Some of the Covid-19 affected passengers recently screened at the Thiruvananthapuram and Delhi airports did not show any symptoms of the disease. The ineffectiveness of screening at airports is corroborated by a recent World Health Organisation (WHO) document, which says most recent data indicates 46 per cent of infected travellers would not be detected by airport screening.
"This suggests that unlike the 2009 H1N1 epidemic, which found that airport entry screening was associated with an average delay of 7-12 days in local transmission, for COVID-19, airport screening is unlikely to detect a sufficient proportion of infected travellers and prevent entry of infected travellers. Some countries have decided to raise the threshold for airport screening, to capture those with potentially less severe symptoms. This may have greater impact on disease transmission through air travel, but this requires further investigation to determine whether this makes a difference", said the WHO research and development Blue Print on research to prevent the disease.
As of today, total cases in India have risen to 125 with 3 deaths. Across the globe, the virus has so far killed more than 6,000 people and over 1.7 lakh are infected.
"The travel restrictions have had a more marked effect on an international scale, with modelling indicating that the number of case importations would be reduced by 80% by the end of February 2020. However, these modelling results also indicate that sustained 90% travel restrictions to and from mainland China only modestly affect the epidemic trajectory unless combined with a 50% or higher reduction of transmission in the community," said the document. On 11-12 February 2020, WHO, in collaboration with the Global Research Collaboration for Infectious Disease Preparedness and Response (GLOPID-R)-an international network of funders to facilitate coordination and information sharing, had organized a Global Forum on research and innovation for COVID-19 (Global Research Forum). The two day meeting, attended by over 400 experts from across the globe, was to formulate the Blueprint strategy as a framework.
The document said anecdotal feedback from clinicians on the ground in China reported a spectrum of disease, with no gender predilection. Many patients showed mild symptoms early-but progressed rapidly over a day. Also, there was evidence of prolonged prodrome, with interval of 7 to 10 days after hospitalisation before acute deterioration and requirement for ICU admission.