Indian Journal of Community and Family Medicine

: 2021  |  Volume : 7  |  Issue : 1  |  Page : 41--48

First few cases of COVID-19 admitted in a teaching hospital of North Kerala – Insights gained on the clinico-epidemiological presentations, management and patient perceptions on transmission dynamics

Asma Ayesha Rahim1, Sujina V Muthukutty1, Shinas P Babu2, Praseeda Chandran1, M P Shahul Hameed1, SP Anitha2,  
1 Department of Community Medicine, Government Medical College, Manjeri, Kerala, India
2 Department of Medicine, Government Medical College, Manjeri, Kerala, India

Correspondence Address:
Dr. Asma Ayesha Rahim
Department of Community Medicine, Government Medical College, Manjeri, Kerala


Introduction: The first case of COVID-19 in India was confirmed in Kerala on January 2020, with the state effectively crushing the epidemic curve. Objectives: This study aims to describe the clinico-epidemiological profile and transmission dynamics of confirmed COVID-19 cases admitted in our health care facility. Materials and Methods: A case series study of 19 laboratory-confirmed cases in the early pandemic phase was done (13th March–April 9th 2020). Information on sociodemographic variables, exposure histories, clinical symptoms, and treatment were collected from case records and in-depth telephonic interviews. Descriptive analysis of selected variables was done. Incubation periods and receipt of infection were estimated from patient histories. Results: About 78.9% were male, in the age group of 22–86 years (Median-42 years). 18/19 (94.7%) of laboratory-confirmed cases were imported, half of them from UAE. Fever and cough were the predominant symptoms, followed by sore throat, breathlessness, headache, muscle pain, and loose stools with majority (85%) reporting mild symptoms. Five patients were asymptomatic. Mean duration from symptom onset to reporting is 4 ± 4.47 days. Two patients developed complications, one requiring hemodialysis and ventilator support. About 42% of patients had at least one comorbidity. Mean duration of symptom clearance and hospital stay was 6.76 days and 19.41 ± 6.801 days, respectively. Virological clearance was noted in 13.06 ± 7.32 days. Conclusions: Epidemiological findings from these cases aided in prompt public health responses across the districts in Kerala.

How to cite this article:
Rahim AA, Muthukutty SV, Babu SP, Chandran P, Hameed M P, Anitha S P. First few cases of COVID-19 admitted in a teaching hospital of North Kerala – Insights gained on the clinico-epidemiological presentations, management and patient perceptions on transmission dynamics.Indian J Community Fam Med 2021;7:41-48

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Rahim AA, Muthukutty SV, Babu SP, Chandran P, Hameed M P, Anitha S P. First few cases of COVID-19 admitted in a teaching hospital of North Kerala – Insights gained on the clinico-epidemiological presentations, management and patient perceptions on transmission dynamics. Indian J Community Fam Med [serial online] 2021 [cited 2021 Sep 18 ];7:41-48
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The detection and spread of COVID-19 as a localized outbreak in China and later into pandemic proportions is accompanied by uncertainty over the key epidemiological, clinical, and virological characteristics of the novel pathogen and particularly its ability to spread in the human population and its virulence.[1]

The outbreak was identified in Wuhan, China, in December 2019.[2] The World Health Organization declared the outbreak to be a Public Health Emergency of International Concern on 30 January 2020, and recognized it as a pandemic on March 11, 2020.[3],[4] On January 30, 2020, a laboratory-confirmed case of 2019-nCoV was reported in Kerala in a student returning from Wuhan, followed by three cases between January 30, and February 3, 2020.

Our health care facility initiated screening and collecting samples for testing from February 12, 2020. On January 24, isolation facilities were set up in the hospital with 12 beds and facilities upscaled periodically based on national guidelines.[5],[6]

It is essential to understand the epidemiological, clinical, and virological characteristics of the First Few cases of COVID-19 to inform targeted guidance and measures for our districts public health response.[7] Few international and national studies have been published based on preliminary findings on epidemiology of COVID-19. To treat new infections and prevent further transmission, it is necessary to analyze and share epidemiological data of the cases reported from our setting. Our aim is to describe the epidemiology, transmission classification, transmission dynamics, and clinical presentation of first 19 cases admitted in the early phase of the pandemic.

