Unknowns exceed the knowns: Even today, experts admit, unknowns about the virus exceed the knowns. Further, they say, that uncertainties about the efficacy of vaccines still loom large over the medical fraternity. They say that combatting the pandemic will be possible when a complete understanding of the virus, including its epidemiological and clinical dimensions are arrived at. Till date the duration of immunity persistence against Covid-19 remains unknown. It has been assumed so far that vaccines are the way ahead in battling the virus. However, this assumption can be tested only a few months after the vaccine has been used on different populations. Further, they note the fact that the pandemic has hampered the progress towards Millennium Development Goals which aimed at halting the spread of other diseases such as HIV/AIDs and Tuberculosis.
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