This confirms that many cases are going unreported due to hampered COVID-19 testing in the country in this chaos (Rocha, et al., 2021). Consequently, Covid-19 has become one of the major health concerns in Bangladesh with the highest number of confirmed cases recorded in July 2021 (WHO, 2021).
SARS-CoV-2 structure
Further examination of the viral genome showed that this species of coronavirus was 96.2% identical to a bat coronavirus. From genome sequencing, it was found that SARS-CoV-2 was 96.2% identical to a bat CoV RaTG13 and 79.5% identical to SARS-CoV.
Replication of coronavirus
13 The coronavirus particles are organized with long RNA polymers tightly packed into the center of the particle and surrounded by a protective capsid. The corona core particle is further surrounded by an outer membrane envelope made of lipids (fats) with proteins inserted.
Transmission
Antibody response against COVID-19
In general, antibodies to SARS-CoV-2 are not detected in the very early stages of infection. Anti-SARS-CoV-2 specific IgG antibodies were detected as early as day 7 of illness onset and peaked at approximately 25 days from illness onset, and levels were still high 4 weeks later.
Cytokine response against COVID-19
In the early stages of infection, no significant difference was observed in serum IgG levels between mild and severe cases, but after 15 days of disease onset, both IgM and IgG levels were robustly increased in cases of severe disease. Both pro-inflammatory and anti-inflammatory cytokines are induced in the serum of patients with CS.
Cellular response against COVID-19
Therefore, in patients with COVID-19, along with antiviral therapy, anti-inflammatory therapies that reduce cytokine responses are needed. Due to the initial local respiratory SARS-CoV-2 infection, innate immune cells circulating in the blood, including natural killer cells, monocytes, neutrophils, and dendritic cells are altered.
Laboratory diagnosis
It detects antibodies that are produced by the immune system in response to a threat, such as a specific virus. Serological testing of COVID-19 does not target the virus itself, but antibodies such as immunoglobulin M (IgM) and immunoglobulin G (IgG) induced after viral infection.
Disease burden
20 Currently, the routine clinical diagnosis of Covid-19 is mainly based on epidemiological history, clinical manifestations, and is confirmed by various laboratory methods such as CT scan, nucleic acid amplification test (NAAT) and serological techniques.
Prevention
Vaccination
Covishield is the vaccine currently approved for use in Bangladesh to prevent the spread of COVID-19. However, data are available for administration of the second dose up to 12 weeks after the first dose from studies abroad. After vaccination with ChAdOx1 nCov-19 Corona Virus Vaccine in participants who were seronegative at baseline, seroconversion (as measured by a ≥ 4-fold increase from baseline in S-binding antibodies) was detected in ≥ 98% of participants 28 days after the first dose and >99% 28 days after the second dose.
It provides immunogenicity for at least 119 days after the first vaccination and is 95% effective in preventing the SARS-COV-2 infection. Systemic adverse reactions were reported more frequently after the second dose than after the first dose and appeared to be more frequent and severe in persons aged 18-55 years than in persons over 55 years of age. Severe reactions were reported more frequently after the second dose than after the first dose and were less common in older than younger participants.
Moderna Vaccine
This vaccine is also administered intramuscularly in the deltoid muscle with an interval of 28 days between vaccinations. Taking this vaccine may result in mild side effects after the first or second dose, including pain, redness or swelling at the vaccination site, fever, fatigue, headache, muscle pain, nausea, vomiting, itching, chills, and joint pain. and can also rarely cause anaphylactic shock. Vaccine, 2021) Side effects are relatively more common with this vaccine than with the Pfizer vaccine.
Janssen (Johnson & Johnson) Vaccine
This vaccine uses existing technology that includes adenovirus (Type 26) which commonly causes respiratory infections. Some of the yeast proteins produced by the cell form spikes that migrate to its surface and eject their tips. These prominent spikes and fragments of yeast proteins can then be recognized by the immune system.
By raising this alarm, this vaccine causes the immune system to react more strongly to the nail proteins. When a vaccinated cell dies, the debris contains spike proteins and protein fragments that can then be taken up by a type of immune cell called an antigen. presenting cell. Any person with a severe allergic reaction to any component of the vaccine formulation should avoid this vaccine. Livingston, et al., 2021) However, recent reports of a few cases of blood clots between six to thirteen days after vaccination have prompted authorities in some countries to stop administering this vaccine.