 Materials and Methods

We did a case series study of all 19 laboratory-confirmed COVID-19 infections admitted at our health facility during the early pandemic phase. Relevant information of all cases from March 13, 2020 to April 9, 2020 were collected. Standard operational definitions of suspect case, confirmed case, asymptomatic transmission, recovered case, and incubation period were utilized for case inclusion and analysis.[8],[9],[10] The research was approved by the Institutional Ethics Review Committee.

Data collection

We elicited requisite information from two sources, secondary data from hospital records and personal in-depth telephonic interviews. Details of clinical symptoms, exposures, contact with confirmed case(s), and preexisting conditions were collected. Results of reverse transcription-polymerase chain reaction (RTPCR) from respiratory PCR Specimens were accessed from the hospital records. Epidemiological data were gathered from the risk assessment tool developed by our team in the COVID-19 triage zone. This data were cross checked with data in the case sheets for completeness.

In symptomatic patients, IP was calculated from time of exposure to onset of clinical symptoms. In asymptomatic patients Incubation period was modeled based on exposure histories. Time of possible exposures was ascertained from patients version as majority had a travel history. Secondary attack rates were calculated by constructing detailed route maps of the patients and identifying all primary and secondary contacts having exposed to the case from the date of arrival.


Of the 19 cases, 15 were men (78.9%) and 4 were women (21.1%). Cases ranged from 22 to 85 years with a median of 42 years (interquartile range [IQR] = 20), with 14 (73.6%) in 30–59 age category. Three patients were aged 60 and above. All cases belonged to the Muslim community. A spatial clustering of cases along the coastal belt of the district was noted on geographical mapping [Figure 1].{Figure 1}

18/19 (94.7%) of cases were imported fitting (now revised as “Cluster of cases”) into the transmission classification of the WHO.[10] One case fitted into the local transmission category. Case-P12 was a faith healer who had direct contact with his son who returned from Umra pilgrimage to Mecca on 11/3/20, who chose to remain in home quarantine without reporting the symptoms to the surveillance system. P12 is also reported to have had multiple contact with believers who had returned from abroad seeking spiritual help. Of the 18 cases, 12 were imported from abroad and 6 of them had a history of interstate travel [Table 1].{Table 1}

Purpose of travel

Nine of the imported cases had been residing in middle east. Two cases reported travel for Umra pilgrimage to the holy cities of Mecca and Medina and had transited through Jeddah. Six of them had participated in religious gatherings in Delhi and Mumbai in the month of February and March. One was a student from Edinburgh, Scotland. Locations in UAE were Hamdan street, Abudhabi, Deira Dubai, Naif, an Arabic souk in Dubai.


6/12 (50%) travellers reported symptoms before arrival. A similar proportion either continued to have symptoms or developed symptoms on arrival. About 90% had symptoms on the date of reporting to health facility. 9/12 (75%) reported symptoms during home quarantine/isolation in the hospital [Table 1]. [Table 1] denotes the location and number of cases based on symptom reporting and symptom onset.

Initial symptoms reported by patients are fever (11 patients, 57.89%), sore throat (n = 4 patients, 21%), cough or sputum production (6 patients, 31.57%), breathlessness (2 patients, 10.5%), and muscle ache (1 patient, 5.2%).5 (26.3%) patients reported no symptoms falling into the asymptomatic category.

14 cases (73.7%) experienced symptoms on reporting to hospital. The recorded symptoms on admission were fever, sore throat, cough, breathlessness and headache, and muscle pain and loose stools as depicted in [Table 2]. Mean duration from symptom onset to reporting to health facility among symptomatic is calculated as 4 ± 4.47 days (median-2.5 days).{Table 2}

Clinical (P2 and P12) and radiologic evidence of pneumonia were noted in 3 patients. 1 patient(P15) was asymptomatic but Chest X-ray showed right lower lobe alveolar shadow.

12/14 (85.7%) patients exhibited mild symptoms, with two cases progressing to complications. P12 turned critical requiring hemodialysis and ventilator support.

Based on revised guidelines (24/3/20) by ICMR, screening of cases and categorization of all cases at the time of admission was done in the COVID-19 outpatient department.[11]

[Figure 2] illustrates the time line of first throat swab and blood sample collection for confirmation.{Figure 2}

A steady influx of confirmed cases is illustrated in [Figure 2]. The interval between hospital admission and RTPCR positivity (based on first sample) ranged from 1 to 7 days (Median-2 days). Interval between collection of first- and second-negative sample ranged from 2 to 3 days.

