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| ORIGINAL ARTICLE |
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| Year : 2022 | Volume
: 24
| Issue : 1 | Page : 30-36 |
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Clinicoepidemiological profile of COVID-19-positive migrant population and their outcomes: A multicentric, retrospective study from Northeast India
Joydeep Ghosh1, Amit Kumar Das2, Manasa Shettisara Janney3
1 Department of Surgery, Military Hospital, Dimapur, Nagaland, India
2 Department of Pathology and Laboratory Medicine, INHS Asvini, Mumbai, Maharashtra, India
3 Department of Dermatology, Military Hospital, Dimapur, Nagaland, India
| Date of Submission | 16-Mar-2021 |
| Date of Decision | 05-Jun-2021 |
| Date of Acceptance | 09-Jun-2021 |
| Date of Web Publication | 21-Jan-2022 |
Correspondence Address:
(Dr) Manasa Shettisara Janney
Medical Officer, Department of Dermatology, Military Hospital, Dimapur - 797 112, Nagaland
India
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/jmms.jmms_42_21
Introduction: Emergence of a novel coronavirus disease (COVID 19) and its subsequent spread to India lead to declaration of lockdown by the government in various phases to reduce the transmission of COVID 19. Northeastern India being relatively remote had its first case relatively late. Later, with incoming migrant population, there was a surge in cases. This study aims to determine the clinicoepidemiological characteristics and outcomes in COVID 19 positive migrant population treated at multiple centers in Northeast India. Methods: This is a retrospective, cross-sectional,multicentric study. Data were collected from case sheets of 198 COVID-19 positive patients treated at designated COVID-19 hospitals in Northeast India. Results: Independent t-test and Fisher's exact test were used. P<0.05 was considered statistically significant. Majority of the study population were between 31 and 50 years (62.1%) with overall male preponderance (94.9%). Nearly one third (31.8%) of the study population gave a history of contact. Fever was seen 92.4% of patients. Majority (97.0%) of the study population had mild to moderate disease and only 3.0% were severely diseased/critically ill. 30%, 7%, and 3% of the study population received oxygen support, noninvasive ventilation, and ventilator support, respectively. Only 1.5% of the study population had complications of acute respiratory distress syndrome, shock, and sepsis, and the mortality rate was 1.1%. The average duration of hospitalization was 14.17 ± 5.48 days, and the average time taken to become COVID negative by reverse transcription polymerase chain reaction was 37.93 ± 7.54 days. Conclusion: A large number of COVID-positive patients had mild-to-moderate course of disease. Fever was the most common symptom. Around one-third of patients required respiratory support. Rate of complications and mortality were low in the study population. Presence of comorbidities, "O" blood group, abnormal X ray findings, elevated levels of C reactive protein, D dimer, and erythrocyte sedimentation rate had a significant positive association with severity. Keywords: COVID-19, migrants, Northeast India
How to cite this article:
Ghosh J, Das AK, Janney MS. Clinicoepidemiological profile of COVID-19-positive migrant population and their outcomes: A multicentric, retrospective study from Northeast India. J Mar Med Soc 2022;24:30-6 |
How to cite this URL:
Ghosh J, Das AK, Janney MS. Clinicoepidemiological profile of COVID-19-positive migrant population and their outcomes: A multicentric, retrospective study from Northeast India. J Mar Med Soc [serial online] 2022 [cited 2023 Apr 1];24:30-6. Available from: https://www.marinemedicalsociety.in/text.asp?2022/24/1/30/336193 |
| Introduction | |  |
COVID-19 is a global pandemic caused by a novel coronavirus (SARS-CoV-2). It was first detected in Wuhan, China, in December 2019 and later spread to every corner of the globe.[1] India's first case of COVID-19 was reported in January 2020.[2] The Government of India declared a nationwide lockdown to control the transmission of the virus. Due to the effective enforcement of lockdown and continued restriction of movement in Northeast India, the number of COVID cases was lower than the national average initially. With the relaxation of lockdown, Northeast India saw a surge in cases.[3]
COVID-19 has a wide spectrum of presentation. Data from various countries have demonstrated a global variation in clinical characteristics.[4] There is a paucity of large-scale studies in published literature from the Indian subcontinent. The objective of this study is to determine the clinicoepidemiological characteristics and outcomes in COVID-19-positive migrant population treated at multiple centers in Northeast India
| Subjects and Methods | | |
This was a retrospective, cross-sectional, multicentric study carried out among 198 COVID-19-positive migrant patients treated at various COVID-19 hospitals in the remote areas of Nagaland, Manipur, Assam, Arunachal Pradesh, Tripura, and Mizoram. The study population included the migrants returning to work following relaxation of lockdown, whose nasopharyngeal swabs were screened and tested positive with reverse transcription polymerase chain reaction (RT-PCR) as per local policies in the Nearest ICMR-certified laboratory. After obtaining clearance from the institutional ethical committee, the data were collected by retrieving information from the documents dated from 1 June to 30 September, 2020, at the above-mentioned centers.
