, corona increased by 47 per cent. And in last week, from 12 to 18 September, corona increased by 28 per cent.

Why is the infection spreading so fast even before the impact of the prior wave diminishes? Experts talked about various reasons behind this. The first one is, during last wave, the fifth one, the infection did not spread fully. The second is, a large portion of the population did not take the second dose of corona vaccination, the third is, the ability of Omicron to dodge the resistance created by the vaccines and fourth, reluctance in all sectors about health regulations due to prolonged pandemic. 

So far Bangladesh has seen five corona waves and the last one stayed for the least time. The number of detections and deaths was also less during this period compared to those of previous waves. For example, during the fourth wave of corona, between January and February of the current year, 965 people died from the Omicron virus. And during fifth wave at June and July 160 people died in total. The fifth wave spread two types of Omicron - B.A 4 and B.A 5.

This time there is a special feature in the spread of corona. After the outbreak of Covid in the country, each wave has started with a new type. This time a new wave is being created with two types of Omicron.

International Centre for Diarrhoeal Disease Research Bangladesh (icddr,b) collected genome sequencing of 38 samples from July 23 to September 9. It was seen, in Dhaka 26 samples were BA.5 and 12 samples were BA.2 subtype. Initially the BA.5 spread the infection in highest rate. Later BA.2 also joined.

Epidemiologist Mushtuq Husain thinks that one of the reasons for the spread of infection so rapidly this time may be that the previous wave was not completed. He told Prothom Alo when an epidemic occurs, the infection continues to spread as long as there is an opportunity. If that opportunity is closed, either naturally or due to the health system, the virus waits for an opportunity to spread. Our laxity in following the rules of hygiene has contributed to the sudden spread of the virus.

Mushtuq Husain said, the risk of those who were infected through BA.5 getting infected this time is very little. But those who have not, have that fear. Rapid health measures may have played a role in the rapid end of infections last time. At that stage the infection could not spread completely and now it is spreading. But this time the infection does not seem to be very high.

Vaccination is considered a protective shield against Covid. 77 per cent of the total population of the country has received the first dose of vaccination. 71 percent of people received the second dose of vaccine. And 26 percent of people took booster dose. A total of about 30 million doses of vaccine have been administered so far. About 3.3 million people have not taken the first dose of corona vaccine in the country, and about 9.4 million people have not taken the second dose. The researchers said that if the second dose is not taken after the first dose, it will not be effective.

Public hygienist and former director, disease control of the health department, Be-Nazir Ahmed told Prothom Alo, "According to the government, 70 per cent of people have not taken the booster dose. Those who took two doses had reduced immunity. People among them are getting infected. But their situation is not serious. If 70% of people had taken the booster, the infection would have been less."

The Omicron subtypes of BA.4 and BA.5 may dodge the antibody created in the body of the corona-affected and the ones who have taken vaccine, according to a study of Beth Israel Deaconess Medical Centre of Harvard Medical School in the United States. The report was published in the New England Journal of Medicine last June. However, it is said that the corona vaccine can still play a significant role in protecting against serious conditions.

Professor Be-Nazir said, “Many researches have shown that the subtypes of Omicron have the ability of dodging body’s antibodies. And there are different types of immunity depending on vaccines. I can't show the results of any research, but from the observation, it can be said that even in the vaccine producing countries, mass vaccination and strict lockdown have not been successful. That matter should also be taken into consideration."

World Health Organisation (WHO) said recently, the world is in best state after the spread of corona although the infection is not stopped yet. But this pandemic persists. A huge number of corona patients are being detected in Asian countries like Japan and South Korea. Many areas of China are still under lockdown. It has been almost three years in this situation, in many places people do not want to follow the hygiene rules prescribed to prevent corona.

Former Chief Scientific Officer of IEDCR ASM Alamgir considers this to be a global trend. He said, the whole world is trying to show normalcy by force. And while trying to show normalcy, the infection is increasing. But in Bangladesh we are in a bit of an advantageous position, because vaccination is relatively good here though eight million people did not take the second dose. One cannot expect the effectiveness of the vaccine if the second dose is not taken. Public hygienists say, extreme laxity is being observed in maintaining the health code in Bangladesh. Public meetings are taking place and people are not following the health guidelines in public. This is playing a role in increasing the spread of Covid.

The National Technical Advisory Committee regarding Covid-19 last Saturday made five recommendations. These include, wearing masks properly and ensuring washing hands or using sanitisers and encouraging people to follow health guidelines. In addition, it is recommended to encourage those who have not received the first, second and booster doses of the corona vaccine to take the vaccine. The committee recommends refraining from holding meetings in confined spaces and to conduct official meetings virtually as much as possible. Masks are also recommended for essential social events or gatherings.    

The number of Covid cases is increasing in the country but the number of deaths is still low. Public health experts think there is almost no guarantee that the number of infections and deaths will not increase in next one to two weeks.  So, alongside vaccines, the health guidelines must be followed.

ASM Alamgir said, “Vaccination is not the only safeguard. But following health guidelines is a proven way. This requires campaigns to raise people's awareness.”