Mean duration of being symptomatic is 6.76 days (Median-4 days, IQR = 1–26 days) from the date of contact with health facility [Figure 3]. The mean duration of hospital stay following virological clearance was 19.41 ± 6.801 days (median-20 days) based on two consecutive negative throat swabs in an interval of 24 h.{Figure 3}


About 42% of patients (8/19) had at least one comorbidity [Table 2]. P2 reported COPD and P12 had diabetes, hypertension, and previous history of CAD.

TREATMENT DETAILS: All patients were administered oseltamivir and hydroxychloroquine following the interim treatment guidelines.[11] 12/19 received azithromycin, with two in this group receiving moxclav and piptaz in addition. Lopinavir and ritonavir was started on compassionate grounds with state medical board approval on two patients with critical presentations. Rapid X-ray clearance and symptomatic improvement was noted within a day into treatment on lopinavir and ritonavir.

However, Case P12, developed acute coronary syndrome followed by acute kidney injury, sepsis, and multi organ failure and died after 18 days of admission and 9 days after virological clearance.

Symptom clearance and virological clearance

We calculated transmission dynamics of the disease based on actual date of symptom onset fitting into case definition of COVID-19 from patient version. Based on this, the minimum and maximum IP estimated [Figure 3].

Events such as clinical recovery and virological clearance can be interpreted from the graph. X axis “0” denotes the day of reporting to health facility [Figure 3]. Virological clearance from the date of reporting is noted to be 13.06 ± 7.32 days (median-13 days).

Lab parameters

Liver function test and renal function test (RFT) were noted to be within normal limits for all the patients at admission. P12 showed derangement of RFT on day 13 of admission. Chest X-rays were evaluated for opacities indicative of pneumonia. Neutrophil to lymphocyte count was estimated in17 out of 19 patients. 5 out of 17 patients (26.3%) had a high N/L ratio of 3.5 and above. In both patients who had a severe presentation N/L ratio was high.

Secondary infection rate (SIR) and secondary clinical attack rate

The total number of primary and secondary contacts for the 19 confirmed cases traced out by District health administration was 1743 and 5211, respectively. Around 8% of contacts on home quarantine reported symptoms. All the close primary contacts were tested. None of them reported positivity.


The median age group of patients (42.6 years) is similar to the Delhi and South Korean study.[12],[13] Relative higher age groups were reported from China and in WHO report.[14],[15],[16],[17]

Male preponderance was (78.9%) similar to the Delhi figures (66.7%), concordant with studies from China and Korea. The sex ratio among the confirmed cases globally reported is 1.03:1 (WHO).[12],[13],[17]

All cases belonged to the Muslim community, which is the predominant religion in the district (70.24%).[18] A spatial clustering may be due to sharing common exposures such as engaged in job overseas and religious gatherings [Figure 1].

Transmission in the countries based on the WHO situation report

About 50% of cases were from UAE, corroborating with the fact that UAE had started to report with 4 cases from late February reporting local transmission. Almost 70% of the active cases at the moment in Kerala have links to Naif, a large commercial market in Dubai, where the laborers are cramped into one room. Two cases returning from Saudi Arabia might have contracted infections during pilgrimage from hot spot countries in February, especially Iran.[19]

By the 16th of March, 171 cases had been confirmed in Scotland from 4895 tests[20] These findings of the initial clusters relating to import of cases is similar in many countries, points to the ability of this virus to spread far and wide in a short span of time.

All 12 cases had been screened at the airport, those reporting symptoms were directly transferred to health facility for swab collection followed by admission, and the rest were placed under home quarantine. Through a strong decentralized system of daily case reporting and surveillance symptoms were ascertained by twice daily telephonic enquiry and suspects were transported to the facility in designated ambulance available in the toll free number, through DISHA, the 24-h tele-health helpline.[21] A team of trained students and faculty from our institution actively participated in disseminating specific health awareness messages for asymptomatic travelers send for home quarantine.