The data were collected from the case sheets which included the details on various clinicoepidemiological variables such as age, sex, blood group, comorbidities, Bacille Calmette–Guérin (BCG) vaccination status, clinical symptoms, severity, respiratory rate, oxygen saturation, intensive care unit (ICU) admission, respiratory support, complications, lab parameters, chest X-ray findings, duration of hospital stay, and hospital deaths. As the lab parameters and chest X-ray findings are dynamic and vary as the disease progresses, investigations conducted at admission were considered in those patients who were stable throughout hospitalization and repeat investigations conducted on clinical deterioration were considered in those patients whose disease progressed during hospitalization. Clinical severity was described as mild/moderate/severe or critical based on clinical signs, lab parameters, and radiological findings as laid down in the clinical management protocol: COVID-19 issued by the Government of India[5] and mentioned in [Table 1]. | Table 1: Clinical category classification (adapted from clinical management protocol: coronavirus disease 2019 of GoI issued in June 2020)
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The data were entered into MS Excel sheet. Quantitative discrete variables and qualitative variables were expressed in terms of proportions and continuous variables were expressed in means and standard deviation. The continuous variables were compared between the severities (mild and moderate vs. severe) using independent t-test, and the difference in proportions and association with the severities were assessed using Fisher's exact test. The analysis was carried out in SPSS version 20.0 and P < 0.05 (IBM Corp. Released 2011. IBM SPSS Statistics for Windows, Version 20.0. Armonk, NY: IBM Corp.) was considered statistically significant.
| Results | | |
The mean age of patients was 35.4 ± 8.67 years and it ranged between 19 years to 65 years. Majority of patients were in the age group of 31-50 years (62.1%). Males (94.9%) outnumbered females (5.1%). Only 10.1% of patients had preexisting comorbidities, with hypertension being the most common (9/20, 45.0%). Nearly 80.0% of patients gave a history of BCG vaccination [Table 2].
Around one-third (31.8%) of patients gave a history of contact with COVID-19 patients. The most commonly affected blood groups were blood Group A (38.8%), followed by B (24.2%) and O (23.9%), and the least affected was blood group AB accounting to 13.1%. Majority of patients (98.9%) were symptomatic and reported various symptoms, among which fever was the most common (92.4%), followed by myalgia (50.0%). At admission, 98.4% and 1.5% of patients had mild and moderate disease, respectively. Among the patients with mild disease at admission, 28.2% (55/195) of patients progressed to moderate disease, with recorded SPO2 during hospitalization being 90-93% and 2.1% (2/195) progressed to severe disease with recorded SPO2 < 90%. Progression to severe or critical disease was seen in all patients with moderate disease. Based on clinical features, radiological findings, and SPO2 levels during hospitalization, 3.0% of the study patients were found to have severe or critical illness and the remaining 97.0% had mild-to-moderate disease. About 30% (61/198) of patients were managed with oxygen inhalation, 7% (14/198) with noninvasive ventilation, and 3% (6/198) required invasive ventilation. Only 1.5% of patients had complications of acute respiratory distress syndrome, shock, and sepsis, and the mortality rate was 1.1% [Table 3] and [Figure 1]. The observed laboratory parameters and radiological findings are mentioned in [Table 4]. | Table 3: Clinicoepidemiological profile and outcome of the study subjects (n=198)
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The sociodemographic and clinicoepidemiological variables, namely, age and gender, history of tuberculosis in the past, BCG immunization status, and history of contact with COVID-positive patients, were not found to be significantly associated with the severity of illness (P > 0.05). However, the mean age was significantly higher among those with severe disease and critical illness (43.60 ± 6.12 years) compared to those with mild and moderate disease (35.19 ± 8.64 years) (95% confidence interval [CI]: −15.16 to − 1.13; P < 0.05). The proportion of severe and critical illness was significantly higher among those with comorbidities (27.3% vs. 1.6%) and “O” blood group (10.6% vs. 0.7%) compared to those with no comorbidities and other blood groups (P < 0.05). Among the laboratory and X-ray parameters, the proportions of severe and critically ill patients were significantly higher among those with elevated levels of C-reactive protein (CRP) (17.6% vs. 0.0%), D-dimer (100.0% vs. 2.0%), erythrocyte sedimentation rate (ESR) (100.0% vs. 1.0%), and abnormal X-ray changes (40.0% vs. 0.0%) compared to those with normal laboratory and X-ray parameters (P < 0.05) [Table 5]. | Table 5: Association of various sociodemographic, clinicoepidemiological, X-ray, and important laboratory parameters with severity of illness¥
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The average duration of hospitalization was 14.17 ± 5.48 days ranging from 7 to 39 days. The average time taken to become COVID negative by reverse transcription polymerase chain reaction (RT-PCR) was 37.93 ± 7.54 days (n = 196) and it ranged from a minimum of 21 days to a maximum of 72 days. The duration of hospitalization was also significantly higher among those with severe disease and critical illness (22.33 ± 7.29 days) compared to those with mild and moderate disease (13.76 ± 5.23 days) (95% CI:-12.89-4.25; P < 0.05). However, the duration to become COVID negative by RT-PCR did not vary significantly with the severity (severe disease and critical illness vs. mild and moderate disease: 43.75 ± 3.50 days vs. 37.82 ± 7.56 days; 95% CI: −13.42-1.56; P > 0.05).
