Covid-19 patients usually recover within 14 days of infection, according to health experts, but data shows that some patients are fighting the virus even after 28 days, and many do not survive.
The mortality rate is higher among patients with comorbidities such as diabetes and lung disease. The use of smokeless tobacco also contributes significantly to the death of Covid-19 patients, according to a study conducted by the National Institute of Preventive and Social Medicine (NIPSOM).
The study also revealed that some patients do not recover even after a month of their Covid-19 diagnosis.
According to the study, "Assessing Risk Factors Associated with the Outcomes of the Covid-19 Patients in Bangladesh", around 61% of patients in Bangladesh succumbed within 14 days of Covid-19 diagnosis.
Of them, over 39% had lung disease and 39% had diabetes. A significant number of patients had been suffering from hypertension, cancer and chronic kidney, liver and long-term heart diseases as well.
Among the patients who died within 14 days of diagnosis, 13% were smokeless tobacco users.
Similarly, 58% of the patients died within 28 days of being infected with the virus. Among them, 40% had lung disease and 36% had diabetes.
The death rate amongst them was higher because of the increased viral load of Covid-19 in comorbid patients, said Professor Ridwanur Rahman, medicine specialist and head of the research centre at Universal Medical College.
If comorbid patients had been saved, the mortality rate from Covid-19 would have been much lower; he also added that comorbid patients with Covid-19 need to be hospitalised in order to reduce their death risk.
The study was conducted on 1,016 Covid-19 positive patients who were diagnosed at the NIPSOM Lab.
Data was collected via telephone interviews and reviews of medical reports using semi-structured questionnaires and checklists on baseline characteristics, symptoms, comorbidities, risk factors and disease outcomes.
Of the total participants in the study, nearly 70% were aged 59 or less, while just over 10% were aged 60 and above.
The study said the mortality rate in the 60 and above group within 14 days of diagnosis is about 61% and the survival rate is over 8%.
But within 28 days of diagnosis, the survival rate in the 60 and above age group is 2.8%, while the mortality rate is 56%.
The study found that the overall death rate was 2.3% on the 14th day and it was increased to 2.5% on the 28th day of the disease.
Meanwhile, patients aged 59 and above within 14 days of diagnosis had a higher survival rate of around 92%. The mortality rate in this age group is also comparatively low, at slightly over 39%. Within 28 days of diagnosis, both the survival and mortality rates in this age group are comparatively higher – at 97% and 44% respectively.
Dr Ziaul Islam, head of the NIPSOM's community medicine department and author of the study, said national protocols should be adjusted, emphasising treatment of patients within the first 14 days of diagnosis in order to reduce adverse morbidity and mortality outcomes.
To minimise the mortality rate, clinical management must be prioritised for the elderly and comorbid patients. Relevant factors must be identified through in-depth research, and specific effective measures should be taken for those who, even after 28 days, do not recover, Ziaul recommended.
The study is already accepted by the Journal "Epidemiology and Infection" of the Cambridge University for publication and sent to the World Health Organization (WHO).