Six cases related to Interstate travel reported participating in gathering of a particular religious sect in Delhi and Mumbai. All of them had multiple interactions with believers at various points of the journey.[22]

Fever as the initial and most associated symptom as noted in our setting is consistent with the findings from multiple studies. Substantiating the observations evolving globally, 86% of cases had mild symptoms and all of them responded to conservative management.[14],[15],[16],[23] Unlike the Chinese and Korean study, Chills were not reported in our cases as in the Delhi study.[14]

Multiple studies have documented age as a significant risk factor for complications and mortality as evidenced by the complications reported among 2 elderly patients in this study too.[16],[24],[25]

About 26.3% of cases fell into the asymptomatic category and this cluster was noted among pilgrims with interstate travel. Studies from Diamond Princess cruise ship, New York city and China's National Health Commission reports asymptomatic infection as 51·7%, 87.9%, and 78%, respectively.[26],[27],[28],[29] Moreover, transmission before the onset of symptoms has been reported.[30],[31],[32]

The mean duration of being symptomatic was 9.3 days (2–34 days) and median duration, 5 days from the date of hospital admission based on patient version in our study, similar to a Chinese observation.[33],[34] Mean duration of hospital stay was 19.41 ± 6.801 for the cases, akin to the finding from a Beijing hospital.[35]

Though we had 2 cases on lopinavir and ritonavir exhibiting rapid clinical improvement, these are individual case reports and needs to be viewed with caution, considering the susceptibility to bias for observational studies.[36] There are some preliminary evidence of the effectiveness of lopinavir/ritonavir against other coronaviruses.[37],[38] However, a recent randomized trial has not found any benefit over time from the use of these drugs.[39] Chloroquine has also been evaluated in individual studies and may have a role in the management of COVID-19 in times to come.[40]

Virological clearance in this study is similar to reports from China.[40] Data from clinical and virologic studies that have collected repeated biological samples from confirmed patients provide evidence that shedding of the COVID-19 virus is highest in upper respiratory tract (nose and throat) early in the course of the disease and may be more contagious.[40],[41],[42] This may be the reason for low transmissibility of infection among the primary contacts in our study. However, few cases have been reported in which patients infected their close contacts even after “apparent recovery” from the infection.[30],[43],[44]

Most importantly, experts claim that RT-PCR positivity is not be synonymous with infectivity. The possible reasons argued by a large number of experts are related to several virological, immunological, and sampling methodological factors. Virologically, the false negatives, viral residual, intermittent viral release, and viral distribution are usually considered to be major factors.[45],[46],[47] RT-PCR is positive when viral RNA sequences tested are present in the sample and can be amplified and thus detected. This can happen several weeks after the disease onset and many days after the patient has become asymptomatic. Usually, in such cases, the viral RNA copy numbers are low. Such cases do not represent the infective stage. Infectivity of a sample is indicated by the ability to culture the virus from it. Alternatively, RT-PCR for subgenomic mRNA can detect cells in the active replicating phase and so presumably infective.[48]

In this preliminary study, we tried to gain early understanding of key clinical, epidemiological, and virological characteristics of the first cases of COVID-19 infection detected in Malappuram district of Kerala state. This investigation helped to compare and contrast the findings from the cases admitted in our settings to the rapid and superfluous information evolving from several countries globally.

Results highlight the imported nature of the early pandemic in Kerala and India. We emphasize stringent screening, testing, isolation, and institutional quarantine of international and interstate travelers during postlockdown in Kerala. Testing for asymptomatics from high risk zones should be done on the 5th and 14th days, prior to release from quarantine to halt local spread.

Kerala state has reported persistent RTPCR positivity for symptomatic and asymptomatic travellers on sentinel surveillance drive. Considering the available research evidence and the findings from our study, we consider RTPCR positivity not to be synonymous with infectivity. This may serve to create panic in the community and place heavy burden on the limited resources, which may be diverted to improve the surge capacity of health care institutions as well as testing, contact tracing and quarantine.

As there was no community transmission during the study of these cases. Hence, we presume that the decentralized model of early COVID-19 containment has been successful in Kerala and may be emulated in the national context.


This case series of 19 laboratory-confirmed cases in the early pandemic phase helped us understand the epidemiological, clinical, and virological characteristics of a novel pathogen at a time when scarce regional data were available. Findings were disseminated across targeted guidance to aid treatment and districts public health response. The findings added value in treating new infections and preventing further transmission. We emphasized stringent screening, testing, isolation, and institutional quarantine of international and interstate travelers during postlockdown in the district and highlighted the imported nature of the early pandemic in Kerala. Our conclusion is that decentralized model of early COVID-19 containment in the first phase of the Pandemic in Kerala is successful and may be emulated in the national context.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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