| Discussion | | |
COVID-19 pandemic has posed a huge threat to global public health. Among the various sections of the community, migrants are at increased risk of contracting COVID-19 as they live in overcrowded conditions without the means to follow basic public health measures.[6] The present study was conducted to understand the clinicoepidemiological profile and outcomes among COVID-19-infected migrant population.
Sociodemographic profile
In this study, the mean age of the study population was 35.4 ± 8.67 years with majority in the age group of 31-50 years and male predominance. Only 10.1% of the study population had preexisting comorbidities, with hypertension being the most common. These findings are comparable to the study findings of Bhandari et al., with study participants in the age group of 38.8 ± 18.9 years with a male preponderance.[7] Tambe et al. noted a mean age of 45.8 ± 17.3 years, with majority of the study patients in the age group of 31-60 years with male dominance. 47.2% of the study population reported one or the other comorbidity, hypertension being the most common one. The mean age and occurrence of comorbidity were higher compared to our study; the difference may be due to different study settings and study population.[8] Dickson et al. also found hypertension as one of the common comorbidities among the COVID-19 cases in India.[9]
Clinicoepidemiological factors and outcomes
Nearly one-third (31.8%) of patients gave a history of contact with COVID-19 patients, which is comparable to the study findings of Tambe et al., with 29.1% contact history.[8] The most commonly affected blood group was A blood group, which is similar to the findings of Zhao et al.[10]
Fever was the most common symptom in the current study, followed by myalgia and anosmia. Various other symptoms included cold, cough with or without sputum, fatigue, dyspnea, myalgia, headache, anosmia, sore throat, chest pain, conjunctival congestion, skin rashes, pain abdomen, loose stools, pain in the eyes, dizziness, and anorexia. Study findings are comparable to Firdaus et al., who noted that fever followed by cough were the most common symptoms, others included pain abdomen, nausea, vomiting, diarrhea, sore throat, malaise, fatigue, shortness of breath, rhinitis, cold, loss of smell and taste, anxiety, chest pain and headache.[11]
The WHO China Joint Mission on coronavirus disease reported that 80% of the individuals with COVID-19 infection showed mild-to-moderate disease and 13.8% had severe disease.[12] In this study, we noted that majority (97.0%) had mild-to-moderate disease and only 3.0% of the study patients were severely diseased or critically ill similar to the findings of Mohan et al., who noted that 2.8% had severe disease, whereas the remaining 97.2% had mild-to-moderate disease.[13]
Progression to severe disease among mild and moderate cases was noted in 1.6% and 33.3%, respectively. In studies by Mohan et al., Guan et al., and Huang et al., overall progression to severe disease was noted among 3.5%, 15.74%, and 32%, respectively.[13],[14],[15]
In this study, around 30% of patients were managed with oxygen inhalation, 7% with noninvasive ventilation, and 3% required invasive ventilation. Whereas, in a study by Mohan et al., 3.5% of patients required oxygen supplementation, 2.8% patients had severe disease requiring intensive care, and one required invasive ventilation.[13] Sherwal et al. in their study noted that 10.7% required intensive care (without ventilator), 1.6% required ventilator, and only 0.3% required oxygen therapy alone.[16] In a study by Hasan et al., 5.3% of the study patients required ICU admission.[17]
In this study, ARDS, shock, and sepsis were seen in 1.5%. Other common complications listed in literature are acute cardiac injury, sepsis, multiorgan failure, renal failure, and death.[15],[16],[18] Mortality was 1.1% in this study comparable to 1.4% as per Mohan et al.[13]
Laboratory parameters among the study subjects
Laboratory parameters among the study subjects showed that 12.1% had leukocytosis, 4.5% leucopenia, 1.5% thrombocytopenia, 2.5% lymphocytosis, 1.5% lymphocytopenia, 17.2% elevated CRP levels, 1.1% elevated D-dimer levels, 1.1% prolonged prothrombin time, 0.5% elevated aspartate transaminase and aminotransferase each, 2.1% elevated ESR, and 1.1% elevated creatinine. According to the study findings of Bhandari et al., 52.38% had lymphopenia during the course of admission, 14.28% had leukocytosis, and 19.04% had thrombocytopenia. All patients in the severe category had raised fibrin degradation product, D-dimer levels along with deranged liver functions, and elevated procalcitonin levels, serum ferritin levels, and lactate dehydrogenase levels[19] According to Rousan et al., the most common finding on chest X-ray was peripheral ground-glass opacities affecting the lower lobes, which is comparable to our study.[20]
Association of various sociodemographic and clinicoepidemiological factors with severity of illness