Mixing of different vaccines
In the studies of this vaccine, no one developed a serious allergic reaction, and side effects of the vaccine were similar to those of other vaccines. In clinical trials, side effects were common within 7 days of being vaccinated, but were mostly mild to moderate. Side effects were more common in people 18-59 years old compared to people 60 years and older.
Parkins, 2021) Therefore, some countries have considered mixing doses to make sure that each person receives two doses of vaccine. In fact, some countries in Europe such as Germany and France have recommended the use of an mRNA vaccine as the follow-up dose in people under 55 and 60 years old, respectively, to strengthen their immune system. In the UK, concerns about complications after the Astra Zeneca shot have already discouraged many from taking a follow-up shot.
COVID vaccine for children
Since these vaccines must be given twice with an interval of at least four weeks, a lack of vaccines to provide second doses was observed. Other countries such as Norway and Great Britain are awaiting the results of clinical trials to make this decision. If the mixture of vaccines is proven to be safe, then such individuals can receive an alternative vaccine for their second dose, thereby avoiding adverse vaccine effects.
However, one of the disadvantages of this extremely strong immune system in children is that it increases the chances of negative effects after vaccinations.
Thrombotic complications of COVID-19 vaccination
In the United States, adverse effects of vaccination can be reported by healthcare workers in the Vaccine Adverse Event Reporting System (VAERS) via the Center for Disease Control (CDC). Incidence of adverse effects after vaccination with COVID-19 varied among different health care workers in different settings. Similarly, in the Czech Republic, symptoms such as pain at the injection site, fatigue, headache, muscle aches and chills were the most commonly reported adverse effects.
Here, the prevalence of side effects was comparatively less than that reported for mRNA-based vaccines. A study of healthcare workers in India reported 57% non-severe AEFI after the first dose and 14.1% after the second dose (Kamal, et al., 2021). In another study from Nepal, about 80.9% complained of side effects after immunization, with pain at the injection site being the most common.
Acceptability of COVID-19 vaccination among healthcare workers
In Germany, the mRNA-based Pfizer-BioNTech and Moderna vaccines were given to healthcare workers, where more than 88% of healthcare workers complained of at least one adverse effect (Klugar, et al., 2021). 33 previous adverse effects of other vaccines and know little about the long-term adverse effects of the newly developed COVID-19 vaccine.
Current situation of vaccination
Materials and Methods
- Description of the study area
- Study Design
- Case definition
- Vaccine composition
- Criteria for getting into vaccination program
- Study period
- Questionnaire used
- Data collection
The interviewee's demographic characteristics, social history, allergic history, history of co-morbidities were included in the first part of the questionnaire. In the second part, history of contracting COVID-19 before vaccination, vaccination history and adverse effects of vaccination were recorded. For offline forms, study subjects were randomly selected and approached with the questionnaire by the principal investigator.
For online data collection, the questionnaire was sent out as google forms to various platforms on Facebook. Univariate association between pre-vaccination COVID-19 cases and various factors was performed using chi-square test, and p-value <0.05 was considered significant. Bar graphs were also made to show the number of sick days after vaccination; and the interval in days between vaccination and diagnosis of COVID-19.
Results
39 Table 1: Univariate association with the factor and enrolled population becoming positive for COVID-19 before vaccination. A univariate analysis was conducted between the different factors among the respondents participating in the survey and their association with becoming positive for COVID-19 before vaccination. Nearly half of patients (n=185) were taking medications to address the adverse effects of the COVID-19 vaccine and 23 patients developed COVID-19 infection despite immunization against the disease.
The frequency of sick respondents decreased as the number of days after vaccination increased. In the bar chart above, we see the number of days that passed between the respondent's vaccination and the diagnosis of COVID-19. Although the number of diagnosed cases was not significantly related to the number of days after vaccination, a peak in incidences was observed on the 8th day after vaccination.
Discussion
Along with this, a significant reduction in the consumption of electricity has also been observed in several cities (Ghosh, et al., 2020). Before that, two million doses were donated to Bangladesh by the same country (Chatterjee, et al., 2021). Healthcare workers of a younger age (19-30 years) and women were more likely to develop adverse events after vaccination (Inbaraj, et al., 2021).
Other complications such as autoimmune hepatitis (AIH) after vaccination (Rela, et al., 2021) and development of blood clots (Grant, 2021) are rare cases of vaccination-induced adverse events that have been reported. At the same time, increasing public attention is focused on these rare risks of vaccination (Siddiqui, et al., 2013). This may be due to the decrease in reactogenicity among patients with diabetes mellitus (Remlabeevi, et al., 2021).
Conclusion
Limitations
Recommendations
