ABSTRACT
BACKGROUND Symptoms of Covid-19 are known to be non-specific ranging from asymptomatic cases to severe illness affecting multiple organ systems. The duration of viral RNA positivity and transmission varies in individuals. We describe the association between symptom characteristics and comorbid conditions with viral RNA positivity of SARSCoV-2 affected individuals. METHODS We conducted a record-based retrospective cohort study of 179 patients found to be positive for Covid-19 in Kasaragod district in Kerala. We included details of all patients found positive during the initial phases of the pandemic and recorded details regarding symptoms, duration of viral RNA positivity and the occurrence of transmission. The data were analysed using SPSS. RESULTS Any symptom was present in 68%. Fever (43%) was the most common symptom while 50% had at least one respiratory symptom. Increased duration of viral RNA positivity was found to be associated with presence of comorbid conditions. The majority of individuals who transmitted disease (75%) had some symptom, predominantly a respiratory symptom. CONCLUSION Respiratory symptoms are seen in half of the patients and viral RNA positivity was for a longer duration in patients with comorbid conditions.
ABSTRACT
An unprecedented outbreak of dengue occurred during 2017 in Kerala. Thiruvananthapuram was worst affected. We carried out a joint investigation with the Health department of the State, to understand the epidemiological and entomological factors involved in this outbreak, so as to develop strategies to contain it. Blood samples from suspected patients were collected from three worst affected areas and genomic analysis of the Dengue virus (DENV) was performed. Also, a cross sectional entomological survey was carried out in these areas. The data obtained was compared with the available secondary data of DENV in Kerala. The investigations revealed a genetic shift from the erstwhile predominant DENV2/DENV3 serotypes to the newly introduced DENV1 Asian genotype during the current outbreak. Breeding indices of Aedes aegypti, the predominant vector species was also found to be remarkably high. Asian genotype of DENV1 was detected in field collected Ae. aegypti also. The index cases of the Asian genotype of DENV1 in Kerala were detected from Erumeli village (gateway to the famous Sabarimala shrine) among two plantation workers migrated from the neighbouring Karnataka state, during 2013. This introduced virus strain attained an epidemic proportion in 2017 in Thiruvananthapuram, owing to immunologically naïve population and high receptivity.