Gurtoo et al. reported a mean age of 38.6 ± 15.4 years, 46.4 ± 14.6 years, and 53.5 ± 16.1 years among mild, moderate, and severe categories of COVID-19, respectively, which was statistically significant. Similarly, in our study, the mean age in patients with severe and critical disease was 43.33 ± 6.12 years, which was significantly higher when compared to the mean age of 35.19 ± 8.64 years in patients with mild and moderate disease. Although the mean age differed significantly, its association with severity was not significant in our study.[21] Similar to Gurtoo et al., gender was not significantly associated with the severity.[21] Gupta et al. in their retrospective study observed higher mortality both in previously treated TB cases and in coinfection of both.[22] However, in our study, there was no significant association found between history of TB in the past and this difference may be due to the difference in the time elapsed between the recovery from TB infection and the occurrence of this COVID-19 condition. Mohapatra et al. have quoted that the BCG vaccination in childhood may not have protective effect against COVID-19 in adulthood as the effect of BCG vaccination is moderate and lasts for nearly 20 years.[23] Gurtoo et al. have also found that associated comorbidities were higher in the nonsurvival group compared to survival group indirectly, indicating its association with the severe disease and its adverse outcome.[21] In our study, proportions of patients with severe disease or critical illness having blood group O was higher. This is contradictory to few studies wherein; blood group O was reported to have some protection against COVID-19 infection and mortality. However, a recent meta-analysis found no significant differences in severity outcomes in patients with different blood groups. In-depth studies in larger samples need to be conducted to evaluate the same.[24] Nagarajan et al. found midlower zone involvement and no exclusive upper zone involvement on X-ray and ground-glass opacification was the most common finding followed by peripheral lung opacities and confluent consolidation. However, pleural effusion was an uncommon finding and they concluded confluent consolidation to indicate more severe disease. Similarly, in our study, lower zone followed by midlower zone involvement, peripheral lung lesions were noted and associated pleural effusions were least noted.[25] CRP, ESR, and D-dimer are said to be potential biomarkers and are noted to be associated with the severity of COVID-19.[26] Rao et al. found that those patients with mild-to-moderate symptoms did not require supplemental oxygen and had an improved outcome similar to our study.[27]
The average duration of hospitalization was around 16 days in a study by Rao et al., similar to ours where we found it to be 14 days.[27] Rees et al. in their study documented that the estimates of length of stay in the hospital were shorter than those who were discharged alive. However, in our study, the length of stay was observed to be higher in severe/nonsurvivors compared to those who survived,[28] and this may be due to the difference in the hospital settings and other confounders factors such as comorbidities and age. The average time taken to become COVID negative by RT-PCR was 37.93 ± 7.54 days. According to Mohan et al. and Bhandari et al., the time for RT-PCR negativity was 16.9 ± 2.9 days and 8.8 ± 3.5 days.[7],[13] The WHO has cited that viral RNA to be detected in upper respiratory tract and lower respiratory tract and feces, irrespective of severity of disease and has quoted that there seems to be a trend in longer detection of viral RNA in more severely ill patients.[29] However, the duration to become COVID negative by RT-PCR did not vary significantly with the severity, and this may be due to the fact that RT-PCR test is said to detect virus even after it becomes inactive and noninfectious as per ICMR.[30]
Limitations of this study are inherent to its small sample size. Further studies with higher sample sizes are recommended to establish stronger association. Furthermore, patients could not be followed up to observe the sequelae of the disease.
To conclude, migrant population is not only at risk of contracting COVID but can also transmit the disease if not screened and isolated at the right time. This study conducted among the COVID-positive migrant population encompasses their clinicoepidemiological profile and outcomes. Middle-aged males were commonly affected and hypertension was the most common comorbidity. Majority of the patients had mild-to-moderate disease and developed fever. Respiratory support was given in one-third of cases and overall outcomes were satisfactory. A significant association with severity was observed in the presence of comorbidities, “O” blood group, abnormal X-ray findings, elevated levels of CRP, D-dimer, and ESR.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]
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